Question: When would you use Operator pattern?

Answer: Operator patternOperators are software extensions to Kubernetes that make use of custom resources to manage applications and their components. Operators follow Kubernetes principles, notably the control loop.MotivationThe operator pattern aims to capture the key aim of a human operator who is managing a service or set of services. Human operators who look after specific applications and services have deep knowledge of how the system ought to behave, how to deploy it, and how to react if there are problems.People who run workloads on Kubernetes often like to use automation to take care of repeatable tasks. The operator pattern captures how you can write code to automate a task beyond what Kubernetes itself provides.Operators in KubernetesKubernetes is designed for automation. Out of the box, you get lots of built-in automation from the core of Kubernetes. You can use Kubernetes to automate deploying and running workloads, and you can automate how Kubernetes does that.Kubernetes' operator pattern concept lets you extend the cluster's behaviour without modifying the code of Kubernetes itself by linking controllers to one or more custom resources. Operators are clients of the Kubernetes API that act as controllers for a Custom Resource.An example operatorSome of the things that you can use an operator to automate include:deploying an application on demandtaking and restoring backups of that application's statehandling upgrades of the application code alongside related changes such as database schemas or extra configuration settingspublishing a Service to applications that don't support Kubernetes APIs to discover themsimulating failure in all or part of your cluster to test its resiliencechoosing a leader for a distributed application without an internal member election processWhat might an operator look like in more detail? Here's an example:A custom resource named SampleDB, that you can configure into the cluster.A Deployment that makes sure a Pod is running that contains the controller part of the operator.A container image of the operator code.Controller code that queries the control plane to find out what SampleDB resources are configured.The core of the operator is code to tell the API server how to make reality match the configured resources.If you add a new SampleDB, the operator sets up PersistentVolumeClaims to provide durable database storage, a StatefulSet to run SampleDB and a Job to handle initial configuration.If you delete it, the operator takes a snapshot, then makes sure that the StatefulSet and Volumes are also removed.The operator also manages regular database backups. For each SampleDB resource, the operator determines when to create a Pod that can connect to the database and take backups. These Pods would rely on a ConfigMap and / or a Secret that has database connection details and credentials.Because the operator aims to provide robust automation for the resource it manages, there would be additional supporting code. For this


Question: What are the benefits of Operator pattern?

Answer: Operator patternOperators are software extensions to Kubernetes that make use of custom resources to manage applications and their components. Operators follow Kubernetes principles, notably the control loop.MotivationThe operator pattern aims to capture the key aim of a human operator who is managing a service or set of services. Human operators who look after specific applications and services have deep knowledge of how the system ought to behave, how to deploy it, and how to react if there are problems.People who run workloads on Kubernetes often like to use automation to take care of repeatable tasks. The operator pattern captures how you can write code to automate a task beyond what Kubernetes itself provides.Operators in KubernetesKubernetes is designed for automation. Out of the box, you get lots of built-in automation from the core of Kubernetes. You can use Kubernetes to automate deploying and running workloads, and you can automate how Kubernetes does that.Kubernetes' operator pattern concept lets you extend the cluster's behaviour without modifying the code of Kubernetes itself by linking controllers to one or more custom resources. Operators are clients of the Kubernetes API that act as controllers for a Custom Resource.An example operatorSome of the things that you can use an operator to automate include:deploying an application on demandtaking and restoring backups of that application's statehandling upgrades of the application code alongside related changes such as database schemas or extra configuration settingspublishing a Service to applications that don't support Kubernetes APIs to discover themsimulating failure in all or part of your cluster to test its resiliencechoosing a leader for a distributed application without an internal member election processWhat might an operator look like in more detail? Here's an example:A custom resource named SampleDB, that you can configure into the cluster.A Deployment that makes sure a Pod is running that contains the controller part of the operator.A container image of the operator code.Controller code that queries the control plane to find out what SampleDB resources are configured.The core of the operator is code to tell the API server how to make reality match the configured resources.If you add a new SampleDB, the operator sets up PersistentVolumeClaims to provide durable database storage, a StatefulSet to run SampleDB and a Job to handle initial configuration.If you delete it, the operator takes a snapshot, then makes sure that the StatefulSet and Volumes are also removed.The operator also manages regular database backups. For each SampleDB resource, the operator determines when to create a Pod that can connect to the database and take backups. These Pods would rely on a ConfigMap and / or a Secret that has database connection details and credentials.Because the operator aims to provide robust automation for the resource it manages, there would be additional supporting code. For this


Question: What is Operator pattern?

Answer: O p e r a t o r s   a r e   s o f t w a r e   e x t e n s i o n s   t o   K u b e r n e t e s   t h a t   m a k e   u s e   o f   c u s t o m   r e s o u r c e s   t o   m a n a g e   a p p l i c a t i o n s   a n d   t h e i r   c o m p o n e n t s .   O p e r a t o r s   f o l l o w   K u b e r n e t e s   p r i n c i p l e s ,   n o t a b l y   t h e   c o n t r o l   l o o p .


Question: What is Motivation?

Answer: T h e   o p e r a t o r   p a t t e r n   a i m s   t o   c a p t u r e   t h e   k e y   a i m   o f   a   h u m a n   o p e r a t o r   w h o   i s   m a n a g i n g   a   s e r v i c e   o r   s e t   o f   s e r v i c e s .   H u m a n   o p e r a t o r s   w h o   l o o k   a f t e r   s p e c i f i c   a p p l i c a t i o n s   a n d   s e r v i c e s   h a v e   d e e p   k n o w l e d g e   o f   h o w   t h e   s y s t e m   o u g h t   t o   b e h a v e ,   h o w   t o   d e p l o y   i t ,   a n d   h o w   t o   r e a c t   i f   t h e r e   a r e   p r o b l e m s .   P e o p l e   w h o   r u n   w o r k l o a d s   o n   K u b e r n e t e s   o f t e n   l i k e   t o   u s e   a u t o m a t i o n   t o   t a k e   c a r e   o f   r e p e a t a b l e   t a s k s .   T h e   o p e r a t o r   p a t t e r n   c a p t u r e s   h o w   y o u   c a n   w r i t e   c o d e   t o   a u t o m a t e   a   t a s k   b e y o n d   w h a t   K u b e r n e t e s   i t s e l f   p r o v i d e s .


Question: What is Operators in Kubernetes?

Answer: K u b e r n e t e s   i s   d e s i g n e d   f o r   a u t o m a t i o n .   O u t   o f   t h e   b o x ,   y o u   g e t   l o t s   o f   b u i l t - i n   a u t o m a t i o n   f r o m   t h e   c o r e   o f   K u b e r n e t e s .   Y o u   c a n   u s e   K u b e r n e t e s   t o   a u t o m a t e   d e p l o y i n g   a n d   r u n n i n g   w o r k l o a d s ,   a n d   y o u   c a n   a u t o m a t e   h o w   K u b e r n e t e s   d o e s   t h a t .   K u b e r n e t e s '   o p e r a t o r   p a t t e r n   c o n c e p t   l e t s   y o u   e x t e n d   t h e   c l u s t e r ' s   b e h a v i o u r   w i t h o u t   m o d i f y i n g   t h e   c o d e   o f   K u b e r n e t e s   i t s e l f   b y   l i n k i n g   c o n t r o l l e r s   t o   o n e   o r   m o r e   c u s t o m   r e s o u r c e s .   O p e r a t o r s   a r e   c l i e n t s   o f   t h e   K u b e r n e t e s   A P I   t h a t   a c t   a s   c o n t r o l l e r s   f o r   a   C u s t o m   R e s o u r c e .


Question: What is An example operator?

Answer: S o m e   o f   t h e   t h i n g s   t h a t   y o u   c a n   u s e   a n   o p e r a t o r   t o   a u t o m a t e   i n c l u d e :   d e p l o y i n g   a n   a p p l i c a t i o n   o n   d e m a n d t a k i n g   a n d   r e s t o r i n g   b a c k u p s   o f   t h a t   a p p l i c a t i o n ' s   s t a t e h a n d l i n g   u p g r a d e s   o f   t h e   a p p l i c a t i o n   c o d e   a l o n g s i d e   r e l a t e d   c h a n g e s   s u c h   a s   d a t a b a s e   s c h e m a s   o r   e x t r a   c o n f i g u r a t i o n   s e t t i n g s p u b l i s h i n g   a   S e r v i c e   t o   a p p l i c a t i o n s   t h a t   d o n ' t   s u p p o r t   K u b e r n e t e s   A P I s   t o   d i s c o v e r   t h e m s i m u l a t i n g   f a i l u r e   i n   a l l   o r   p a r t   o f   y o u r   c l u s t e r   t o   t e s t   i t s   r e s i l i e n c e c h o o s i n g   a   l e a d e r   f o r   a   d i s t r i b u t e d   a p p l i c a t i o n   w i t h o u t   a n   i n t e r n a l   m e m b e r   e l e c t i o n   p r o c e s s   W h a t   m i g h t   a n   o p e r a t o r   l o o k   l i k e   i n   m o r e   d e t a i l ?   H e r e ' s   a n   e x a m p l e :   A   c u s t o m   r e s o u r c e   n a m e d   S a m p l e D B ,   t h a t   y o u   c a n   c o n f i g u r e   i n t o   t h e   c l u s t e r . A   D e p l o y m e n t   t h a t   m a k e s   s u r e   a   P o d   i s   r u n n i n g   t h a t   c o n t a i n s   t h e   c o n t r o l l e r   p a r t   o f   t h e   o p e r a t o r . A   c o n t a i n e r   i m a g e   o f   t h e   o p e r a t o r   c o d e . C o n t r o l l e r   c o d e   t h a t   q u e r i e s   t h e   c o n t r o l   p l a n e   t o   f i n d   o u t   w h a t   S a m p l e D B   r e s o u r c e s   a r e   c o n f i g u r e d . T h e   c o r e   o f   t h e   o p e r a t o r   i s   c o d e   t o   t e l l   t h e   A P I   s e r v e r   h o w   t o   m a k e   r e a l i t y   m a t c h   t h e   c o n f


Question: What is Deploying operators?

Answer: T h e   m o s t   c o m m o n   w a y   t o   d e p l o y   a n   o p e r a t o r   i s   t o   a d d   t h e   C u s t o m   R e s o u r c e   D e f i n i t i o n   a n d   i t s   a s s o c i a t e d   C o n t r o l l e r   t o   y o u r   c l u s t e r .   T h e   C o n t r o l l e r   w i l l   n o r m a l l y   r u n   o u t s i d e   o f   t h e   c o n t r o l   p l a n e ,   m u c h   a s   y o u   w o u l d   r u n   a n y   c o n t a i n e r i z e d   a p p l i c a t i o n .   F o r   e x a m p l e ,   y o u   c a n   r u n   t h e   c o n t r o l l e r   i n   y o u r   c l u s t e r   a s   a   D e p l o y m e n t .


Question: What is Using an operator?

Answer: O n c e   y o u   h a v e   a n   o p e r a t o r   d e p l o y e d ,   y o u ' d   u s e   i t   b y   a d d i n g ,   m o d i f y i n g   o r   d e l e t i n g   t h e   k i n d   o f   r e s o u r c e   t h a t   t h e   o p e r a t o r   u s e s .   F o l l o w i n g   t h e   a b o v e   e x a m p l e ,   y o u   w o u l d   s e t   u p   a   D e p l o y m e n t   f o r   t h e   o p e r a t o r   i t s e l f ,   a n d   t h e n :   k u b e c t l   g e t   S a m p l e D B   #   f i n d   c o n f i g u r e d   d a t a b a s e s   k u b e c t l   e d i t   S a m p l e D B / e x a m p l e - d a t a b a s e   #   m a n u a l l y   c h a n g e   s o m e   s e t t i n g s   … a n d   t h a t ' s   i t !   T h e   o p e r a t o r   w i l l   t a k e   c a r e   o f   a p p l y i n g   t h e   c h a n g e s   a s   w e l l   a s   k e e p i n g   t h e   e x i s t i n g   s e r v i c e   i n   g o o d   s h a p e .


Question: What is Writing your own operator?

Answer: I f   t h e r e   i s n ' t   a n   o p e r a t o r   i n   t h e   e c o s y s t e m   t h a t   i m p l e m e n t s   t h e   b e h a v i o r   y o u   w a n t ,   y o u   c a n   c o d e   y o u r   o w n .   Y o u   a l s o   i m p l e m e n t   a n   o p e r a t o r   ( t h a t   i s ,   a   C o n t r o l l e r )   u s i n g   a n y   l a n g u a g e   /   r u n t i m e   t h a t   c a n   a c t   a s   a   c l i e n t   f o r   t h e   K u b e r n e t e s   A P I .   F o l l o w i n g   a r e   a   f e w   l i b r a r i e s   a n d   t o o l s   y o u   c a n   u s e   t o   w r i t e   y o u r   o w n   c l o u d   n a t i v e   o p e r a t o r .   C h a r m e d   O p e r a t o r   F r a m e w o r k J a v a   O p e r a t o r   S D K K o p f   ( K u b e r n e t e s   O p e r a t o r   P y t h o n i c   F r a m e w o r k ) k u b e - r s   ( R u s t ) k u b e b u i l d e r K u b e O p s   ( . N E T   o p e r a t o r   S D K ) M a s t M e t a c o n t r o l l e r   a l o n g   w i t h   W e b H o o k s   t h a t   y o u   i m p l e m e n t   y o u r s e l f O p e r a t o r   F r a m e w o r k s h e l l - o p e r a t o r


Question: What is What's next?

