Question: What is Parent Options Inherited?

Answer: U s e r n a m e   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n .   U s e r   c o u l d   b e   a   r e g u l a r   u s e r   o r   a   s e r v i c e   a c c o u n t   i n   a   n a m e s p a c e .   G r o u p   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n ,   t h i s   f l a g   c a n   b e   r e p e a t e d   t o   s p e c i f y   m u l t i p l e   g r o u p s .   U I D   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n .   D e f a u l t   c a c h e   d i r e c t o r y   P a t h   t o   a   c e r t   f i l e   f o r   t h e   c e r t i f i c a t e   a u t h o r i t y   P a t h   t o   a   c l i e n t   c e r t i f i c a t e   f i l e   f o r   T L S   P a t h   t o   a   c l i e n t   k e y   f i l e   f o r   T L S   T h e   n a m e   o f   t h e   k u b e c o n f i g   c l u s t e r   t o   u s e   T h e   n a m e   o f   t h e   k u b e c o n f i g   c o n t e x t   t o   u s e   I f   t r u e ,   o p t - o u t   o f   r e s p o n s e   c o m p r e s s i o n   f o r   a l l   r e q u e s t s   t o   t h e   s e r v e r   I f   t r u e ,   t h e   s e r v e r ' s   c e r t i f i c a t e   w i l l   n o t   b e   c h e c k e d   f o r   v a l i d i t y .   T h i s   w i l l   m a k e   y o u r   H T T P S   c o n n e c t i o n s   i n s e c u r e   P a t h   t o   t h e   k u b e c o n f i g   f i l e   t o   u s e   f o r   C L I   r e q u e s t s .   P a t h   t o   t h e   k u b e r c   f i l e   t o   u s e   f o r   p r e f e r e n c e s .   T h i s   c a n   b e   d i s a b l e d   b y   e x p o r t i n g   K U B E C T L _ K U B E R C = f a l s e   f e a t u r e   g a t e   o r   t u r n i n g   o f f   t h e   f e a t u r e   K U B E R C = o f f .   R e q u i r e   s e r v e r   v e r s i o n   t o   m a t c h   c l i e n t   v e r s i o n   I f   p r e s e n t ,   t h e   n a m e s p a c e   s c o p e   f o r   t h i s   C L I   r e q u e s t   P a s s w o r d   f o r   b a s i c   a u t h e n t i c a t


Question: What is See Also?

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


Question: What is kubectl auth?

Answer: kubectl authSynopsisInspect authorization.kubectl auth [flags] Options-h, --helphelp for authParent 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 of the kubeconfig cluster to use--context stringThe name of the kubeconfig context to use--disable-compressionIf true, opt-out of response compression for all requests to the server--insecure-skip-tls-verifyIf true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure--kubeconfig stringPath to the kubeconfig file to use for CLI requests.--kuberc stringPath to the kuberc file to use for preferences. This can be disabled by exporting KUBECTL_KUBERC=false feature gate or turning off the feature KUBERC=off.--match-server-versionRequire server version to match client version-n, --namespace stringIf present, the namespace scope for this CLI request--password stringPassword for basic authentication to the API server--profile string Default: "none"Name of profile to capture. One of (none|cpu|heap|goroutine|threadcreate|block|mutex)--profile-output string Default: "profile.pprof"Name of the file to write the profile to--request-timeout string Default: "0"The length of time to wait before giving up on a single server request. Non-zero values should contain a corresponding time unit (e.g. 1s, 2m, 3h). A value of zero means don't timeout requests.-s, --server stringThe address and port of the Kubernetes API server--storage-driver-buffer-duration duration Default: 1m0sWrites in the storage driver will be buffered for this duration, and committed to the non memory backends as a single transaction--storage-driver-db string Default: "cadvisor"database name--storage-driver-host string Default: "localhost:8086"database host:port--storage-driver-password string Default: "root"database password--storage-driver-secureuse secure connection with database--storage-driver-table string Default: "stats"table name--storage-driver-user string Default: "root"database username--tls-server-name stringServer name to use for server certificate validation. If it is not provided, the hostname used to contact the server is used--token stringBearer token for authentication to the API server--user stringThe name of the kubeconfig user to use--username stringUsername for basic authentication to the API server--version version[=true]--version, --version=raw prints version information and quits; --version=vX.Y.Z... sets the reported version--warnings-as-er


Question: How does kubectl auth work?

Answer: kubectl authSynopsisInspect authorization.kubectl auth [flags] Options-h, --helphelp for authParent 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 of the kubeconfig cluster to use--context stringThe name of the kubeconfig context to use--disable-compressionIf true, opt-out of response compression for all requests to the server--insecure-skip-tls-verifyIf true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure--kubeconfig stringPath to the kubeconfig file to use for CLI requests.--kuberc stringPath to the kuberc file to use for preferences. This can be disabled by exporting KUBECTL_KUBERC=false feature gate or turning off the feature KUBERC=off.--match-server-versionRequire server version to match client version-n, --namespace stringIf present, the namespace scope for this CLI request--password stringPassword for basic authentication to the API server--profile string Default: "none"Name of profile to capture. One of (none|cpu|heap|goroutine|threadcreate|block|mutex)--profile-output string Default: "profile.pprof"Name of the file to write the profile to--request-timeout string Default: "0"The length of time to wait before giving up on a single server request. Non-zero values should contain a corresponding time unit (e.g. 1s, 2m, 3h). A value of zero means don't timeout requests.-s, --server stringThe address and port of the Kubernetes API server--storage-driver-buffer-duration duration Default: 1m0sWrites in the storage driver will be buffered for this duration, and committed to the non memory backends as a single transaction--storage-driver-db string Default: "cadvisor"database name--storage-driver-host string Default: "localhost:8086"database host:port--storage-driver-password string Default: "root"database password--storage-driver-secureuse secure connection with database--storage-driver-table string Default: "stats"table name--storage-driver-user string Default: "root"database username--tls-server-name stringServer name to use for server certificate validation. If it is not provided, the hostname used to contact the server is used--token stringBearer token for authentication to the API server--user stringThe name of the kubeconfig user to use--username stringUsername for basic authentication to the API server--version version[=true]--version, --version=raw prints version information and quits; --version=vX.Y.Z... sets the reported version--warnings-as-er


Question: When would you use kubectl auth?

Answer: kubectl authSynopsisInspect authorization.kubectl auth [flags] Options-h, --helphelp for authParent 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 of the kubeconfig cluster to use--context stringThe name of the kubeconfig context to use--disable-compressionIf true, opt-out of response compression for all requests to the server--insecure-skip-tls-verifyIf true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure--kubeconfig stringPath to the kubeconfig file to use for CLI requests.--kuberc stringPath to the kuberc file to use for preferences. This can be disabled by exporting KUBECTL_KUBERC=false feature gate or turning off the feature KUBERC=off.--match-server-versionRequire server version to match client version-n, --namespace stringIf present, the namespace scope for this CLI request--password stringPassword for basic authentication to the API server--profile string Default: "none"Name of profile to capture. One of (none|cpu|heap|goroutine|threadcreate|block|mutex)--profile-output string Default: "profile.pprof"Name of the file to write the profile to--request-timeout string Default: "0"The length of time to wait before giving up on a single server request. Non-zero values should contain a corresponding time unit (e.g. 1s, 2m, 3h). A value of zero means don't timeout requests.-s, --server stringThe address and port of the Kubernetes API server--storage-driver-buffer-duration duration Default: 1m0sWrites in the storage driver will be buffered for this duration, and committed to the non memory backends as a single transaction--storage-driver-db string Default: "cadvisor"database name--storage-driver-host string Default: "localhost:8086"database host:port--storage-driver-password string Default: "root"database password--storage-driver-secureuse secure connection with database--storage-driver-table string Default: "stats"table name--storage-driver-user string Default: "root"database username--tls-server-name stringServer name to use for server certificate validation. If it is not provided, the hostname used to contact the server is used--token stringBearer token for authentication to the API server--user stringThe name of the kubeconfig user to use--username stringUsername for basic authentication to the API server--version version[=true]--version, --version=raw prints version information and quits; --version=vX.Y.Z... sets the reported version--warnings-as-er


Question: What are the benefits of kubectl auth?

Answer: kubectl authSynopsisInspect authorization.kubectl auth [flags] Options-h, --helphelp for authParent 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 of the kubeconfig cluster to use--context stringThe name of the kubeconfig context to use--disable-compressionIf true, opt-out of response compression for all requests to the server--insecure-skip-tls-verifyIf true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure--kubeconfig stringPath to the kubeconfig file to use for CLI requests.--kuberc stringPath to the kuberc file to use for preferences. This can be disabled by exporting KUBECTL_KUBERC=false feature gate or turning off the feature KUBERC=off.--match-server-versionRequire server version to match client version-n, --namespace stringIf present, the namespace scope for this CLI request--password stringPassword for basic authentication to the API server--profile string Default: "none"Name of profile to capture. One of (none|cpu|heap|goroutine|threadcreate|block|mutex)--profile-output string Default: "profile.pprof"Name of the file to write the profile to--request-timeout string Default: "0"The length of time to wait before giving up on a single server request. Non-zero values should contain a corresponding time unit (e.g. 1s, 2m, 3h). A value of zero means don't timeout requests.-s, --server stringThe address and port of the Kubernetes API server--storage-driver-buffer-duration duration Default: 1m0sWrites in the storage driver will be buffered for this duration, and committed to the non memory backends as a single transaction--storage-driver-db string Default: "cadvisor"database name--storage-driver-host string Default: "localhost:8086"database host:port--storage-driver-password string Default: "root"database password--storage-driver-secureuse secure connection with database--storage-driver-table string Default: "stats"table name--storage-driver-user string Default: "root"database username--tls-server-name stringServer name to use for server certificate validation. If it is not provided, the hostname used to contact the server is used--token stringBearer token for authentication to the API server--user stringThe name of the kubeconfig user to use--username stringUsername for basic authentication to the API server--version version[=true]--version, --version=raw prints version information and quits; --version=vX.Y.Z... sets the reported version--warnings-as-er


Question: What is Synopsis?

Answer: I n s p e c t   a u t h o r i z a t i o n .   k u b e c t l   a u t h   [ f l a g s ]


Question: What is Options?

Answer: h e l p   f o r   a u t h


Question: What is Parent Options Inherited?