Answer: R e a d   t h e   C N C F   O p e r a t o r   W h i t e   P a p e r . L e a r n   m o r e   a b o u t   C u s t o m   R e s o u r c e s F i n d   r e a d y - m a d e   o p e r a t o r s   o n   O p e r a t o r H u b . i o   t o   s u i t   y o u r   u s e   c a s e P u b l i s h   y o u r   o p e r a t o r   f o r   o t h e r   p e o p l e   t o   u s e R e a d   C o r e O S '   o r i g i n a l   a r t i c l e   t h a t   i n t r o d u c e d   t h e   o p e r a t o r   p a t t e r n   ( t h i s   i s   a n   a r c h i v e d   v e r s i o n   o f   t h e   o r i g i n a l   a r t i c l e ) . R e a d   a n   a r t i c l e   f r o m   G o o g l e   C l o u d   a b o u t   b e s t   p r a c t i c e s   f o r   b u i l d i n g   o p e r a t o r s   I t e m s   o n   t h i s   p a g e   r e f e r   t o   t h i r d   p a r t y   p r o d u c t s   o r   p r o j e c t s   t h a t   p r o v i d e   f u n c t i o n a l i t y   r e q u i r e d   b y   K u b e r n e t e s .   T h e   K u b e r n e t e s   p r o j e c t   a u t h o r s   a r e n ' t   r e s p o n s i b l e   f o r   t h o s e   t h i r d - p a r t y   p r o d u c t s   o r   p r o j e c t s .   S e e   t h e   C N C F   w e b s i t e   g u i d e l i n e s   f o r   m o r e   d e t a i l s .   Y o u   s h o u l d   r e a d   t h e   c o n t e n t   g u i d e   b e f o r e   p r o p o s i n g   a   c h a n g e   t h a t   a d d s   a n   e x t r a   t h i r d - p a r t y   l i n k .


Question: What is Configure a Security Context for a Pod or Container?

Answer: Configure a Security Context for a Pod or ContainerA security context defines privilege and access control settings for a Pod or Container. Security context settings include, but are not limited to:Discretionary Access Control: Permission to access an object, like a file, is based on user ID (UID) and group ID (GID).Security Enhanced Linux (SELinux): Objects are assigned security labels.Running as privileged or unprivileged.Linux Capabilities: Give a process some privileges, but not all the privileges of the root user.AppArmor: Use program profiles to restrict the capabilities of individual programs.Seccomp: Filter a process's system calls.allowPrivilegeEscalation: Controls whether a process can gain more privileges than its parent process. This bool directly controls whether the no_new_privs flag gets set on the container process. allowPrivilegeEscalation is always true when the container:is run as privileged, orhas CAP_SYS_ADMINreadOnlyRootFilesystem: Mounts the container's root filesystem as read-only.The above bullets are not a complete set of security context settings -- please see SecurityContext for a comprehensive list.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesTo check the version, enter kubectl version.Set the security context for a PodTo specify security settings for a Pod, include the securityContext field in the Pod specification. The securityContext field is a PodSecurityContext object. The security settings that you specify for a Pod apply to all Containers in the Pod. Here is a configuration file for a Pod that has a securityContext and an emptyDir volume:pods/security/security-context.yaml apiVersion: v1 kind: Pod metadata: name: security-context-demo spec: securityContext: runAsUser: 1000 runAsGroup: 3000 fsGroup: 2000 supplementalGroups: [4000] volumes: - name: sec-ctx-vol emptyDir: {} containers: - name: sec-ctx-demo image: busybox:1.28 command: [ "sh", "-c", "sleep 1h" ] volumeMounts: - name: sec-ctx-vol mountPath: /data/demo securityContext: allowPrivilegeEscalation: false In the configuration file, the runAsUser field specifies that for any Containers in the Pod, all processes run with user ID 1000. The runAsGroup field specifies the primary group ID of 3000 for all processes within any containers of the Pod. If this field is omitted, the primary group ID of the containers will be root(0). Any files created will also be owned by user 1000 and group 3000 when runAsGroup is specified. Since fsGroup field is specified, all processes of the container are also part of the supplementary group ID 2000. The owner for volume /data/demo and any


Question: How does Configure a Security Context for a Pod or Container work?

Answer: Configure a Security Context for a Pod or ContainerA security context defines privilege and access control settings for a Pod or Container. Security context settings include, but are not limited to:Discretionary Access Control: Permission to access an object, like a file, is based on user ID (UID) and group ID (GID).Security Enhanced Linux (SELinux): Objects are assigned security labels.Running as privileged or unprivileged.Linux Capabilities: Give a process some privileges, but not all the privileges of the root user.AppArmor: Use program profiles to restrict the capabilities of individual programs.Seccomp: Filter a process's system calls.allowPrivilegeEscalation: Controls whether a process can gain more privileges than its parent process. This bool directly controls whether the no_new_privs flag gets set on the container process. allowPrivilegeEscalation is always true when the container:is run as privileged, orhas CAP_SYS_ADMINreadOnlyRootFilesystem: Mounts the container's root filesystem as read-only.The above bullets are not a complete set of security context settings -- please see SecurityContext for a comprehensive list.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesTo check the version, enter kubectl version.Set the security context for a PodTo specify security settings for a Pod, include the securityContext field in the Pod specification. The securityContext field is a PodSecurityContext object. The security settings that you specify for a Pod apply to all Containers in the Pod. Here is a configuration file for a Pod that has a securityContext and an emptyDir volume:pods/security/security-context.yaml apiVersion: v1 kind: Pod metadata: name: security-context-demo spec: securityContext: runAsUser: 1000 runAsGroup: 3000 fsGroup: 2000 supplementalGroups: [4000] volumes: - name: sec-ctx-vol emptyDir: {} containers: - name: sec-ctx-demo image: busybox:1.28 command: [ "sh", "-c", "sleep 1h" ] volumeMounts: - name: sec-ctx-vol mountPath: /data/demo securityContext: allowPrivilegeEscalation: false In the configuration file, the runAsUser field specifies that for any Containers in the Pod, all processes run with user ID 1000. The runAsGroup field specifies the primary group ID of 3000 for all processes within any containers of the Pod. If this field is omitted, the primary group ID of the containers will be root(0). Any files created will also be owned by user 1000 and group 3000 when runAsGroup is specified. Since fsGroup field is specified, all processes of the container are also part of the supplementary group ID 2000. The owner for volume /data/demo and any


Question: When would you use Configure a Security Context for a Pod or Container?

Answer: Configure a Security Context for a Pod or ContainerA security context defines privilege and access control settings for a Pod or Container. Security context settings include, but are not limited to:Discretionary Access Control: Permission to access an object, like a file, is based on user ID (UID) and group ID (GID).Security Enhanced Linux (SELinux): Objects are assigned security labels.Running as privileged or unprivileged.Linux Capabilities: Give a process some privileges, but not all the privileges of the root user.AppArmor: Use program profiles to restrict the capabilities of individual programs.Seccomp: Filter a process's system calls.allowPrivilegeEscalation: Controls whether a process can gain more privileges than its parent process. This bool directly controls whether the no_new_privs flag gets set on the container process. allowPrivilegeEscalation is always true when the container:is run as privileged, orhas CAP_SYS_ADMINreadOnlyRootFilesystem: Mounts the container's root filesystem as read-only.The above bullets are not a complete set of security context settings -- please see SecurityContext for a comprehensive list.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesTo check the version, enter kubectl version.Set the security context for a PodTo specify security settings for a Pod, include the securityContext field in the Pod specification. The securityContext field is a PodSecurityContext object. The security settings that you specify for a Pod apply to all Containers in the Pod. Here is a configuration file for a Pod that has a securityContext and an emptyDir volume:pods/security/security-context.yaml apiVersion: v1 kind: Pod metadata: name: security-context-demo spec: securityContext: runAsUser: 1000 runAsGroup: 3000 fsGroup: 2000 supplementalGroups: [4000] volumes: - name: sec-ctx-vol emptyDir: {} containers: - name: sec-ctx-demo image: busybox:1.28 command: [ "sh", "-c", "sleep 1h" ] volumeMounts: - name: sec-ctx-vol mountPath: /data/demo securityContext: allowPrivilegeEscalation: false In the configuration file, the runAsUser field specifies that for any Containers in the Pod, all processes run with user ID 1000. The runAsGroup field specifies the primary group ID of 3000 for all processes within any containers of the Pod. If this field is omitted, the primary group ID of the containers will be root(0). Any files created will also be owned by user 1000 and group 3000 when runAsGroup is specified. Since fsGroup field is specified, all processes of the container are also part of the supplementary group ID 2000. The owner for volume /data/demo and any


Question: What are the benefits of Configure a Security Context for a Pod or Container?

Answer: Configure a Security Context for a Pod or ContainerA security context defines privilege and access control settings for a Pod or Container. Security context settings include, but are not limited to:Discretionary Access Control: Permission to access an object, like a file, is based on user ID (UID) and group ID (GID).Security Enhanced Linux (SELinux): Objects are assigned security labels.Running as privileged or unprivileged.Linux Capabilities: Give a process some privileges, but not all the privileges of the root user.AppArmor: Use program profiles to restrict the capabilities of individual programs.Seccomp: Filter a process's system calls.allowPrivilegeEscalation: Controls whether a process can gain more privileges than its parent process. This bool directly controls whether the no_new_privs flag gets set on the container process. allowPrivilegeEscalation is always true when the container:is run as privileged, orhas CAP_SYS_ADMINreadOnlyRootFilesystem: Mounts the container's root filesystem as read-only.The above bullets are not a complete set of security context settings -- please see SecurityContext for a comprehensive list.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesTo check the version, enter kubectl version.Set the security context for a PodTo specify security settings for a Pod, include the securityContext field in the Pod specification. The securityContext field is a PodSecurityContext object. The security settings that you specify for a Pod apply to all Containers in the Pod. Here is a configuration file for a Pod that has a securityContext and an emptyDir volume:pods/security/security-context.yaml apiVersion: v1 kind: Pod metadata: name: security-context-demo spec: securityContext: runAsUser: 1000 runAsGroup: 3000 fsGroup: 2000 supplementalGroups: [4000] volumes: - name: sec-ctx-vol emptyDir: {} containers: - name: sec-ctx-demo image: busybox:1.28 command: [ "sh", "-c", "sleep 1h" ] volumeMounts: - name: sec-ctx-vol mountPath: /data/demo securityContext: allowPrivilegeEscalation: false In the configuration file, the runAsUser field specifies that for any Containers in the Pod, all processes run with user ID 1000. The runAsGroup field specifies the primary group ID of 3000 for all processes within any containers of the Pod. If this field is omitted, the primary group ID of the containers will be root(0). Any files created will also be owned by user 1000 and group 3000 when runAsGroup is specified. Since fsGroup field is specified, all processes of the container are also part of the supplementary group ID 2000. The owner for volume /data/demo and any


Question: What is Configure a Security Context for a Pod or Container?

Answer: A   s e c u r i t y   c o n t e x t   d e f i n e s   p r i v i l e g e   a n d   a c c e s s   c o n t r o l   s e t t i n g s   f o r   a   P o d   o r   C o n t a i n e r .   S e c u r i t y   c o n t e x t   s e t t i n g s   i n c l u d e ,   b u t   a r e   n o t   l i m i t e d   t o :   D i s c r e t i o n a r y   A c c e s s   C o n t r o l :   P e r m i s s i o n   t o   a c c e s s   a n   o b j e c t ,   l i k e   a   f i l e ,   i s   b a s e d   o n   u s e r   I D   ( U I D )   a n d   g r o u p   I D   ( G I D ) . S e c u r i t y   E n h a n c e d   L i n u x   ( S E L i n u x ) :   O b j e c t s   a r e   a s s i g n e d   s e c u r i t y   l a b e l s . R u n n i n g   a s   p r i v i l e g e d   o r   u n p r i v i l e g e d . L i n u x   C a p a b i l i t i e s :   G i v e   a   p r o c e s s   s o m e   p r i v i l e g e s ,   b u t   n o t   a l l   t h e   p r i v i l e g e s   o f   t h e   r o o t   u s e r . A p p A r m o r :   U s e   p r o g r a m   p r o f i l e s   t o   r e s t r i c t   t h e   c a p a b i l i t i e s   o f   i n d i v i d u a l   p r o g r a m s . S e c c o m p :   F i l t e r   a   p r o c e s s ' s   s y s t e m   c a l l s . a l l o w P r i v i l e g e E s c a l a t i o n :   C o n t r o l s   w h e t h e r   a   p r o c e s s   c a n   g a i n   m o r e   p r i v i l e g e s   t h a n   i t s   p a r e n t   p r o c e s s .   T h i s   b o o l   d i r e c t l y   c o n t r o l s   w h e t h e r   t h e   n o _ n e w _ p r i v s   f l a g   g e t s   s e t   o n   t h e   c o n t a i n e r   p r o c e s s .   a l l o w P r i v i l e g e E s c a l a t i o n   i s   a l w a y s   t r u e   w h e n   t h e   c o n t a i n e r : i s   r u n   a s   p r i v i l e g e d ,   o r h a s   C A P _ S Y S _ A D M I N r e a d O n l y R o o t F i l e s y s t e m :   M o u n t s   t h e   c o n t a i n e r ' s   r o o t   f i l e s y s t e m   a s   r e a d - o n l y .   D i s c r e t i o n a r y   A c c e s s   C o n t r o l :


Question: What is Before you begin?