Answer: U s e r n a m e   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n .   U s e r   c o u l d   b e   a   r e g u l a r   u s e r   o r   a   s e r v i c e   a c c o u n t   i n   a   n a m e s p a c e .   G r o u p   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n ,   t h i s   f l a g   c a n   b e   r e p e a t e d   t o   s p e c i f y   m u l t i p l e   g r o u p s .   U I D   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n .   D e f a u l t   c a c h e   d i r e c t o r y   P a t h   t o   a   c e r t   f i l e   f o r   t h e   c e r t i f i c a t e   a u t h o r i t y   P a t h   t o   a   c l i e n t   c e r t i f i c a t e   f i l e   f o r   T L S   P a t h   t o   a   c l i e n t   k e y   f i l e   f o r   T L S   T h e   n a m e   o f   t h e   k u b e c o n f i g   c l u s t e r   t o   u s e   T h e   n a m e   o f   t h e   k u b e c o n f i g   c o n t e x t   t o   u s e   I f   t r u e ,   o p t - o u t   o f   r e s p o n s e   c o m p r e s s i o n   f o r   a l l   r e q u e s t s   t o   t h e   s e r v e r   I f   t r u e ,   t h e   s e r v e r ' s   c e r t i f i c a t e   w i l l   n o t   b e   c h e c k e d   f o r   v a l i d i t y .   T h i s   w i l l   m a k e   y o u r   H T T P S   c o n n e c t i o n s   i n s e c u r e   P a t h   t o   t h e   k u b e c o n f i g   f i l e   t o   u s e   f o r   C L I   r e q u e s t s .   P a t h   t o   t h e   k u b e r c   f i l e   t o   u s e   f o r   p r e f e r e n c e s .   T h i s   c a n   b e   d i s a b l e d   b y   e x p o r t i n g   K U B E C T L _ K U B E R C = f a l s e   f e a t u r e   g a t e   o r   t u r n i n g   o f f   t h e   f e a t u r e   K U B E R C = o f f .   R e q u i r e   s e r v e r   v e r s i o n   t o   m a t c h   c l i e n t   v e r s i o n   I f   p r e s e n t ,   t h e   n a m e s p a c e   s c o p e   f o r   t h i s   C L I   r e q u e s t   P a s s w o r d   f o r   b a s i c   a u t h e n t i c a t


Question: What is See Also?

Answer: k u b e c t l   -   k u b e c t l   c o n t r o l s   t h e   K u b e r n e t e s   c l u s t e r   m a n a g e r k u b e c t l   a u t h   c a n - i   -   C h e c k   w h e t h e r   a n   a c t i o n   i s   a l l o w e d k u b e c t l   a u t h   r e c o n c i l e   -   R e c o n c i l e s   r u l e s   f o r   R B A C   r o l e ,   r o l e   b i n d i n g ,   c l u s t e r   r o l e ,   a n d   c l u s t e r   r o l e   b i n d i n g   o b j e c t s k u b e c t l   a u t h   w h o a m i   -   E x p e r i m e n t a l :   C h e c k   s e l f   s u b j e c t   a t t r i b u t e s   T h i s   p a g e   i s   a u t o m a t i c a l l y   g e n e r a t e d .   I f   y o u   p l a n   t o   r e p o r t   a n   i s s u e   w i t h   t h i s   p a g e ,   m e n t i o n   t h a t   t h e   p a g e   i s   a u t o - g e n e r a t e d   i n   y o u r   i s s u e   d e s c r i p t i o n .   T h e   f i x   m a y   n e e d   t o   h a p p e n   e l s e w h e r e   i n   t h e   K u b e r n e t e s   p r o j e c t .


Question: What is Change the default StorageClass?

Answer: Change the default StorageClassThis page shows how to change the default Storage Class that is used to provision volumes for PersistentVolumeClaims that have no special requirements.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.Why change the default storage class?Depending on the installation method, your Kubernetes cluster may be deployed with an existing StorageClass that is marked as default. This default StorageClass is then used to dynamically provision storage for PersistentVolumeClaims that do not require any specific storage class. See PersistentVolumeClaim documentation for details.The pre-installed default StorageClass may not fit well with your expected workload; for example, it might provision storage that is too expensive. If this is the case, you can either change the default StorageClass or disable it completely to avoid dynamic provisioning of storage.Deleting the default StorageClass may not work, as it may be re-created automatically by the addon manager running in your cluster. Please consult the docs for your installation for details about addon manager and how to disable individual addons.Changing the default StorageClassList the StorageClasses in your cluster:kubectl get storageclass The output is similar to this:NAME PROVISIONER AGE standard (default) kubernetes.io/gce-pd 1d gold kubernetes.io/gce-pd 1d The default StorageClass is marked by (default).Mark the default StorageClass as non-default:The default StorageClass has an annotation storageclass.kubernetes.io/is-default-class set to true. Any other value or absence of the annotation is interpreted as false.To mark a StorageClass as non-default, you need to change its value to false:kubectl patch storageclass standard -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"false"}}}' where standard is the name of your chosen StorageClass.Mark a StorageClass as default:Similar to the previous step, you need to add/set the annotation storageclass.kubernetes.io/is-default-class=true.kubectl patch storageclass gold -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}' Please note you can have multiple StorageClass marked as default. If more than one StorageClass is marked as default, a PersistentVolumeClaim without an explicitly defined storageClassName will be created using the most recently created default StorageClass. When a PersistentVolumeClaim is created with a specified volumeName, it remains in a pending state if the static volume's storageClassName does not match the StorageCl


Question: How does Change the default StorageClass work?