Answer: Y o u   n e e d   t o   h a v e   a   K u b e r n e t e s   c l u s t e r ,   a n d   t h e   k u b e c t l   c o m m a n d - l i n e   t o o l   m u s t   b e   c o n f i g u r e d   t o   c o m m u n i c a t e   w i t h   y o u r   c l u s t e r .   I t   i s   r e c o m m e n d e d   t o   r u n   t h i s   t u t o r i a l   o n   a   c l u s t e r   w i t h   a t   l e a s t   t w o   n o d e s   t h a t   a r e   n o t   a c t i n g   a s   c o n t r o l   p l a n e   h o s t s .   I f   y o u   d o   n o t   a l r e a d y   h a v e   a   c l u s t e r ,   y o u   c a n   c r e a t e   o n e   b y   u s i n g   m i n i k u b e   o r   y o u   c a n   u s e   o n e   o f   t h e s e   K u b e r n e t e s   p l a y g r o u n d s : i x i m i u z   L a b s K i l l e r c o d a K o d e K l o u d P l a y   w i t h   K u b e r n e t e s T o   c h e c k   t h e   v e r s i o n ,   e n t e r   k u b e c t l   v e r s i o n .   Y o u   n e e d   t o   h a v e   a   K u b e r n e t e s   c l u s t e r ,   a n d   t h e   k u b e c t l   c o m m a n d - l i n e   t o o l   m u s t   b e   c o n f i g u r e d   t o   c o m m u n i c a t e   w i t h   y o u r   c l u s t e r .   I t   i s   r e c o m m e n d e d   t o   r u n   t h i s   t u t o r i a l   o n   a   c l u s t e r   w i t h   a t   l e a s t   t w o   n o d e s   t h a t   a r e   n o t   a c t i n g   a s   c o n t r o l   p l a n e   h o s t s .   I f   y o u   d o   n o t   a l r e a d y   h a v e   a   c l u s t e r ,   y o u   c a n   c r e a t e   o n e   b y   u s i n g   m i n i k u b e   o r   y o u   c a n   u s e   o n e   o f   t h e s e   K u b e r n e t e s   p l a y g r o u n d s :   i x i m i u z   L a b s K i l l e r c o d a K o d e K l o u d P l a y   w i t h   K u b e r n e t e s   T o   c h e c k   t h e   v e r s i o n ,   e n t e r   k u b e c t l   v e r s i o n .


Question: What is Set the security context for a Pod?

Answer: T o   s p e c i f y   s e c u r i t y   s e t t i n g s   f o r   a   P o d ,   i n c l u d e   t h e   s e c u r i t y C o n t e x t   f i e l d   i n   t h e   P o d   s p e c i f i c a t i o n .   T h e   s e c u r i t y C o n t e x t   f i e l d   i s   a   P o d S e c u r i t y C o n t e x t   o b j e c t .   T h e   s e c u r i t y   s e t t i n g s   t h a t   y o u   s p e c i f y   f o r   a   P o d   a p p l y   t o   a l l   C o n t a i n e r s   i n   t h e   P o d .   H e r e   i s   a   c o n f i g u r a t i o n   f i l e   f o r   a   P o d   t h a t   h a s   a   s e c u r i t y C o n t e x t   a n d   a n   e m p t y D i r   v o l u m e :   a p i V e r s i o n :   v 1   k i n d :   P o d   m e t a d a t a :   n a m e :   s e c u r i t y - c o n t e x t - d e m o   s p e c :   s e c u r i t y C o n t e x t :   r u n A s U s e r :   1 0 0 0   r u n A s G r o u p :   3 0 0 0   f s G r o u p :   2 0 0 0   s u p p l e m e n t a l G r o u p s :   [ 4 0 0 0 ]   v o l u m e s :   -   n a m e :   s e c - c t x - v o l   e m p t y D i r :   { }   c o n t a i n e r s :   -   n a m e :   s e c - c t x - d e m o   i m a g e :   b u s y b o x : 1 . 2 8   c o m m a n d :   [   " s h " ,   " - c " ,   " s l e e p   1 h "   ]   v o l u m e M o u n t s :   -   n a m e :   s e c - c t x - v o l   m o u n t P a t h :   / d a t a / d e m o   s e c u r i t y C o n t e x t :   a l l o w P r i v i l e g e E s c a l a t i o n :   f a l s e   I n   t h e   c o n f i g u r a t i o n   f i l e ,   t h e   r u n A s U s e r   f i e l d   s p e c i f i e s   t h a t   f o r   a n y   C o n t a i n e r s   i n   t h e   P o d ,   a l l   p r o c e s s e s   r u n   w i t h   u s e r   I D   1 0 0 0 .   T h e   r u n A s G r o u p   f i e l d   s p e c i f i e s   t h e   p r i m a r y   g r o u p   I D   o f   3 0 0 0   f o r   a l l   p r o c e s s e s   w i t h i n   a n y   c o n t a i n e r s   o f   t h e   P o d .   I f   t h i s   f i e l d   i s   o m i t t e d ,   t h e


Question: What is Implicit group memberships defined in /etc/group in the container image?

Answer: B y   d e f a u l t ,   k u b e r n e t e s   m e r g e s   g r o u p   i n f o r m a t i o n   f r o m   t h e   P o d   w i t h   i n f o r m a t i o n   d e f i n e d   i n   / e t c / g r o u p   i n   t h e   c o n t a i n e r   i m a g e .   a p i V e r s i o n :   v 1   k i n d :   P o d   m e t a d a t a :   n a m e :   s e c u r i t y - c o n t e x t - d e m o   s p e c :   s e c u r i t y C o n t e x t :   r u n A s U s e r :   1 0 0 0   r u n A s G r o u p :   3 0 0 0   s u p p l e m e n t a l G r o u p s :   [ 4 0 0 0 ]   c o n t a i n e r s :   -   n a m e :   s e c - c t x - d e m o   i m a g e :   r e g i s t r y . k 8 s . i o / e 2 e - t e s t - i m a g e s / a g n h o s t : 2 . 4 5   c o m m a n d :   [   " s h " ,   " - c " ,   " s l e e p   1 h "   ]   s e c u r i t y C o n t e x t :   a l l o w P r i v i l e g e E s c a l a t i o n :   f a l s e   T h i s   P o d   s e c u r i t y   c o n t e x t   c o n t a i n s   r u n A s U s e r ,   r u n A s G r o u p   a n d   s u p p l e m e n t a l G r o u p s .   H o w e v e r ,   y o u   c a n   s e e   t h a t   t h e   a c t u a l   s u p p l e m e n t a r y   g r o u p s   a t t a c h e d   t o   t h e   c o n t a i n e r   p r o c e s s   w i l l   i n c l u d e   g r o u p   I D s   w h i c h   c o m e   f r o m   / e t c / g r o u p   i n   t h e   c o n t a i n e r   i m a g e .   C r e a t e   t h e   P o d :   k u b e c t l   a p p l y   - f   h t t p s : / / k 8 s . i o / e x a m p l e s / p o d s / s e c u r i t y / s e c u r i t y - c o n t e x t - 5 . y a m l   V e r i f y   t h a t   t h e   P o d ' s   C o n t a i n e r   i s   r u n n i n g :   k u b e c t l   g e t   p o d   s e c u r i t y - c o n t e x t - d e m o   G e t   a   s h e l l   t o   t h e   r u n n i n g   C o n t a i n e r :   k u b e c t l   e x e c   - i t   s e c u r i t y - c o n t e x t - d e m o   - -   s h   C h e c k   t h e   p r o c e s s   i d e n t i t y :   $   i d   T h e   o u t p u t   i s   s i m i l a


Question: What is Configure fine-grained SupplementalGroups control for a Pod?

Answer: T h i s   f e a t u r e   c a n   b e   e n a b l e d   b y   s e t t i n g   t h e   S u p p l e m e n t a l G r o u p s P o l i c y   f e a t u r e   g a t e   f o r   k u b e l e t   a n d   k u b e - a p i s e r v e r ,   a n d   s e t t i n g   t h e   . s p e c . s e c u r i t y C o n t e x t . s u p p l e m e n t a l G r o u p s P o l i c y   f i e l d   f o r   a   p o d .   T h e   s u p p l e m e n t a l G r o u p s P o l i c y   f i e l d   d e f i n e s   t h e   p o l i c y   f o r   c a l c u l a t i n g   t h e   s u p p l e m e n t a r y   g r o u p s   f o r   t h e   c o n t a i n e r   p r o c e s s e s   i n   a   p o d .   T h e r e   a r e   t w o   v a l i d   v a l u e s   f o r   t h i s   f i e l d :   M e r g e :   T h e   g r o u p   m e m b e r s h i p   d e f i n e d   i n   / e t c / g r o u p   f o r   t h e   c o n t a i n e r ' s   p r i m a r y   u s e r   w i l l   b e   m e r g e d .   T h i s   i s   t h e   d e f a u l t   p o l i c y   i f   n o t   s p e c i f i e d . S t r i c t :   O n l y   g r o u p   I D s   i n   f s G r o u p ,   s u p p l e m e n t a l G r o u p s ,   o r   r u n A s G r o u p   f i e l d s   a r e   a t t a c h e d   a s   t h e   s u p p l e m e n t a r y   g r o u p s   o f   t h e   c o n t a i n e r   p r o c e s s e s .   T h i s   m e a n s   n o   g r o u p   m e m b e r s h i p   f r o m   / e t c / g r o u p   f o r   t h e   c o n t a i n e r ' s   p r i m a r y   u s e r   w i l l   b e   m e r g e d .   M e r g e :   T h e   g r o u p   m e m b e r s h i p   d e f i n e d   i n   / e t c / g r o u p   f o r   t h e   c o n t a i n e r ' s   p r i m a r y   u s e r   w i l l   b e   m e r g e d .   T h i s   i s   t h e   d e f a u l t   p o l i c y   i f   n o t   s p e c i f i e d .   S t r i c t :   O n l y   g r o u p   I D s   i n   f s G r o u p ,   s u p p l e m e n t a l G r o u p s ,   o r   r u n A s G r o u p   f i e l d s   a r e   a t t a c h e d   a s   t h e   s u p p l e m


Question: What is Implementations?

Answer: T h e   f o l l o w i n g   c o n t a i n e r   r u n t i m e s   a r e   k n o w n   t o   s u p p o r t   f i n e - g r a i n e d   S u p p l e m e n t a l G r o u p s   c o n t r o l .   C R I - l e v e l :   c o n t a i n e r d ,   s i n c e   v 2 . 0 C R I - O ,   s i n c e   v 1 . 3 1   Y o u   c a n   s e e   i f   t h e   f e a t u r e   i s   s u p p o r t e d   i n   t h e   N o d e   s t a t u s .   a p i V e r s i o n :   v 1   k i n d :   N o d e   . . .   s t a t u s :   f e a t u r e s :   s u p p l e m e n t a l G r o u p s P o l i c y :   t r u e


Question: What is Note:?

Answer: A t   t h i s   a l p h a   r e l e a s e ( f r o m   v 1 . 3 1   t o   v 1 . 3 2 ) ,   w h e n   a   p o d   w i t h   S u p p l e m e n t a l G r o u p s P o l i c y = S t r i c t   a r e   s c h e d u l e d   t o   a   n o d e   t h a t   d o e s   N O T   s u p p o r t   t h i s   f e a t u r e ( i . e .   . s t a t u s . f e a t u r e s . s u p p l e m e n t a l G r o u p s P o l i c y = f a l s e ) ,   t h e   p o d ' s   s u p p l e m e n t a l   g r o u p s   p o l i c y   f a l l s   b a c k   t o   t h e   M e r g e   p o l i c y   s i l e n t l y .   H o w e v e r ,   s i n c e   t h e   b e t a   r e l e a s e   ( v 1 . 3 3 ) ,   t o   e n f o r c e   t h e   p o l i c y   m o r e   s t r i c t l y ,   s u c h   p o d   c r e a t i o n   w i l l   b e   r e j e c t e d   b y   k u b e l e t   b e c a u s e   t h e   n o d e   c a n n o t   e n s u r e   t h e   s p e c i f i e d   p o l i c y .   W h e n   y o u r   p o d   i s   r e j e c t e d ,   y o u   w i l l   s e e   w a r n i n g   e v e n t s   w i t h   r e a s o n = S u p p l e m e n t a l G r o u p s P o l i c y N o t S u p p o r t e d   l i k e   b e l o w :   a p i V e r s i o n :   v 1   k i n d :   E v e n t   . . .   t y p e :   W a r n i n g   r e a s o n :   S u p p l e m e n t a l G r o u p s P o l i c y N o t S u p p o r t e d   m e s s a g e :   " S u p p l e m e n t a l G r o u p s P o l i c y = S t r i c t   i s   n o t   s u p p o r t e d   i n   t h i s   n o d e "   i n v o l v e d O b j e c t :   a p i V e r s i o n :   v 1   k i n d :   P o d   . . .