Answer: Change the default StorageClassThis page shows how to change the default Storage Class that is used to provision volumes for PersistentVolumeClaims that have no special requirements.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.Why change the default storage class?Depending on the installation method, your Kubernetes cluster may be deployed with an existing StorageClass that is marked as default. This default StorageClass is then used to dynamically provision storage for PersistentVolumeClaims that do not require any specific storage class. See PersistentVolumeClaim documentation for details.The pre-installed default StorageClass may not fit well with your expected workload; for example, it might provision storage that is too expensive. If this is the case, you can either change the default StorageClass or disable it completely to avoid dynamic provisioning of storage.Deleting the default StorageClass may not work, as it may be re-created automatically by the addon manager running in your cluster. Please consult the docs for your installation for details about addon manager and how to disable individual addons.Changing the default StorageClassList the StorageClasses in your cluster:kubectl get storageclass The output is similar to this:NAME PROVISIONER AGE standard (default) kubernetes.io/gce-pd 1d gold kubernetes.io/gce-pd 1d The default StorageClass is marked by (default).Mark the default StorageClass as non-default:The default StorageClass has an annotation storageclass.kubernetes.io/is-default-class set to true. Any other value or absence of the annotation is interpreted as false.To mark a StorageClass as non-default, you need to change its value to false:kubectl patch storageclass standard -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"false"}}}' where standard is the name of your chosen StorageClass.Mark a StorageClass as default:Similar to the previous step, you need to add/set the annotation storageclass.kubernetes.io/is-default-class=true.kubectl patch storageclass gold -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}' Please note you can have multiple StorageClass marked as default. If more than one StorageClass is marked as default, a PersistentVolumeClaim without an explicitly defined storageClassName will be created using the most recently created default StorageClass. When a PersistentVolumeClaim is created with a specified volumeName, it remains in a pending state if the static volume's storageClassName does not match the StorageCl


Question: When would you use Change the default StorageClass?

Answer: Change the default StorageClassThis page shows how to change the default Storage Class that is used to provision volumes for PersistentVolumeClaims that have no special requirements.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.Why change the default storage class?Depending on the installation method, your Kubernetes cluster may be deployed with an existing StorageClass that is marked as default. This default StorageClass is then used to dynamically provision storage for PersistentVolumeClaims that do not require any specific storage class. See PersistentVolumeClaim documentation for details.The pre-installed default StorageClass may not fit well with your expected workload; for example, it might provision storage that is too expensive. If this is the case, you can either change the default StorageClass or disable it completely to avoid dynamic provisioning of storage.Deleting the default StorageClass may not work, as it may be re-created automatically by the addon manager running in your cluster. Please consult the docs for your installation for details about addon manager and how to disable individual addons.Changing the default StorageClassList the StorageClasses in your cluster:kubectl get storageclass The output is similar to this:NAME PROVISIONER AGE standard (default) kubernetes.io/gce-pd 1d gold kubernetes.io/gce-pd 1d The default StorageClass is marked by (default).Mark the default StorageClass as non-default:The default StorageClass has an annotation storageclass.kubernetes.io/is-default-class set to true. Any other value or absence of the annotation is interpreted as false.To mark a StorageClass as non-default, you need to change its value to false:kubectl patch storageclass standard -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"false"}}}' where standard is the name of your chosen StorageClass.Mark a StorageClass as default:Similar to the previous step, you need to add/set the annotation storageclass.kubernetes.io/is-default-class=true.kubectl patch storageclass gold -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}' Please note you can have multiple StorageClass marked as default. If more than one StorageClass is marked as default, a PersistentVolumeClaim without an explicitly defined storageClassName will be created using the most recently created default StorageClass. When a PersistentVolumeClaim is created with a specified volumeName, it remains in a pending state if the static volume's storageClassName does not match the StorageCl


Question: What are the benefits of Change the default StorageClass?

Answer: Change the default StorageClassThis page shows how to change the default Storage Class that is used to provision volumes for PersistentVolumeClaims that have no special requirements.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.Why change the default storage class?Depending on the installation method, your Kubernetes cluster may be deployed with an existing StorageClass that is marked as default. This default StorageClass is then used to dynamically provision storage for PersistentVolumeClaims that do not require any specific storage class. See PersistentVolumeClaim documentation for details.The pre-installed default StorageClass may not fit well with your expected workload; for example, it might provision storage that is too expensive. If this is the case, you can either change the default StorageClass or disable it completely to avoid dynamic provisioning of storage.Deleting the default StorageClass may not work, as it may be re-created automatically by the addon manager running in your cluster. Please consult the docs for your installation for details about addon manager and how to disable individual addons.Changing the default StorageClassList the StorageClasses in your cluster:kubectl get storageclass The output is similar to this:NAME PROVISIONER AGE standard (default) kubernetes.io/gce-pd 1d gold kubernetes.io/gce-pd 1d The default StorageClass is marked by (default).Mark the default StorageClass as non-default:The default StorageClass has an annotation storageclass.kubernetes.io/is-default-class set to true. Any other value or absence of the annotation is interpreted as false.To mark a StorageClass as non-default, you need to change its value to false:kubectl patch storageclass standard -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"false"}}}' where standard is the name of your chosen StorageClass.Mark a StorageClass as default:Similar to the previous step, you need to add/set the annotation storageclass.kubernetes.io/is-default-class=true.kubectl patch storageclass gold -p '{"metadata": {"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}' Please note you can have multiple StorageClass marked as default. If more than one StorageClass is marked as default, a PersistentVolumeClaim without an explicitly defined storageClassName will be created using the most recently created default StorageClass. When a PersistentVolumeClaim is created with a specified volumeName, it remains in a pending state if the static volume's storageClassName does not match the StorageCl


Question: What is Change the default StorageClass?