Question: What is Configure volume permission and ownership change policy for Pods?

Answer: B y   d e f a u l t ,   K u b e r n e t e s   r e c u r s i v e l y   c h a n g e s   o w n e r s h i p   a n d   p e r m i s s i o n s   f o r   t h e   c o n t e n t s   o f   e a c h   v o l u m e   t o   m a t c h   t h e   f s G r o u p   s p e c i f i e d   i n   a   P o d ' s   s e c u r i t y C o n t e x t   w h e n   t h a t   v o l u m e   i s   m o u n t e d .   F o r   l a r g e   v o l u m e s ,   c h e c k i n g   a n d   c h a n g i n g   o w n e r s h i p   a n d   p e r m i s s i o n s   c a n   t a k e   a   l o t   o f   t i m e ,   s l o w i n g   P o d   s t a r t u p .   Y o u   c a n   u s e   t h e   f s G r o u p C h a n g e P o l i c y   f i e l d   i n s i d e   a   s e c u r i t y C o n t e x t   t o   c o n t r o l   t h e   w a y   t h a t   K u b e r n e t e s   c h e c k s   a n d   m a n a g e s   o w n e r s h i p   a n d   p e r m i s s i o n s   f o r   a   v o l u m e .   f s G r o u p C h a n g e P o l i c y   -   f s G r o u p C h a n g e P o l i c y   d e f i n e s   b e h a v i o r   f o r   c h a n g i n g   o w n e r s h i p   a n d   p e r m i s s i o n   o f   t h e   v o l u m e   b e f o r e   b e i n g   e x p o s e d   i n s i d e   a   P o d .   T h i s   f i e l d   o n l y   a p p l i e s   t o   v o l u m e   t y p e s   t h a t   s u p p o r t   f s G r o u p   c o n t r o l l e d   o w n e r s h i p   a n d   p e r m i s s i o n s .   T h i s   f i e l d   h a s   t w o   p o s s i b l e   v a l u e s :   O n R o o t M i s m a t c h :   O n l y   c h a n g e   p e r m i s s i o n s   a n d   o w n e r s h i p   i f   t h e   p e r m i s s i o n   a n d   t h e   o w n e r s h i p   o f   r o o t   d i r e c t o r y   d o e s   n o t   m a t c h   w i t h   e x p e c t e d   p e r m i s s i o n s   o f   t h e   v o l u m e .   T h i s   c o u l d   h e l p   s h o r t e n   t h e   t i m e   i t   t a k e s   t o   c h a n g e   o w n e r s h i p   a n d   p e r m i s s i o n   o f   a   v o l u m e . A l w a y


Question: What is Delegating volume permission and ownership change to CSI driver?

Answer: I f   y o u   d e p l o y   a   C o n t a i n e r   S t o r a g e   I n t e r f a c e   ( C S I )   d r i v e r   w h i c h   s u p p o r t s   t h e   V O L U M E _ M O U N T _ G R O U P   N o d e S e r v i c e C a p a b i l i t y ,   t h e   p r o c e s s   o f   s e t t i n g   f i l e   o w n e r s h i p   a n d   p e r m i s s i o n s   b a s e d   o n   t h e   f s G r o u p   s p e c i f i e d   i n   t h e   s e c u r i t y C o n t e x t   w i l l   b e   p e r f o r m e d   b y   t h e   C S I   d r i v e r   i n s t e a d   o f   K u b e r n e t e s .   I n   t h i s   c a s e ,   s i n c e   K u b e r n e t e s   d o e s n ' t   p e r f o r m   a n y   o w n e r s h i p   a n d   p e r m i s s i o n   c h a n g e ,   f s G r o u p C h a n g e P o l i c y   d o e s   n o t   t a k e   e f f e c t ,   a n d   a s   s p e c i f i e d   b y   C S I ,   t h e   d r i v e r   i s   e x p e c t e d   t o   m o u n t   t h e   v o l u m e   w i t h   t h e   p r o v i d e d   f s G r o u p ,   r e s u l t i n g   i n   a   v o l u m e   t h a t   i s   r e a d a b l e / w r i t a b l e   b y   t h e   f s G r o u p .


Question: What is Set the security context for a Container?

Answer: T o   s p e c i f y   s e c u r i t y   s e t t i n g s   f o r   a   C o n t a i n e r ,   i n c l u d e   t h e   s e c u r i t y C o n t e x t   f i e l d   i n   t h e   C o n t a i n e r   m a n i f e s t .   T h e   s e c u r i t y C o n t e x t   f i e l d   i s   a   S e c u r i t y C o n t e x t   o b j e c t .   S e c u r i t y   s e t t i n g s   t h a t   y o u   s p e c i f y   f o r   a   C o n t a i n e r   a p p l y   o n l y   t o   t h e   i n d i v i d u a l   C o n t a i n e r ,   a n d   t h e y   o v e r r i d e   s e t t i n g s   m a d e   a t   t h e   P o d   l e v e l   w h e n   t h e r e   i s   o v e r l a p .   C o n t a i n e r   s e t t i n g s   d o   n o t   a f f e c t   t h e   P o d ' s   V o l u m e s .   H e r e   i s   t h e   c o n f i g u r a t i o n   f i l e   f o r   a   P o d   t h a t   h a s   o n e   C o n t a i n e r .   B o t h   t h e   P o d   a n d   t h e   C o n t a i n e r   h a v e   a   s e c u r i t y C o n t e x t   f i e l d :   a p i V e r s i o n :   v 1   k i n d :   P o d   m e t a d a t a :   n a m e :   s e c u r i t y - c o n t e x t - d e m o - 2   s p e c :   s e c u r i t y C o n t e x t :   r u n A s U s e r :   1 0 0 0   c o n t a i n e r s :   -   n a m e :   s e c - c t x - d e m o - 2   i m a g e :   g c r . i o / g o o g l e - s a m p l e s / h e l l o - a p p : 2 . 0   s e c u r i t y C o n t e x t :   r u n A s U s e r :   2 0 0 0   a l l o w P r i v i l e g e E s c a l a t i o n :   f a l s e   C r e a t e   t h e   P o d :   k u b e c t l   a p p l y   - f   h t t p s : / / k 8 s . i o / e x a m p l e s / p o d s / s e c u r i t y / s e c u r i t y - c o n t e x t - 2 . y a m l   V e r i f y   t h a t   t h e   P o d ' s   C o n t a i n e r   i s   r u n n i n g :   k u b e c t l   g e t   p o d   s e c u r i t y - c o n t e x t - d e m o - 2   G e t   a   s h e l l   i n t o   t h e   r u n n i n g   C o n t a i n e r :   k u b e c t l   e x e c   - i t   s e c u r i t y - c o n t e


Question: What is Set capabilities for a Container?

Answer: W i t h   L i n u x   c a p a b i l i t i e s ,   y o u   c a n   g r a n t   c e r t a i n   p r i v i l e g e s   t o   a   p r o c e s s   w i t h o u t   g r a n t i n g   a l l   t h e   p r i v i l e g e s   o f   t h e   r o o t   u s e r .   T o   a d d   o r   r e m o v e   L i n u x   c a p a b i l i t i e s   f o r   a   C o n t a i n e r ,   i n c l u d e   t h e   c a p a b i l i t i e s   f i e l d   i n   t h e   s e c u r i t y C o n t e x t   s e c t i o n   o f   t h e   C o n t a i n e r   m a n i f e s t .   F i r s t ,   s e e   w h a t   h a p p e n s   w h e n   y o u   d o n ' t   i n c l u d e   a   c a p a b i l i t i e s   f i e l d .   H e r e   i s   c o n f i g u r a t i o n   f i l e   t h a t   d o e s   n o t   a d d   o r   r e m o v e   a n y   C o n t a i n e r   c a p a b i l i t i e s :   a p i V e r s i o n :   v 1   k i n d :   P o d   m e t a d a t a :   n a m e :   s e c u r i t y - c o n t e x t - d e m o - 3   s p e c :   c o n t a i n e r s :   -   n a m e :   s e c - c t x - 3   i m a g e :   g c r . i o / g o o g l e - s a m p l e s / h e l l o - a p p : 2 . 0   C r e a t e   t h e   P o d :   k u b e c t l   a p p l y   - f   h t t p s : / / k 8 s . i o / e x a m p l e s / p o d s / s e c u r i t y / s e c u r i t y - c o n t e x t - 3 . y a m l   V e r i f y   t h a t   t h e   P o d ' s   C o n t a i n e r   i s   r u n n i n g :   k u b e c t l   g e t   p o d   s e c u r i t y - c o n t e x t - d e m o - 3   G e t   a   s h e l l   i n t o   t h e   r u n n i n g   C o n t a i n e r :   k u b e c t l   e x e c   - i t   s e c u r i t y - c o n t e x t - d e m o - 3   - -   s h   I n   y o u r   s h e l l ,   l i s t   t h e   r u n n i n g   p r o c e s s e s :   p s   a u x   T h e   o u t p u t   s h o w s   t h e   p r o c e s s   I D s   ( P I D s )   f o r   t h e   C o n t a i n e r :   U S E R   P I D   % C P U   % M E M   V S Z   R S S   T T Y   S T A T   S T A R T   T I M E   C O M M A N D   r o o t   1


Question: What is Set the Seccomp Profile for a Container?

Answer: T o   s e t   t h e   S e c c o m p   p r o f i l e   f o r   a   C o n t a i n e r ,   i n c l u d e   t h e   s e c c o m p P r o f i l e   f i e l d   i n   t h e   s e c u r i t y C o n t e x t   s e c t i o n   o f   y o u r   P o d   o r   C o n t a i n e r   m a n i f e s t .   T h e   s e c c o m p P r o f i l e   f i e l d   i s   a   S e c c o m p P r o f i l e   o b j e c t   c o n s i s t i n g   o f   t y p e   a n d   l o c a l h o s t P r o f i l e .   V a l i d   o p t i o n s   f o r   t y p e   i n c l u d e   R u n t i m e D e f a u l t ,   U n c o n f i n e d ,   a n d   L o c a l h o s t .   l o c a l h o s t P r o f i l e   m u s t   o n l y   b e   s e t   i f   t y p e :   L o c a l h o s t .   I t   i n d i c a t e s   t h e   p a t h   o f   t h e   p r e - c o n f i g u r e d   p r o f i l e   o n   t h e   n o d e ,   r e l a t i v e   t o   t h e   k u b e l e t ' s   c o n f i g u r e d   S e c c o m p   p r o f i l e   l o c a t i o n   ( c o n f i g u r e d   w i t h   t h e   - - r o o t - d i r   f l a g ) .   H e r e   i s   a n   e x a m p l e   t h a t   s e t s   t h e   S e c c o m p   p r o f i l e   t o   t h e   n o d e ' s   c o n t a i n e r   r u n t i m e   d e f a u l t   p r o f i l e :   . . .   s e c u r i t y C o n t e x t :   s e c c o m p P r o f i l e :   t y p e :   R u n t i m e D e f a u l t   H e r e   i s   a n   e x a m p l e   t h a t   s e t s   t h e   S e c c o m p   p r o f i l e   t o   a   p r e - c o n f i g u r e d   f i l e   a t   < k u b e l e t - r o o t - d i r > / s e c c o m p / m y - p r o f i l e s / p r o f i l e - a l l o w . j s o n :   . . .   s e c u r i t y C o n t e x t :   s e c c o m p P r o f i l e :   t y p e :   L o c a l h o s t   l o c a l h o s t P r o f i l e :   m y - p r o f i l e s / p r o f i l e - a l l o w . j s o n


Question: What is Set the AppArmor Profile for a Container?

Answer: T o   s e t   t h e   A p p A r m o r   p r o f i l e   f o r   a   C o n t a i n e r ,   i n c l u d e   t h e   a p p A r m o r P r o f i l e   f i e l d   i n   t h e   s e c u r i t y C o n t e x t   s e c t i o n   o f   y o u r   C o n t a i n e r .   T h e   a p p A r m o r P r o f i l e   f i e l d   i s   a   A p p A r m o r P r o f i l e   o b j e c t   c o n s i s t i n g   o f   t y p e   a n d   l o c a l h o s t P r o f i l e .   V a l i d   o p t i o n s   f o r   t y p e   i n c l u d e   R u n t i m e D e f a u l t ( d e f a u l t ) ,   U n c o n f i n e d ,   a n d   L o c a l h o s t .   l o c a l h o s t P r o f i l e   m u s t   o n l y   b e   s e t   i f   t y p e   i s   L o c a l h o s t .   I t   i n d i c a t e s   t h e   n a m e   o f   t h e   p r e - c o n f i g u r e d   p r o f i l e   o n   t h e   n o d e .   T h e   p r o f i l e   n e e d s   t o   b e   l o a d e d   o n t o   a l l   n o d e s   s u i t a b l e   f o r   t h e   P o d ,   s i n c e   y o u   d o n ' t   k n o w   w h e r e   t h e   p o d   w i l l   b e   s c h e d u l e d .   A p p r o a c h e s   f o r   s e t t i n g   u p   c u s t o m   p r o f i l e s   a r e   d i s c u s s e d   i n   S e t t i n g   u p   n o d e s   w i t h   p r o f i l e s .   N o t e :   I f   c o n t a i n e r s [ * ] . s e c u r i t y C o n t e x t . a p p A r m o r P r o f i l e . t y p e   i s   e x p l i c i t l y   s e t   t o   R u n t i m e D e f a u l t ,   t h e n   t h e   P o d   w i l l   n o t   b e   a d m i t t e d   i f   A p p A r m o r   i s   n o t   e n a b l e d   o n   t h e   N o d e .   H o w e v e r   i f   c o n t a i n e r s [ * ] . s e c u r i t y C o n t e x t . a p p A r m o r P r o f i l e . t y p e   i s   n o t   s p e c i f i e d ,   t h e n   t h e   d e f a u l t   ( w h i c h   i s   a l s o   R u n t i m e D e f a u l t )   w i l l   o n l y   b e   a p p l i e d   i f   t h e   n o d e   h a s   A p p A r m o r   e n a b l e d .   I f   t h


Question: What is Assign SELinux labels to a Container?

Answer: T o   a s s i g n   S E L i n u x   l a b e l s   t o   a   C o n t a i n e r ,   i n c l u d e   t h e   s e L i n u x O p t i o n s   f i e l d   i n   t h e   s e c u r i t y C o n t e x t   s e c t i o n   o f   y o u r   P o d   o r   C o n t a i n e r   m a n i f e s t .   T h e   s e L i n u x O p t i o n s   f i e l d   i s   a n   S E L i n u x O p t i o n s   o b j e c t .   H e r e ' s   a n   e x a m p l e   t h a t   a p p l i e s   a n   S E L i n u x   l e v e l :   . . .   s e c u r i t y C o n t e x t :   s e L i n u x O p t i o n s :   l e v e l :   " s 0 : c 1 2 3 , c 4 5 6 "


Question: What is Note:?

Answer: K u b e r n e t e s   v 1 . 2 7   i n t r o d u c e d   a n   e a r l y   l i m i t e d   f o r m   o f   t h i s   b e h a v i o r   t h a t   w a s   o n l y   a p p l i c a b l e   t o   v o l u m e s   ( a n d   P e r s i s t e n t V o l u m e C l a i m s )   u s i n g   t h e   R e a d W r i t e O n c e P o d   a c c e s s   m o d e .   K u b e r n e t e s   v 1 . 3 3   p r o m o t e s   S E L i n u x C h a n g e P o l i c y   a n d   S E L i n u x M o u n t   f e a t u r e   g a t e s   a s   b e t a   t o   w i d e n   t h a t   p e r f o r m a n c e   i m p r o v e m e n t   t o   o t h e r   k i n d s   o f   P e r s i s t e n t V o l u m e C l a i m s ,   a s   e x p l a i n e d   i n   d e t a i l   b e l o w .   W h i l e   i n   b e t a ,   S E L i n u x M o u n t   i s   s t i l l   d i s a b l e d   b y   d e f a u l t .   W i t h   S E L i n u x M o u n t   f e a t u r e   g a t e   d i s a b l e d   ( t h e   d e f a u l t   i n   K u b e r n e t e s   1 . 3 3   a n d   a n y   p r e v i o u s   r e l e a s e ) ,   t h e   c o n t a i n e r   r u n t i m e   r e c u r s i v e l y   a s s i g n s   S E L i n u x   l a b e l   t o   a l l   f i l e s   o n   a l l   P o d   v o l u m e s   b y   d e f a u l t .   T o   s p e e d   u p   t h i s   p r o c e s s ,   K u b e r n e t e s   c a n   c h a n g e   t h e   S E L i n u x   l a b e l   o f   a   v o l u m e   i n s t a n t l y   b y   u s i n g   a   m o u n t   o p t i o n   - o   c o n t e x t = < l a b e l > .   T o   b e n e f i t   f r o m   t h i s   s p e e d u p ,   a l l   t h e s e   c o n d i t i o n s   m u s t   b e   m e t :   T h e   f e a t u r e   g a t e   S E L i n u x M o u n t R e a d W r i t e O n c e P o d   m u s t   b e   e n a b l e d . P o d   m u s t   u s e   P e r s i s t e n t V o l u m e C l a i m   w i t h   a p p l i c a b l e   a c c e s s M o d e s   a n d   f e a t u r e   g a t e s : E i t h e r   t h e   v o l u m e   h a s   a c c e s s M o d e s :   [ "


Question: What is SELinuxWarningController?

Answer: T o   m a k e   i t   e a s i e r   t o   i d e n t i f y   P o d s   t h a t   a r e   a f f e c t e d   b y   t h e   c h a n g e   i n   S E L i n u x   v o l u m e   r e l a b e l i n g ,   a   n e w   c o n t r o l l e r   c a l l e d   S E L i n u x W a r n i n g C o n t r o l l e r   h a s   b e e n   i n t r o d u c e d   i n   k u b e - c o n t r o l l e r - m a n a g e r .   I t   i s   d i s a b l e d   b y   d e f a u l t   a n d   c a n   b e   e n a b l e d   b y   e i t h e r   s e t t i n g   t h e   - - c o n t r o l l e r s = * , s e l i n u x - w a r n i n g - c o n t r o l l e r   c o m m a n d   l i n e   f l a g ,   o r   b y   s e t t i n g   g e n e r i c C o n t r o l l e r M a n a g e r C o n f i g u r a t i o n . c o n t r o l l e r s   f i e l d   i n   K u b e C o n t r o l l e r M a n a g e r C o n f i g u r a t i o n .   T h i s   c o n t r o l l e r   r e q u i r e s   S E L i n u x C h a n g e P o l i c y   f e a t u r e   g a t e   t o   b e   e n a b l e d .   W h e n   e n a b l e d ,   t h e   c o n t r o l l e r   o b s e r v e s   r u n n i n g   P o d s   a n d   w h e n   i t   d e t e c t s   t h a t   t w o   P o d s   u s e   t h e   s a m e   v o l u m e   w i t h   d i f f e r e n t   S E L i n u x   l a b e l s :   I t   e m i t s   a n   e v e n t   t o   b o t h   o f   t h e   P o d s .   k u b e c t l   d e s c r i b e   p o d   < p o d - n a m e >   t h e   s h o w s   S E L i n u x L a b e l   " < l a b e l   o n   t h e   p o d > "   c o n f l i c t s   w i t h   p o d   < t h e   o t h e r   p o d   n a m e >   t h a t   u s e s   t h e   s a m e   v o l u m e   a s   t h i s   p o d   w i t h   S E L i n u x L a b e l   " < t h e   o t h e r   p o d   l a b e l > " .   I f   b o t h   p o d s   l a n d   o n   t h e   s a m e   n o d e ,   o n l y   o n e   o f   t h e m   m a y   a c c e s s   t h e   v o l u m e . R a i s e   s e l i n u x _ w a r n i n g _ c o n t r o l l e r _ s e l i n u x _ v o l u m e _


Question: What is Feature gates?

Answer: T h e   f o l l o w i n g   f e a t u r e   g a t e s   c o n t r o l   t h e   b e h a v i o r   o f   S E L i n u x   v o l u m e   r e l a b e l i n g :   S E L i n u x M o u n t R e a d W r i t e O n c e P o d :   e n a b l e s   t h e   o p t i m i z a t i o n   f o r   v o l u m e s   w i t h   a c c e s s M o d e s :   [ " R e a d W r i t e O n c e P o d " ] .   T h i s   i s   a   v e r y   s a f e   f e a t u r e   g a t e   t o   e n a b l e ,   a s   i t   c a n n o t   h a p p e n   t h a t   t w o   p o d s   c a n   s h a r e   o n e   s i n g l e   v o l u m e   w i t h   t h i s   a c c e s s   m o d e .   T h i s   f e a t u r e   g a t e   i s   e n a b l e d   b y   d e f a u l t   s i n e   v 1 . 2 8 . S E L i n u x C h a n g e P o l i c y :   e n a b l e s   s p e c . s e c u r i t y C o n t e x t . s e L i n u x C h a n g e P o l i c y   f i e l d   i n   P o d   a n d   r e l a t e d   S E L i n u x W a r n i n g C o n t r o l l e r   i n   k u b e - c o n t r o l l e r - m a n a g e r .   T h i s   f e a t u r e   c a n   b e   u s e d   b e f o r e   e n a b l i n g   S E L i n u x M o u n t   t o   c h e c k   P o d s   r u n n i n g   o n   a   c l u s t e r ,   a n d   t o   p r o - a c t i v e l y   o p t - o u t   P o d s   f r o m   t h e   o p t i m i z a t i o n .   T h i s   f e a t u r e   g a t e   r e q u i r e s   S E L i n u x M o u n t R e a d W r i t e O n c e P o d   e n a b l e d .   I t   i s   b e t a   a n d   e n a b l e d   b y   d e f a u l t   i n   1 . 3 3 . S E L i n u x M o u n t   e n a b l e s   t h e   o p t i m i z a t i o n   f o r   a l l   e l i g i b l e   v o l u m e s .   S i n c e   i t   c a n   b r e a k   e x i s t i n g   w o r k l o a d s ,   w e   r e c o m m e n d   e n a b l i n g   S E L i n u x C h a n g e P o l i c y   f e a t u r e   g a t e   +   S E L i n u x W a r n i n g C o n t r o l l e r   f i r s t   t o   c h e c k   t h e   i m p a c t   o f   t h e   c h a n g e .   T h i s   f e


Question: What is Managing access to the /proc filesystem?

Answer: F o r   r u n t i m e s   t h a t   f o l l o w   t h e   O C I   r u n t i m e   s p e c i f i c a t i o n ,   c o n t a i n e r s   d e f a u l t   t o   r u n n i n g   i n   a   m o d e   w h e r e   t h e r e   a r e   m u l t i p l e   p a t h s   t h a t   a r e   b o t h   m a s k e d   a n d   r e a d - o n l y .   T h e   r e s u l t   o f   t h i s   i s   t h e   c o n t a i n e r   h a s   t h e s e   p a t h s   p r e s e n t   i n s i d e   t h e   c o n t a i n e r ' s   m o u n t   n a m e s p a c e ,   a n d   t h e y   c a n   f u n c t i o n   s i m i l a r l y   t o   i f   t h e   c o n t a i n e r   w a s   a n   i s o l a t e d   h o s t ,   b u t   t h e   c o n t a i n e r   p r o c e s s   c a n n o t   w r i t e   t o   t h e m .   T h e   l i s t   o f   m a s k e d   a n d   r e a d - o n l y   p a t h s   a r e   a s   f o l l o w s :   M a s k e d   P a t h s : / p r o c / a s o u n d / p r o c / a c p i / p r o c / k c o r e / p r o c / k e y s / p r o c / l a t e n c y _ s t a t s / p r o c / t i m e r _ l i s t / p r o c / t i m e r _ s t a t s / p r o c / s c h e d _ d e b u g / p r o c / s c s i / s y s / f i r m w a r e / s y s / d e v i c e s / v i r t u a l / p o w e r c a p R e a d - O n l y   P a t h s : / p r o c / b u s / p r o c / f s / p r o c / i r q / p r o c / s y s / p r o c / s y s r q - t r i g g e r   M a s k e d   P a t h s :   / p r o c / a s o u n d / p r o c / a c p i / p r o c / k c o r e / p r o c / k e y s / p r o c / l a t e n c y _ s t a t s / p r o c / t i m e r _ l i s t / p r o c / t i m e r _ s t a t s / p r o c / s c h e d _ d e b u g / p r o c / s c s i / s y s / f i r m w a r e / s y s / d e v i c e s / v i r t u a l / p o w e r c a p   R e a d - O n l y   P a t h s :   / p r o c / b u s / p r o c / f s / p r o c / i r q / p r o c / s y s / p r o c / s y s r q - t r i g g e r   F o r   s o m e   P o d s ,   y o u   m i g h t   w a n t   t o   b y p a s s   t h a t   d e f a u l t   m a s k i n g


Question: What is Discussion?