Answer: T h i s   p a g e   s h o w s   h o w   t o   c h a n g e   t h e   d e f a u l t   S t o r a g e   C l a s s   t h a t   i s   u s e d   t o   p r o v i s i o n   v o l u m e s   f o r   P e r s i s t e n t V o l u m e C l a i m s   t h a t   h a v e   n o   s p e c i a l   r e q u i r e m e n t s .


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 Why change the default storage class??

Answer: D e p e n d i n g   o n   t h e   i n s t a l l a t i o n   m e t h o d ,   y o u r   K u b e r n e t e s   c l u s t e r   m a y   b e   d e p l o y e d   w i t h   a n   e x i s t i n g   S t o r a g e C l a s s   t h a t   i s   m a r k e d   a s   d e f a u l t .   T h i s   d e f a u l t   S t o r a g e C l a s s   i s   t h e n   u s e d   t o   d y n a m i c a l l y   p r o v i s i o n   s t o r a g e   f o r   P e r s i s t e n t V o l u m e C l a i m s   t h a t   d o   n o t   r e q u i r e   a n y   s p e c i f i c   s t o r a g e   c l a s s .   S e e   P e r s i s t e n t V o l u m e C l a i m   d o c u m e n t a t i o n   f o r   d e t a i l s .   T h e   p r e - i n s t a l l e d   d e f a u l t   S t o r a g e C l a s s   m a y   n o t   f i t   w e l l   w i t h   y o u r   e x p e c t e d   w o r k l o a d ;   f o r   e x a m p l e ,   i t   m i g h t   p r o v i s i o n   s t o r a g e   t h a t   i s   t o o   e x p e n s i v e .   I f   t h i s   i s   t h e   c a s e ,   y o u   c a n   e i t h e r   c h a n g e   t h e   d e f a u l t   S t o r a g e C l a s s   o r   d i s a b l e   i t   c o m p l e t e l y   t o   a v o i d   d y n a m i c   p r o v i s i o n i n g   o f   s t o r a g e .   D e l e t i n g   t h e   d e f a u l t   S t o r a g e C l a s s   m a y   n o t   w o r k ,   a s   i t   m a y   b e   r e - c r e a t e d   a u t o m a t i c a l l y   b y   t h e   a d d o n   m a n a g e r   r u n n i n g   i n   y o u r   c l u s t e r .   P l e a s e   c o n s u l t   t h e   d o c s   f o r   y o u r   i n s t a l l a t i o n   f o r   d e t a i l s   a b o u t   a d d o n   m a n a g e r   a n d   h o w   t o   d i s a b l e   i n d i v i d u a l   a d d o n s .


Question: What is Changing the default StorageClass?

Answer: L i s t   t h e   S t o r a g e C l a s s e s   i n   y o u r   c l u s t e r : k u b e c t l   g e t   s t o r a g e c l a s s   T h e   o u t p u t   i s   s i m i l a r   t o   t h i s : N A M E   P R O V I S I O N E R   A G E   s t a n d a r d   ( d e f a u l t )   k u b e r n e t e s . i o / g c e - p d   1 d   g o l d   k u b e r n e t e s . i o / g c e - p d   1 d   T h e   d e f a u l t   S t o r a g e C l a s s   i s   m a r k e d   b y   ( d e f a u l t ) . M a r k   t h e   d e f a u l t   S t o r a g e C l a s s   a s   n o n - d e f a u l t : T h e   d e f a u l t   S t o r a g e C l a s s   h a s   a n   a n n o t a t i o n   s t o r a g e c l a s s . k u b e r n e t e s . i o / i s - d e f a u l t - c l a s s   s e t   t o   t r u e .   A n y   o t h e r   v a l u e   o r   a b s e n c e   o f   t h e   a n n o t a t i o n   i s   i n t e r p r e t e d   a s   f a l s e . T o   m a r k   a   S t o r a g e C l a s s   a s   n o n - d e f a u l t ,   y o u   n e e d   t o   c h a n g e   i t s   v a l u e   t o   f a l s e : k u b e c t l   p a t c h   s t o r a g e c l a s s   s t a n d a r d   - p   ' { " m e t a d a t a " :   { " a n n o t a t i o n s " : { " s t o r a g e c l a s s . k u b e r n e t e s . i o / i s - d e f a u l t - c l a s s " : " f a l s e " } } } '   w h e r e   s t a n d a r d   i s   t h e   n a m e   o f   y o u r   c h o s e n   S t o r a g e C l a s s . M a r k   a   S t o r a g e C l a s s   a s   d e f a u l t : S i m i l a r   t o   t h e   p r e v i o u s   s t e p ,   y o u   n e e d   t o   a d d / s e t   t h e   a n n o t a t i o n   s t o r a g e c l a s s . k u b e r n e t e s . i o / i s - d e f a u l t - c l a s s = t r u e . k u b e c t l   p a t c h   s t o r a g e c l a s s   g o l d   - p   ' { " m e t a d a t a " :   { " a n n o t a t i o n s " : { " s t o r a g e c l a s s . k u b e r n e t e s . i o / i s - d e f a u l t - c l a s s " : " t r u e " } } } '   P l e a s e   n o t e   y o u   c a n   h a v e


Question: What is What's next?

Answer: L e a r n   m o r e   a b o u t   P e r s i s t e n t V o l u m e s .


Question: What is kubectl create quota?