Answer: T h e   s e c u r i t y   c o n t e x t   f o r   a   P o d   a p p l i e s   t o   t h e   P o d ' s   C o n t a i n e r s   a n d   a l s o   t o   t h e   P o d ' s   V o l u m e s   w h e n   a p p l i c a b l e .   S p e c i f i c a l l y   f s G r o u p   a n d   s e L i n u x O p t i o n s   a r e   a p p l i e d   t o   V o l u m e s   a s   f o l l o w s :   f s G r o u p :   V o l u m e s   t h a t   s u p p o r t   o w n e r s h i p   m a n a g e m e n t   a r e   m o d i f i e d   t o   b e   o w n e d   a n d   w r i t a b l e   b y   t h e   G I D   s p e c i f i e d   i n   f s G r o u p .   S e e   t h e   O w n e r s h i p   M a n a g e m e n t   d e s i g n   d o c u m e n t   f o r   m o r e   d e t a i l s . s e L i n u x O p t i o n s :   V o l u m e s   t h a t   s u p p o r t   S E L i n u x   l a b e l i n g   a r e   r e l a b e l e d   t o   b e   a c c e s s i b l e   b y   t h e   l a b e l   s p e c i f i e d   u n d e r   s e L i n u x O p t i o n s .   U s u a l l y   y o u   o n l y   n e e d   t o   s e t   t h e   l e v e l   s e c t i o n .   T h i s   s e t s   t h e   M u l t i - C a t e g o r y   S e c u r i t y   ( M C S )   l a b e l   g i v e n   t o   a l l   C o n t a i n e r s   i n   t h e   P o d   a s   w e l l   a s   t h e   V o l u m e s .   f s G r o u p :   V o l u m e s   t h a t   s u p p o r t   o w n e r s h i p   m a n a g e m e n t   a r e   m o d i f i e d   t o   b e   o w n e d   a n d   w r i t a b l e   b y   t h e   G I D   s p e c i f i e d   i n   f s G r o u p .   S e e   t h e   O w n e r s h i p   M a n a g e m e n t   d e s i g n   d o c u m e n t   f o r   m o r e   d e t a i l s .   s e L i n u x O p t i o n s :   V o l u m e s   t h a t   s u p p o r t   S E L i n u x   l a b e l i n g   a r e   r e l a b e l e d   t o   b e   a c c e s s i b l e   b y   t h e   l a b e l   s p e c i f i e d   u n d e r   s e L i n u x O p t i o n s .   U s u a l l y   y o u   o n l y   n e e d   t o   s e t


Question: What is Clean up?

Answer: D e l e t e   t h e   P o d :   k u b e c t l   d e l e t e   p o d   s e c u r i t y - c o n t e x t - d e m o   k u b e c t l   d e l e t e   p o d   s e c u r i t y - c o n t e x t - d e m o - 2   k u b e c t l   d e l e t e   p o d   s e c u r i t y - c o n t e x t - d e m o - 3   k u b e c t l   d e l e t e   p o d   s e c u r i t y - c o n t e x t - d e m o - 4


Question: What is What's next?

Answer: P o d S e c u r i t y C o n t e x t S e c u r i t y C o n t e x t C R I   P l u g i n   C o n f i g   G u i d e S e c u r i t y   C o n t e x t s   d e s i g n   d o c u m e n t O w n e r s h i p   M a n a g e m e n t   d e s i g n   d o c u m e n t P o d S e c u r i t y   A d m i s s i o n A l l o w P r i v i l e g e E s c a l a t i o n   d e s i g n   d o c u m e n t F o r   m o r e   i n f o r m a t i o n   a b o u t   s e c u r i t y   m e c h a n i s m s   i n   L i n u x ,   s e e   O v e r v i e w   o f   L i n u x   K e r n e l   S e c u r i t y   F e a t u r e s   ( N o t e :   S o m e   i n f o r m a t i o n   i s   o u t   o f   d a t e ) R e a d   a b o u t   U s e r   N a m e s p a c e s   f o r   L i n u x   p o d s . M a s k e d   P a t h s   i n   t h e   O C I   R u n t i m e   S p e c i f i c a t i o n   I t e m s   o n   t h i s   p a g e   r e f e r   t o   t h i r d   p a r t y   p r o d u c t s   o r   p r o j e c t s   t h a t   p r o v i d e   f u n c t i o n a l i t y   r e q u i r e d   b y   K u b e r n e t e s .   T h e   K u b e r n e t e s   p r o j e c t   a u t h o r s   a r e n ' t   r e s p o n s i b l e   f o r   t h o s e   t h i r d - p a r t y   p r o d u c t s   o r   p r o j e c t s .   S e e   t h e   C N C F   w e b s i t e   g u i d e l i n e s   f o r   m o r e   d e t a i l s .   Y o u   s h o u l d   r e a d   t h e   c o n t e n t   g u i d e   b e f o r e   p r o p o s i n g   a   c h a n g e   t h a t   a d d s   a n   e x t r a   t h i r d - p a r t y   l i n k .


Question: What is Extend Service IP Ranges?

Answer: Extend Service IP RangesFEATURE STATE: Kubernetes v1.33 [stable] (enabled by default: true)This document shares how to extend the existing Service IP range assigned to a cluster.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesYour Kubernetes server must be at or later than version v1.29.To check the version, enter kubectl version.Note:While you can use this feature with an earlier version, the feature is only GA and officially supported since v1.33.Extend Service IP RangesKubernetes clusters with kube-apiservers that have enabled the MultiCIDRServiceAllocator feature gate and have the networking.k8s.io/v1beta1 API group active, will create a ServiceCIDR object that takes the well-known name kubernetes, and that specifies an IP address range based on the value of the --service-cluster-ip-range command line argument to kube-apiserver.kubectl get servicecidr NAME CIDRS AGE kubernetes 10.96.0.0/28 17d The well-known kubernetes Service, that exposes the kube-apiserver endpoint to the Pods, calculates the first IP address from the default ServiceCIDR range and uses that IP address as its cluster IP address.kubectl get service kubernetes NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 17d The default Service, in this case, uses the ClusterIP 10.96.0.1, that has the corresponding IPAddress object.kubectl get ipaddress 10.96.0.1 NAME PARENTREF 10.96.0.1 services/default/kubernetes The ServiceCIDRs are protected with finalizers, to avoid leaving Service ClusterIPs orphans; the finalizer is only removed if there is another subnet that contains the existing IPAddresses or there are no IPAddresses belonging to the subnet.Extend the number of available IPs for ServicesThere are cases that users will need to increase the number addresses available to Services, previously, increasing the Service range was a disruptive operation that could also cause data loss. With this new feature users only need to add a new ServiceCIDR to increase the number of available addresses.Adding a new ServiceCIDROn a cluster with a 10.96.0.0/28 range for Services, there is only 2^(32-28) - 2 = 14 IP addresses available. The kubernetes.default Service is always created; for this example, that leaves you with only 13 possible Services.for i in $(seq 1 13); do kubectl create service clusterip "test-$i" --tcp 80 -o json | jq -r .spec.clusterIP; done 10.96.0.11 10.96.0.5 10.96.0.12 10.96.0.13 10.96.0.14 10.96.0.2 10.96.0.3 10.96.0.4 10.96.0.6 10.96.0.7 10.96.0.8 10.96.0.9 error: failed to create ClusterIP service: Internal error occurred: failed to allocate a ser


Question: How does Extend Service IP Ranges work?

Answer: Extend Service IP RangesFEATURE STATE: Kubernetes v1.33 [stable] (enabled by default: true)This document shares how to extend the existing Service IP range assigned to a cluster.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesYour Kubernetes server must be at or later than version v1.29.To check the version, enter kubectl version.Note:While you can use this feature with an earlier version, the feature is only GA and officially supported since v1.33.Extend Service IP RangesKubernetes clusters with kube-apiservers that have enabled the MultiCIDRServiceAllocator feature gate and have the networking.k8s.io/v1beta1 API group active, will create a ServiceCIDR object that takes the well-known name kubernetes, and that specifies an IP address range based on the value of the --service-cluster-ip-range command line argument to kube-apiserver.kubectl get servicecidr NAME CIDRS AGE kubernetes 10.96.0.0/28 17d The well-known kubernetes Service, that exposes the kube-apiserver endpoint to the Pods, calculates the first IP address from the default ServiceCIDR range and uses that IP address as its cluster IP address.kubectl get service kubernetes NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 17d The default Service, in this case, uses the ClusterIP 10.96.0.1, that has the corresponding IPAddress object.kubectl get ipaddress 10.96.0.1 NAME PARENTREF 10.96.0.1 services/default/kubernetes The ServiceCIDRs are protected with finalizers, to avoid leaving Service ClusterIPs orphans; the finalizer is only removed if there is another subnet that contains the existing IPAddresses or there are no IPAddresses belonging to the subnet.Extend the number of available IPs for ServicesThere are cases that users will need to increase the number addresses available to Services, previously, increasing the Service range was a disruptive operation that could also cause data loss. With this new feature users only need to add a new ServiceCIDR to increase the number of available addresses.Adding a new ServiceCIDROn a cluster with a 10.96.0.0/28 range for Services, there is only 2^(32-28) - 2 = 14 IP addresses available. The kubernetes.default Service is always created; for this example, that leaves you with only 13 possible Services.for i in $(seq 1 13); do kubectl create service clusterip "test-$i" --tcp 80 -o json | jq -r .spec.clusterIP; done 10.96.0.11 10.96.0.5 10.96.0.12 10.96.0.13 10.96.0.14 10.96.0.2 10.96.0.3 10.96.0.4 10.96.0.6 10.96.0.7 10.96.0.8 10.96.0.9 error: failed to create ClusterIP service: Internal error occurred: failed to allocate a ser


Question: When would you use Extend Service IP Ranges?

Answer: Extend Service IP RangesFEATURE STATE: Kubernetes v1.33 [stable] (enabled by default: true)This document shares how to extend the existing Service IP range assigned to a cluster.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesYour Kubernetes server must be at or later than version v1.29.To check the version, enter kubectl version.Note:While you can use this feature with an earlier version, the feature is only GA and officially supported since v1.33.Extend Service IP RangesKubernetes clusters with kube-apiservers that have enabled the MultiCIDRServiceAllocator feature gate and have the networking.k8s.io/v1beta1 API group active, will create a ServiceCIDR object that takes the well-known name kubernetes, and that specifies an IP address range based on the value of the --service-cluster-ip-range command line argument to kube-apiserver.kubectl get servicecidr NAME CIDRS AGE kubernetes 10.96.0.0/28 17d The well-known kubernetes Service, that exposes the kube-apiserver endpoint to the Pods, calculates the first IP address from the default ServiceCIDR range and uses that IP address as its cluster IP address.kubectl get service kubernetes NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 17d The default Service, in this case, uses the ClusterIP 10.96.0.1, that has the corresponding IPAddress object.kubectl get ipaddress 10.96.0.1 NAME PARENTREF 10.96.0.1 services/default/kubernetes The ServiceCIDRs are protected with finalizers, to avoid leaving Service ClusterIPs orphans; the finalizer is only removed if there is another subnet that contains the existing IPAddresses or there are no IPAddresses belonging to the subnet.Extend the number of available IPs for ServicesThere are cases that users will need to increase the number addresses available to Services, previously, increasing the Service range was a disruptive operation that could also cause data loss. With this new feature users only need to add a new ServiceCIDR to increase the number of available addresses.Adding a new ServiceCIDROn a cluster with a 10.96.0.0/28 range for Services, there is only 2^(32-28) - 2 = 14 IP addresses available. The kubernetes.default Service is always created; for this example, that leaves you with only 13 possible Services.for i in $(seq 1 13); do kubectl create service clusterip "test-$i" --tcp 80 -o json | jq -r .spec.clusterIP; done 10.96.0.11 10.96.0.5 10.96.0.12 10.96.0.13 10.96.0.14 10.96.0.2 10.96.0.3 10.96.0.4 10.96.0.6 10.96.0.7 10.96.0.8 10.96.0.9 error: failed to create ClusterIP service: Internal error occurred: failed to allocate a ser


Question: What are the benefits of Extend Service IP Ranges?

Answer: Extend Service IP RangesFEATURE STATE: Kubernetes v1.33 [stable] (enabled by default: true)This document shares how to extend the existing Service IP range assigned to a cluster.Before you beginYou need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:iximiuz LabsKillercodaKodeKloudPlay with KubernetesYour Kubernetes server must be at or later than version v1.29.To check the version, enter kubectl version.Note:While you can use this feature with an earlier version, the feature is only GA and officially supported since v1.33.Extend Service IP RangesKubernetes clusters with kube-apiservers that have enabled the MultiCIDRServiceAllocator feature gate and have the networking.k8s.io/v1beta1 API group active, will create a ServiceCIDR object that takes the well-known name kubernetes, and that specifies an IP address range based on the value of the --service-cluster-ip-range command line argument to kube-apiserver.kubectl get servicecidr NAME CIDRS AGE kubernetes 10.96.0.0/28 17d The well-known kubernetes Service, that exposes the kube-apiserver endpoint to the Pods, calculates the first IP address from the default ServiceCIDR range and uses that IP address as its cluster IP address.kubectl get service kubernetes NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 17d The default Service, in this case, uses the ClusterIP 10.96.0.1, that has the corresponding IPAddress object.kubectl get ipaddress 10.96.0.1 NAME PARENTREF 10.96.0.1 services/default/kubernetes The ServiceCIDRs are protected with finalizers, to avoid leaving Service ClusterIPs orphans; the finalizer is only removed if there is another subnet that contains the existing IPAddresses or there are no IPAddresses belonging to the subnet.Extend the number of available IPs for ServicesThere are cases that users will need to increase the number addresses available to Services, previously, increasing the Service range was a disruptive operation that could also cause data loss. With this new feature users only need to add a new ServiceCIDR to increase the number of available addresses.Adding a new ServiceCIDROn a cluster with a 10.96.0.0/28 range for Services, there is only 2^(32-28) - 2 = 14 IP addresses available. The kubernetes.default Service is always created; for this example, that leaves you with only 13 possible Services.for i in $(seq 1 13); do kubectl create service clusterip "test-$i" --tcp 80 -o json | jq -r .spec.clusterIP; done 10.96.0.11 10.96.0.5 10.96.0.12 10.96.0.13 10.96.0.14 10.96.0.2 10.96.0.3 10.96.0.4 10.96.0.6 10.96.0.7 10.96.0.8 10.96.0.9 error: failed to create ClusterIP service: Internal error occurred: failed to allocate a ser


Question: What is Extend Service IP Ranges?

Answer: T h i s   d o c u m e n t   s h a r e s   h o w   t o   e x t e n d   t h e   e x i s t i n g   S e r v i c e   I P   r a n g e   a s s i g n e d   t o   a   c l u s t e r .


Question: What is Before you begin?

Answer: Y o u   n e e d   t o   h a v e   a   K u b e r n e t e s   c l u s t e r ,   a n d   t h e   k u b e c t l   c o m m a n d - l i n e   t o o l   m u s t   b e   c o n f i g u r e d   t o   c o m m u n i c a t e   w i t h   y o u r   c l u s t e r .   I t   i s   r e c o m m e n d e d   t o   r u n   t h i s   t u t o r i a l   o n   a   c l u s t e r   w i t h   a t   l e a s t   t w o   n o d e s   t h a t   a r e   n o t   a c t i n g   a s   c o n t r o l   p l a n e   h o s t s .   I f   y o u   d o   n o t   a l r e a d y   h a v e   a   c l u s t e r ,   y o u   c a n   c r e a t e   o n e   b y   u s i n g   m i n i k u b e   o r   y o u   c a n   u s e   o n e   o f   t h e s e   K u b e r n e t e s   p l a y g r o u n d s :   i x i m i u z   L a b s K i l l e r c o d a K o d e K l o u d P l a y   w i t h   K u b e r n e t e s   T o   c h e c k   t h e   v e r s i o n ,   e n t e r   k u b e c t l   v e r s i o n .


Question: What is Extend Service IP Ranges?

Answer: K u b e r n e t e s   c l u s t e r s   w i t h   k u b e - a p i s e r v e r s   t h a t   h a v e   e n a b l e d   t h e   M u l t i C I D R S e r v i c e A l l o c a t o r   f e a t u r e   g a t e   a n d   h a v e   t h e   n e t w o r k i n g . k 8 s . i o / v 1 b e t a 1   A P I   g r o u p   a c t i v e ,   w i l l   c r e a t e   a   S e r v i c e C I D R   o b j e c t   t h a t   t a k e s   t h e   w e l l - k n o w n   n a m e   k u b e r n e t e s ,   a n d   t h a t   s p e c i f i e s   a n   I P   a d d r e s s   r a n g e   b a s e d   o n   t h e   v a l u e   o f   t h e   - - s e r v i c e - c l u s t e r - i p - r a n g e   c o m m a n d   l i n e   a r g u m e n t   t o   k u b e - a p i s e r v e r .   k u b e c t l   g e t   s e r v i c e c i d r   N A M E   C I D R S   A G E   k u b e r n e t e s   1 0 . 9 6 . 0 . 0 / 2 8   1 7 d   T h e   w e l l - k n o w n   k u b e r n e t e s   S e r v i c e ,   t h a t   e x p o s e s   t h e   k u b e - a p i s e r v e r   e n d p o i n t   t o   t h e   P o d s ,   c a l c u l a t e s   t h e   f i r s t   I P   a d d r e s s   f r o m   t h e   d e f a u l t   S e r v i c e C I D R   r a n g e   a n d   u s e s   t h a t   I P   a d d r e s s   a s   i t s   c l u s t e r   I P   a d d r e s s .   k u b e c t l   g e t   s e r v i c e   k u b e r n e t e s   N A M E   T Y P E   C L U S T E R - I P   E X T E R N A L - I P   P O R T ( S )   A G E   k u b e r n e t e s   C l u s t e r I P   1 0 . 9 6 . 0 . 1   < n o n e >   4 4 3 / T C P   1 7 d   T h e   d e f a u l t   S e r v i c e ,   i n   t h i s   c a s e ,   u s e s   t h e   C l u s t e r I P   1 0 . 9 6 . 0 . 1 ,   t h a t   h a s   t h e   c o r r e s p o n d i n g   I P A d d r e s s   o b j e c t .   k u b e c t l   g e t   i p a d d r e s s   1 0 . 9 6 . 0 . 1   N A M E   P A R E N T R E F   1 0 . 9 6 . 0 . 1   s e r v i c e s / d e f a u l t / k u b e r n e t e s   T h e   S e r v i c e C I D R s   a r e   p r o t e c t e d   w i t h


Question: What is Extend the number of available IPs for Services?

Answer: T h e r e   a r e   c a s e s   t h a t   u s e r s   w i l l   n e e d   t o   i n c r e a s e   t h e   n u m b e r   a d d r e s s e s   a v a i l a b l e   t o   S e r v i c e s ,   p r e v i o u s l y ,   i n c r e a s i n g   t h e   S e r v i c e   r a n g e   w a s   a   d i s r u p t i v e   o p e r a t i o n   t h a t   c o u l d   a l s o   c a u s e   d a t a   l o s s .   W i t h   t h i s   n e w   f e a t u r e   u s e r s   o n l y   n e e d   t o   a d d   a   n e w   S e r v i c e C I D R   t o   i n c r e a s e   t h e   n u m b e r   o f   a v a i l a b l e   a d d r e s s e s .


Question: What is Adding a new ServiceCIDR?

Answer: O n   a   c l u s t e r   w i t h   a   1 0 . 9 6 . 0 . 0 / 2 8   r a n g e   f o r   S e r v i c e s ,   t h e r e   i s   o n l y   2 ^ ( 3 2 - 2 8 )   -   2   =   1 4   I P   a d d r e s s e s   a v a i l a b l e .   T h e   k u b e r n e t e s . d e f a u l t   S e r v i c e   i s   a l w a y s   c r e a t e d ;   f o r   t h i s   e x a m p l e ,   t h a t   l e a v e s   y o u   w i t h   o n l y   1 3   p o s s i b l e   S e r v i c e s .   f o r   i   i n   $ ( s e q   1   1 3 ) ;   d o   k u b e c t l   c r e a t e   s e r v i c e   c l u s t e r i p   " t e s t - $ i "   - - t c p   8 0   - o   j s o n   |   j q   - r   . s p e c . c l u s t e r I P ;   d o n e   1 0 . 9 6 . 0 . 1 1   1 0 . 9 6 . 0 . 5   1 0 . 9 6 . 0 . 1 2   1 0 . 9 6 . 0 . 1 3   1 0 . 9 6 . 0 . 1 4   1 0 . 9 6 . 0 . 2   1 0 . 9 6 . 0 . 3   1 0 . 9 6 . 0 . 4   1 0 . 9 6 . 0 . 6   1 0 . 9 6 . 0 . 7   1 0 . 9 6 . 0 . 8   1 0 . 9 6 . 0 . 9   e r r o r :   f a i l e d   t o   c r e a t e   C l u s t e r I P   s e r v i c e :   I n t e r n a l   e r r o r   o c c u r r e d :   f a i l e d   t o   a l l o c a t e   a   s e r v i c e I P :   r a n g e   i s   f u l l   Y o u   c a n   i n c r e a s e   t h e   n u m b e r   o f   I P   a d d r e s s e s   a v a i l a b l e   f o r   S e r v i c e s ,   b y   c r e a t i n g   a   n e w   S e r v i c e C I D R   t h a t   e x t e n d s   o r   a d d s   n e w   I P   a d d r e s s   r a n g e s .   c a t   < E O F   |   k u b e c t l   a p p l y   - f   -   a p i V e r s i o n :   n e t w o r k i n g . k 8 s . i o / v 1 b e t a 1   k i n d :   S e r v i c e C I D R   m e t a d a t a :   n a m e :   n e w c i d r 1   s p e c :   c i d r s :   -   1 0 . 9 6 . 0 . 0 / 2 4   E O F   s e r v i c e c i d r . n e t w o r k i n g . k 8 s . i o / n e w c i d r 1   c r e a t e d   a n d   t h i s   w i l l   a l l o w   y o u   t o   c r e a t e   n e w   S e r v i c e s   w i t h   C l u s t e r I P s   t h a t   w i l l   b e   p i c k e d   f r o m   t


Question: What is Deleting a ServiceCIDR?

Answer: Y o u   c a n n o t   d e l e t e   a   S e r v i c e C I D R   i f   t h e r e   a r e   I P A d d r e s s e s   t h a t   d e p e n d   o n   t h e   S e r v i c e C I D R .   k u b e c t l   d e l e t e   s e r v i c e c i d r   n e w c i d r 1   s e r v i c e c i d r . n e t w o r k i n g . k 8 s . i o   " n e w c i d r 1 "   d e l e t e d   K u b e r n e t e s   u s e s   a   f i n a l i z e r   o n   t h e   S e r v i c e C I D R   t o   t r a c k   t h i s   d e p e n d e n t   r e l a t i o n s h i p .   k u b e c t l   g e t   s e r v i c e c i d r   n e w c i d r 1   - o   y a m l   a p i V e r s i o n :   n e t w o r k i n g . k 8 s . i o / v 1 b e t a 1   k i n d :   S e r v i c e C I D R   m e t a d a t a :   c r e a t i o n T i m e s t a m p :   " 2 0 2 3 - 1 0 - 1 2 T 1 5 : 1 1 : 0 7 Z "   d e l e t i o n G r a c e P e r i o d S e c o n d s :   0   d e l e t i o n T i m e s t a m p :   " 2 0 2 3 - 1 0 - 1 2 T 1 5 : 1 2 : 4 5 Z "   f i n a l i z e r s :   -   n e t w o r k i n g . k 8 s . i o / s e r v i c e - c i d r - f i n a l i z e r   n a m e :   n e w c i d r 1   r e s o u r c e V e r s i o n :   " 1 1 3 3 "   u i d :   5 f f d 8 a f e - c 7 8 f - 4 e 6 0 - a e 7 6 - c e c 4 4 8 a 8 a f 4 0   s p e c :   c i d r s :   -   1 0 . 9 6 . 0 . 0 / 2 4   s t a t u s :   c o n d i t i o n s :   -   l a s t T r a n s i t i o n T i m e :   " 2 0 2 3 - 1 0 - 1 2 T 1 5 : 1 2 : 4 5 Z "   m e s s a g e :   T h e r e   a r e   s t i l l   I P A d d r e s s e s   r e f e r e n c i n g   t h e   S e r v i c e C I D R ,   p l e a s e   r e m o v e   t h e m   o r   c r e a t e   a   n e w   S e r v i c e C I D R   r e a s o n :   O r p h a n I P A d d r e s s   s t a t u s :   " F a l s e "   t y p e :   R e a d y   B y   r e m o v i n g   t h e   S e r v i c e s   c o n t a i n i n g   t h e   I P   a d d r e s s e s   t h a t   a r e   b l o c k i n g   t h e   d e l e t i o n   o f   t h e   S e r v i c e C I D R   f o r   i   i n   $ ( s e q   1 3   1 6 ) ;


Question: What is Kubernetes Service CIDR Policies?

Answer: C l u s t e r   a d m i n i s t r a t o r s   c a n   i m p l e m e n t   p o l i c i e s   t o   c o n t r o l   t h e   c r e a t i o n   a n d   m o d i f i c a t i o n   o f   S e r v i c e C I D R   r e s o u r c e s   w i t h i n   t h e   c l u s t e r .   T h i s   a l l o w s   f o r   c e n t r a l i z e d   m a n a g e m e n t   o f   t h e   I P   a d d r e s s   r a n g e s   u s e d   f o r   S e r v i c e s   a n d   h e l p s   p r e v e n t   u n i n t e n d e d   o r   c o n f l i c t i n g   c o n f i g u r a t i o n s .   K u b e r n e t e s   p r o v i d e s   m e c h a n i s m s   l i k e   V a l i d a t i n g   A d m i s s i o n   P o l i c i e s   t o   e n f o r c e   t h e s e   r u l e s .


Question: What is Preventing Unauthorized ServiceCIDR Creation/Update using Validating Admission Policy?

Answer: T h e r e   c a n   b e   s i t u a t i o n s   t h a t   t h e   c l u s t e r   a d m i n i s t r a t o r s   w a n t   t o   r e s t r i c t   t h e   r a n g e s   t h a t   c a n   b e   a l l o w e d   o r   t o   c o m p l e t e l y   d e n y   a n y   c h a n g e s   t o   t h e   c l u s t e r   S e r v i c e   I P   r a n g e s .


Question: What is Note:?