Answer: kubectl create quotaSynopsisCreate a resource quota with the specified name, hard limits, and optional scopes.kubectl create quota NAME [--hard=key1=value1,key2=value2] [--scopes=Scope1,Scope2] [--dry-run=server|client|none] Examples # Create a new resource quota named my-quota kubectl create quota my-quota --hard=cpu=1,memory=1G,pods=2,services=3,replicationcontrollers=2,resourcequotas=1,secrets=5,persistentvolumeclaims=10 # Create a new resource quota named best-effort kubectl create quota best-effort --hard=pods=100 --scopes=BestEffort 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.--hard stringA comma-delimited set of resource=quantity pairs that define a hard limit.-h, --helphelp for quota-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.--scopes stringA comma-delimited set of quota scopes that must all match each object tracked by the quota.--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 direct


Question: How does kubectl create quota work?

Answer: kubectl create quotaSynopsisCreate a resource quota with the specified name, hard limits, and optional scopes.kubectl create quota NAME [--hard=key1=value1,key2=value2] [--scopes=Scope1,Scope2] [--dry-run=server|client|none] Examples # Create a new resource quota named my-quota kubectl create quota my-quota --hard=cpu=1,memory=1G,pods=2,services=3,replicationcontrollers=2,resourcequotas=1,secrets=5,persistentvolumeclaims=10 # Create a new resource quota named best-effort kubectl create quota best-effort --hard=pods=100 --scopes=BestEffort 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.--hard stringA comma-delimited set of resource=quantity pairs that define a hard limit.-h, --helphelp for quota-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.--scopes stringA comma-delimited set of quota scopes that must all match each object tracked by the quota.--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 direct


Question: When would you use kubectl create quota?

Answer: kubectl create quotaSynopsisCreate a resource quota with the specified name, hard limits, and optional scopes.kubectl create quota NAME [--hard=key1=value1,key2=value2] [--scopes=Scope1,Scope2] [--dry-run=server|client|none] Examples # Create a new resource quota named my-quota kubectl create quota my-quota --hard=cpu=1,memory=1G,pods=2,services=3,replicationcontrollers=2,resourcequotas=1,secrets=5,persistentvolumeclaims=10 # Create a new resource quota named best-effort kubectl create quota best-effort --hard=pods=100 --scopes=BestEffort 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.--hard stringA comma-delimited set of resource=quantity pairs that define a hard limit.-h, --helphelp for quota-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.--scopes stringA comma-delimited set of quota scopes that must all match each object tracked by the quota.--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 direct


Question: What are the benefits of kubectl create quota?

Answer: kubectl create quotaSynopsisCreate a resource quota with the specified name, hard limits, and optional scopes.kubectl create quota NAME [--hard=key1=value1,key2=value2] [--scopes=Scope1,Scope2] [--dry-run=server|client|none] Examples # Create a new resource quota named my-quota kubectl create quota my-quota --hard=cpu=1,memory=1G,pods=2,services=3,replicationcontrollers=2,resourcequotas=1,secrets=5,persistentvolumeclaims=10 # Create a new resource quota named best-effort kubectl create quota best-effort --hard=pods=100 --scopes=BestEffort 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.--hard stringA comma-delimited set of resource=quantity pairs that define a hard limit.-h, --helphelp for quota-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.--scopes stringA comma-delimited set of quota scopes that must all match each object tracked by the quota.--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 direct


Question: What is Synopsis?

Answer: C r e a t e   a   r e s o u r c e   q u o t a   w i t h   t h e   s p e c i f i e d   n a m e ,   h a r d   l i m i t s ,   a n d   o p t i o n a l   s c o p e s .   k u b e c t l   c r e a t e   q u o t a   N A M E   [ - - h a r d = k e y 1 = v a l u e 1 , k e y 2 = v a l u e 2 ]   [ - - s c o p e s = S c o p e 1 , S c o p e 2 ]   [ - - d r y - r u n = s e r v e r | c l i e n t | n o n e ]


Question: What is Examples?

Answer: #   C r e a t e   a   n e w   r e s o u r c e   q u o t a   n a m e d   m y - q u o t a   k u b e c t l   c r e a t e   q u o t a   m y - q u o t a   - - h a r d = c p u = 1 , m e m o r y = 1 G , p o d s = 2 , s e r v i c e s = 3 , r e p l i c a t i o n c o n t r o l l e r s = 2 , r e s o u r c e q u o t a s = 1 , s e c r e t s = 5 , p e r s i s t e n t v o l u m e c l a i m s = 1 0   #   C r e a t e   a   n e w   r e s o u r c e   q u o t a   n a m e d   b e s t - e f f o r t   k u b e c t l   c r e a t e   q u o t a   b e s t - e f f o r t   - - h a r d = p o d s = 1 0 0   - - s c o p e s = B e s t E f f o r t


Question: What is Options?

Answer: I f   t r u e ,   i g n o r e   a n y   e r r o r s   i n   t e m p l a t e s   w h e n   a   f i e l d   o r   m a p   k e y   i s   m i s s i n g   i n   t h e   t e m p l a t e .   O n l y   a p p l i e s   t o   g o l a n g   a n d   j s o n p a t h   o u t p u t   f o r m a t s .   M u s t   b e   " n o n e " ,   " s e r v e r " ,   o r   " c l i e n t " .   I f   c l i e n t   s t r a t e g y ,   o n l y   p r i n t   t h e   o b j e c t   t h a t   w o u l d   b e   s e n t ,   w i t h o u t   s e n d i n g   i t .   I f   s e r v e r   s t r a t e g y ,   s u b m i t   s e r v e r - s i d e   r e q u e s t   w i t h o u t   p e r s i s t i n g   t h e   r e s o u r c e .   N a m e   o f   t h e   m a n a g e r   u s e d   t o   t r a c k   f i e l d   o w n e r s h i p .   A   c o m m a - d e l i m i t e d   s e t   o f   r e s o u r c e = q u a n t i t y   p a i r s   t h a t   d e f i n e   a   h a r d   l i m i t .   h e l p   f o r   q u o t a   O u t p u t   f o r m a t .   O n e   o f :   ( j s o n ,   y a m l ,   n a m e ,   g o - t e m p l a t e ,   g o - t e m p l a t e - f i l e ,   t e m p l a t e ,   t e m p l a t e f i l e ,   j s o n p a t h ,   j s o n p a t h - a s - j s o n ,   j s o n p a t h - f i l e ) .   I f   t r u e ,   t h e   c o n f i g u r a t i o n   o f   c u r r e n t   o b j e c t   w i l l   b e   s a v e d   i n   i t s   a n n o t a t i o n .   O t h e r w i s e ,   t h e   a n n o t a t i o n   w i l l   b e   u n c h a n g e d .   T h i s   f l a g   i s   u s e f u l   w h e n   y o u   w a n t   t o   p e r f o r m   k u b e c t l   a p p l y   o n   t h i s   o b j e c t   i n   t h e   f u t u r e .   A   c o m m a - d e l i m i t e d   s e t   o f   q u o t a   s c o p e s   t h a t   m u s t   a l l   m a t c h   e a c h   o b j e c t   t r a c k e d   b y   t h e   q u o t a .   I f   t r u e ,   k e e p   t h e   m a n a g e d F i e l d s   w h e n   p r i n t i n g   o b j e c t s   i n   J S O N   o r   Y A M L


Question: What is Parent Options Inherited?

Answer: U s e r n a m e   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n .   U s e r   c o u l d   b e   a   r e g u l a r   u s e r   o r   a   s e r v i c e   a c c o u n t   i n   a   n a m e s p a c e .   G r o u p   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n ,   t h i s   f l a g   c a n   b e   r e p e a t e d   t o   s p e c i f y   m u l t i p l e   g r o u p s .   U I D   t o   i m p e r s o n a t e   f o r   t h e   o p e r a t i o n .   D e f a u l t   c a c h e   d i r e c t o r y   P a t h   t o   a   c e r t   f i l e   f o r   t h e   c e r t i f i c a t e   a u t h o r i t y   P a t h   t o   a   c l i e n t   c e r t i f i c a t e   f i l e   f o r   T L S   P a t h   t o   a   c l i e n t   k e y   f i l e   f o r   T L S   T h e   n a m e   o f   t h e   k u b e c o n f i g   c l u s t e r   t o   u s e   T h e   n a m e   o f   t h e   k u b e c o n f i g   c o n t e x t   t o   u s e   I f   t r u e ,   o p t - o u t   o f   r e s p o n s e   c o m p r e s s i o n   f o r   a l l   r e q u e s t s   t o   t h e   s e r v e r   I f   t r u e ,   t h e   s e r v e r ' s   c e r t i f i c a t e   w i l l   n o t   b e   c h e c k e d   f o r   v a l i d i t y .   T h i s   w i l l   m a k e   y o u r   H T T P S   c o n n e c t i o n s   i n s e c u r e   P a t h   t o   t h e   k u b e c o n f i g   f i l e   t o   u s e   f o r   C L I   r e q u e s t s .   P a t h   t o   t h e   k u b e r c   f i l e   t o   u s e   f o r   p r e f e r e n c e s .   T h i s   c a n   b e   d i s a b l e d   b y   e x p o r t i n g   K U B E C T L _ K U B E R C = f a l s e   f e a t u r e   g a t e   o r   t u r n i n g   o f f   t h e   f e a t u r e   K U B E R C = o f f .   R e q u i r e   s e r v e r   v e r s i o n   t o   m a t c h   c l i e n t   v e r s i o n   I f   p r e s e n t ,   t h e   n a m e s p a c e   s c o p e   f o r   t h i s   C L I   r e q u e s t   P a s s w o r d   f o r   b a s i c   a u t h e n t i c a t


Question: What is See Also?

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


Question: What is Ephemeral Containers?