Answer: T h e   d e f a u l t   " k u b e r n e t e s "   S e r v i c e C I D R   i s   c r e a t e d   b y   t h e   k u b e - a p i s e r v e r   t o   p r o v i d e   c o n s i s t e n c y   i n   t h e   c l u s t e r   a n d   i s   r e q u i r e d   f o r   t h e   c l u s t e r   t o   w o r k ,   s o   i t   a l w a y s   m u s t   b e   a l l o w e d .   Y o u   c a n   e n s u r e   y o u r   V a l i d a t i n g A d m i s s i o n P o l i c y   d o e s n ' t   r e s t r i c t   t h e   d e f a u l t   S e r v i c e C I D R   b y   a d d i n g   t h e   c l a u s e :   m a t c h C o n d i t i o n s :   -   n a m e :   ' e x c l u d e - d e f a u l t - s e r v i c e c i d r '   e x p r e s s i o n :   " o b j e c t . m e t a d a t a . n a m e   ! =   ' k u b e r n e t e s ' "   a s   i n   t h e   e x a m p l e s   b e l o w .


Question: What is Restrict Service CIDR ranges to some specific ranges?

Answer: T h e   f o l l o w i n g   i s   a n   e x a m p l e   o f   a   V a l i d a t i n g A d m i s s i o n P o l i c y   t h a t   o n l y   a l l o w s   S e r v i c e C I D R s   t o   b e   c r e a t e d   i f   t h e y   a r e   s u b r a n g e s   o f   t h e   g i v e n   a l l o w e d   r a n g e s .   ( S o   t h e   e x a m p l e   p o l i c y   w o u l d   a l l o w   a   S e r v i c e C I D R   w i t h   c i d r s :   [ ' 1 0 . 9 6 . 1 . 0 / 2 4 ' ]   o r   c i d r s :   [ ' 2 0 0 1 : d b 8 : 0 : 0 : f f f f : : / 8 0 ' ,   ' 1 0 . 9 6 . 0 . 0 / 2 0 ' ]   b u t   w o u l d   n o t   a l l o w   a   S e r v i c e C I D R   w i t h   c i d r s :   [ ' 1 7 2 . 2 0 . 0 . 0 / 1 6 ' ] . )   Y o u   c a n   c o p y   t h i s   p o l i c y   a n d   c h a n g e   t h e   v a l u e   o f   a l l o w e d   t o   s o m e t h i n g   a p p r o p r i a t e   f o r   y o u   c l u s t e r .   a p i V e r s i o n :   a d m i s s i o n r e g i s t r a t i o n . k 8 s . i o / v 1   k i n d :   V a l i d a t i n g A d m i s s i o n P o l i c y   m e t a d a t a :   n a m e :   " s e r v i c e c i d r s . d e f a u l t "   s p e c :   f a i l u r e P o l i c y :   F a i l   m a t c h C o n s t r a i n t s :   r e s o u r c e R u l e s :   -   a p i G r o u p s :   [ " n e t w o r k i n g . k 8 s . i o " ]   a p i V e r s i o n s :   [ " v 1 " , " v 1 b e t a 1 " ]   o p e r a t i o n s :   [ " C R E A T E " ,   " U P D A T E " ]   r e s o u r c e s :   [ " s e r v i c e c i d r s " ]   m a t c h C o n d i t i o n s :   -   n a m e :   ' e x c l u d e - d e f a u l t - s e r v i c e c i d r '   e x p r e s s i o n :   " o b j e c t . m e t a d a t a . n a m e   ! =   ' k u b e r n e t e s ' "   v a r i a b l e s :   -   n a m e :   a l l o w e d   e x p r e s s i o n :   " [ ' 1 0 . 9 6 . 0 . 0 / 1 6 ' , ' 2 0 0 1 : d b 8 : : / 6 4 ' ] "   v a l i d a t i o n s :   -   e x p r e s s i o n :   " o b j e c t . s p e c . c i d r s . a l l ( n e w C I D R ,   v a r i a b l e s . a


Question: What is Restrict any usage of the ServiceCIDR API?

Answer: T h e   f o l l o w i n g   e x a m p l e   d e m o n s t r a t e s   h o w   t o   u s e   a   V a l i d a t i n g A d m i s s i o n P o l i c y   a n d   i t s   b i n d i n g   t o   r e s t r i c t   t h e   c r e a t i o n   o f   a n y   n e w   S e r v i c e   C I D R   r a n g e s ,   e x c l u d i n g   t h e   d e f a u l t   " k u b e r n e t e s "   S e r v i c e C I D R :   a p i V e r s i o n :   a d m i s s i o n r e g i s t r a t i o n . k 8 s . i o / v 1   k i n d :   V a l i d a t i n g A d m i s s i o n P o l i c y   m e t a d a t a :   n a m e :   " s e r v i c e c i d r s . d e n y "   s p e c :   f a i l u r e P o l i c y :   F a i l   m a t c h C o n s t r a i n t s :   r e s o u r c e R u l e s :   -   a p i G r o u p s :   [ " n e t w o r k i n g . k 8 s . i o " ]   a p i V e r s i o n s :   [ " v 1 " , " v 1 b e t a 1 " ]   o p e r a t i o n s :   [ " C R E A T E " ,   " U P D A T E " ]   r e s o u r c e s :   [ " s e r v i c e c i d r s " ]   v a l i d a t i o n s :   -   e x p r e s s i o n :   " o b j e c t . m e t a d a t a . n a m e   = =   ' k u b e r n e t e s ' "   - - -   a p i V e r s i o n :   a d m i s s i o n r e g i s t r a t i o n . k 8 s . i o / v 1   k i n d :   V a l i d a t i n g A d m i s s i o n P o l i c y B i n d i n g   m e t a d a t a :   n a m e :   " s e r v i c e c i d r s - d e n y - b i n d i n g "   s p e c :   p o l i c y N a m e :   " s e r v i c e c i d r s . d e n y "   v a l i d a t i o n A c t i o n s :   [ D e n y , A u d i t ]


Question: What is kubectl create job?

Answer: kubectl create jobSynopsisCreate a job with the specified name.kubectl create job NAME --image=image [--from=cronjob/name] -- [COMMAND] [args...] Examples # Create a job kubectl create job my-job --image=busybox # Create a job with a command kubectl create job my-job --image=busybox -- date # Create a job from a cron job named "a-cronjob" kubectl create job test-job --from=cronjob/a-cronjob Options--allow-missing-template-keys Default: trueIf true, ignore any errors in templates when a field or map key is missing in the template. Only applies to golang and jsonpath output formats.--dry-run string[="unchanged"] Default: "none"Must be "none", "server", or "client". If client strategy, only print the object that would be sent, without sending it. If server strategy, submit server-side request without persisting the resource.--field-manager string Default: "kubectl-create"Name of the manager used to track field ownership.--from stringThe name of the resource to create a Job from (only cronjob is supported).-h, --helphelp for job--image stringImage name to run.-o, --output stringOutput format. One of: (json, yaml, name, go-template, go-template-file, template, templatefile, jsonpath, jsonpath-as-json, jsonpath-file).--save-configIf true, the configuration of current object will be saved in its annotation. Otherwise, the annotation will be unchanged. This flag is useful when you want to perform kubectl apply on this object in the future.--show-managed-fieldsIf true, keep the managedFields when printing objects in JSON or YAML format.--template stringTemplate string or path to template file to use when -o=go-template, -o=go-template-file. The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview].--validate string[="strict"] Default: "strict"Must be one of: strict (or true), warn, ignore (or false). "true" or "strict" will use a schema to validate the input and fail the request if invalid. It will perform server side validation if ServerSideFieldValidation is enabled on the api-server, but will fall back to less reliable client-side validation if not. "warn" will warn about unknown or duplicate fields without blocking the request if server-side field validation is enabled on the API server, and behave as "ignore" otherwise. "false" or "ignore" will not perform any schema validation, silently dropping any unknown or duplicate fields.Parent Options Inherited--as stringUsername to impersonate for the operation. User could be a regular user or a service account in a namespace.--as-group stringsGroup to impersonate for the operation, this flag can be repeated to specify multiple groups.--as-uid stringUID to impersonate for the operation.--cache-dir string Default: "$HOME/.kube/cache"Default cache directory--certificate-authority stringPath to a cert file for the certificate authority--client-certificate stringPath to a client certificate file for TLS--client-key stringPath to a client key file for TLS--cluster stringThe name


Question: How does kubectl create job work?

Answer: kubectl create jobSynopsisCreate a job with the specified name.kubectl create job NAME --image=image [--from=cronjob/name] -- [COMMAND] [args...] Examples # Create a job kubectl create job my-job --image=busybox # Create a job with a command kubectl create job my-job --image=busybox -- date # Create a job from a cron job named "a-cronjob" kubectl create job test-job --from=cronjob/a-cronjob Options--allow-missing-template-keys Default: trueIf true, ignore any errors in templates when a field or map key is missing in the template. Only applies to golang and jsonpath output formats.--dry-run string[="unchanged"] Default: "none"Must be "none", "server", or "client". If client strategy, only print the object that would be sent, without sending it. If server strategy, submit server-side request without persisting the resource.--field-manager string Default: "kubectl-create"Name of the manager used to track field ownership.--from stringThe name of the resource to create a Job from (only cronjob is supported).-h, --helphelp for job--image stringImage name to run.-o, --output stringOutput format. One of: (json, yaml, name, go-template, go-template-file, template, templatefile, jsonpath, jsonpath-as-json, jsonpath-file).--save-configIf true, the configuration of current object will be saved in its annotation. Otherwise, the annotation will be unchanged. This flag is useful when you want to perform kubectl apply on this object in the future.--show-managed-fieldsIf true, keep the managedFields when printing objects in JSON or YAML format.--template stringTemplate string or path to template file to use when -o=go-template, -o=go-template-file. The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview].--validate string[="strict"] Default: "strict"Must be one of: strict (or true), warn, ignore (or false). "true" or "strict" will use a schema to validate the input and fail the request if invalid. It will perform server side validation if ServerSideFieldValidation is enabled on the api-server, but will fall back to less reliable client-side validation if not. "warn" will warn about unknown or duplicate fields without blocking the request if server-side field validation is enabled on the API server, and behave as "ignore" otherwise. "false" or "ignore" will not perform any schema validation, silently dropping any unknown or duplicate fields.Parent Options Inherited--as stringUsername to impersonate for the operation. User could be a regular user or a service account in a namespace.--as-group stringsGroup to impersonate for the operation, this flag can be repeated to specify multiple groups.--as-uid stringUID to impersonate for the operation.--cache-dir string Default: "$HOME/.kube/cache"Default cache directory--certificate-authority stringPath to a cert file for the certificate authority--client-certificate stringPath to a client certificate file for TLS--client-key stringPath to a client key file for TLS--cluster stringThe name


Question: When would you use kubectl create job?

Answer: kubectl create jobSynopsisCreate a job with the specified name.kubectl create job NAME --image=image [--from=cronjob/name] -- [COMMAND] [args...] Examples # Create a job kubectl create job my-job --image=busybox # Create a job with a command kubectl create job my-job --image=busybox -- date # Create a job from a cron job named "a-cronjob" kubectl create job test-job --from=cronjob/a-cronjob Options--allow-missing-template-keys Default: trueIf true, ignore any errors in templates when a field or map key is missing in the template. Only applies to golang and jsonpath output formats.--dry-run string[="unchanged"] Default: "none"Must be "none", "server", or "client". If client strategy, only print the object that would be sent, without sending it. If server strategy, submit server-side request without persisting the resource.--field-manager string Default: "kubectl-create"Name of the manager used to track field ownership.--from stringThe name of the resource to create a Job from (only cronjob is supported).-h, --helphelp for job--image stringImage name to run.-o, --output stringOutput format. One of: (json, yaml, name, go-template, go-template-file, template, templatefile, jsonpath, jsonpath-as-json, jsonpath-file).--save-configIf true, the configuration of current object will be saved in its annotation. Otherwise, the annotation will be unchanged. This flag is useful when you want to perform kubectl apply on this object in the future.--show-managed-fieldsIf true, keep the managedFields when printing objects in JSON or YAML format.--template stringTemplate string or path to template file to use when -o=go-template, -o=go-template-file. The template format is golang templates [http://golang.org/pkg/text/template/#pkg-overview].--validate string[="strict"] Default: "strict"Must be one of: strict (or true), warn, ignore (or false). "true" or "strict" will use a schema to validate the input and fail the request if invalid. It will perform server side validation if ServerSideFieldValidation is enabled on the api-server, but will fall back to less reliable client-side validation if not. "warn" will warn about unknown or duplicate fields without blocking the request if server-side field validation is enabled on the API server, and behave as "ignore" otherwise. "false" or "ignore" will not perform any schema validation, silently dropping any unknown or duplicate fields.Parent Options Inherited--as stringUsername to impersonate for the operation. User could be a regular user or a service account in a namespace.--as-group stringsGroup to impersonate for the operation, this flag can be repeated to specify multiple groups.--as-uid stringUID to impersonate for the operation.--cache-dir string Default: "$HOME/.kube/cache"Default cache directory--certificate-authority stringPath to a cert file for the certificate authority--client-certificate stringPath to a client certificate file for TLS--client-key stringPath to a client key file for TLS--cluster stringThe name