Answer: Ephemeral ContainersFEATURE STATE: Kubernetes v1.25 [stable]This page provides an overview of ephemeral containers: a special type of container that runs temporarily in an existing Pod to accomplish user-initiated actions such as troubleshooting. You use ephemeral containers to inspect services rather than to build applications.Understanding ephemeral containersPods are the fundamental building block of Kubernetes applications. Since Pods are intended to be disposable and replaceable, you cannot add a container to a Pod once it has been created. Instead, you usually delete and replace Pods in a controlled fashion using deployments.Sometimes it's necessary to inspect the state of an existing Pod, however, for example to troubleshoot a hard-to-reproduce bug. In these cases you can run an ephemeral container in an existing Pod to inspect its state and run arbitrary commands.What is an ephemeral container?Ephemeral containers differ from other containers in that they lack guarantees for resources or execution, and they will never be automatically restarted, so they are not appropriate for building applications. Ephemeral containers are described using the same ContainerSpec as regular containers, but many fields are incompatible and disallowed for ephemeral containers.Ephemeral containers may not have ports, so fields such as ports, livenessProbe, readinessProbe are disallowed.Pod resource allocations are immutable, so setting resources is disallowed.For a complete list of allowed fields, see the EphemeralContainer reference documentation.Ephemeral containers are created using a special ephemeralcontainers handler in the API rather than by adding them directly to pod.spec, so it's not possible to add an ephemeral container using kubectl edit.Like regular containers, you may not change or remove an ephemeral container after you have added it to a Pod.Note:Ephemeral containers are not supported by static pods.Uses for ephemeral containersEphemeral containers are useful for interactive troubleshooting when kubectl exec is insufficient because a container has crashed or a container image doesn't include debugging utilities.In particular, distroless images enable you to deploy minimal container images that reduce attack surface and exposure to bugs and vulnerabilities. Since distroless images do not include a shell or any debugging utilities, it's difficult to troubleshoot distroless images using kubectl exec alone.When using ephemeral containers, it's helpful to enable process namespace sharing so you can view processes in other containers.What's nextLearn how to debug pods using ephemeral containers.


Question: How does Ephemeral Containers work?

Answer: Ephemeral ContainersFEATURE STATE: Kubernetes v1.25 [stable]This page provides an overview of ephemeral containers: a special type of container that runs temporarily in an existing Pod to accomplish user-initiated actions such as troubleshooting. You use ephemeral containers to inspect services rather than to build applications.Understanding ephemeral containersPods are the fundamental building block of Kubernetes applications. Since Pods are intended to be disposable and replaceable, you cannot add a container to a Pod once it has been created. Instead, you usually delete and replace Pods in a controlled fashion using deployments.Sometimes it's necessary to inspect the state of an existing Pod, however, for example to troubleshoot a hard-to-reproduce bug. In these cases you can run an ephemeral container in an existing Pod to inspect its state and run arbitrary commands.What is an ephemeral container?Ephemeral containers differ from other containers in that they lack guarantees for resources or execution, and they will never be automatically restarted, so they are not appropriate for building applications. Ephemeral containers are described using the same ContainerSpec as regular containers, but many fields are incompatible and disallowed for ephemeral containers.Ephemeral containers may not have ports, so fields such as ports, livenessProbe, readinessProbe are disallowed.Pod resource allocations are immutable, so setting resources is disallowed.For a complete list of allowed fields, see the EphemeralContainer reference documentation.Ephemeral containers are created using a special ephemeralcontainers handler in the API rather than by adding them directly to pod.spec, so it's not possible to add an ephemeral container using kubectl edit.Like regular containers, you may not change or remove an ephemeral container after you have added it to a Pod.Note:Ephemeral containers are not supported by static pods.Uses for ephemeral containersEphemeral containers are useful for interactive troubleshooting when kubectl exec is insufficient because a container has crashed or a container image doesn't include debugging utilities.In particular, distroless images enable you to deploy minimal container images that reduce attack surface and exposure to bugs and vulnerabilities. Since distroless images do not include a shell or any debugging utilities, it's difficult to troubleshoot distroless images using kubectl exec alone.When using ephemeral containers, it's helpful to enable process namespace sharing so you can view processes in other containers.What's nextLearn how to debug pods using ephemeral containers.


Question: When would you use Ephemeral Containers?

Answer: Ephemeral ContainersFEATURE STATE: Kubernetes v1.25 [stable]This page provides an overview of ephemeral containers: a special type of container that runs temporarily in an existing Pod to accomplish user-initiated actions such as troubleshooting. You use ephemeral containers to inspect services rather than to build applications.Understanding ephemeral containersPods are the fundamental building block of Kubernetes applications. Since Pods are intended to be disposable and replaceable, you cannot add a container to a Pod once it has been created. Instead, you usually delete and replace Pods in a controlled fashion using deployments.Sometimes it's necessary to inspect the state of an existing Pod, however, for example to troubleshoot a hard-to-reproduce bug. In these cases you can run an ephemeral container in an existing Pod to inspect its state and run arbitrary commands.What is an ephemeral container?Ephemeral containers differ from other containers in that they lack guarantees for resources or execution, and they will never be automatically restarted, so they are not appropriate for building applications. Ephemeral containers are described using the same ContainerSpec as regular containers, but many fields are incompatible and disallowed for ephemeral containers.Ephemeral containers may not have ports, so fields such as ports, livenessProbe, readinessProbe are disallowed.Pod resource allocations are immutable, so setting resources is disallowed.For a complete list of allowed fields, see the EphemeralContainer reference documentation.Ephemeral containers are created using a special ephemeralcontainers handler in the API rather than by adding them directly to pod.spec, so it's not possible to add an ephemeral container using kubectl edit.Like regular containers, you may not change or remove an ephemeral container after you have added it to a Pod.Note:Ephemeral containers are not supported by static pods.Uses for ephemeral containersEphemeral containers are useful for interactive troubleshooting when kubectl exec is insufficient because a container has crashed or a container image doesn't include debugging utilities.In particular, distroless images enable you to deploy minimal container images that reduce attack surface and exposure to bugs and vulnerabilities. Since distroless images do not include a shell or any debugging utilities, it's difficult to troubleshoot distroless images using kubectl exec alone.When using ephemeral containers, it's helpful to enable process namespace sharing so you can view processes in other containers.What's nextLearn how to debug pods using ephemeral containers.


Question: What are the benefits of Ephemeral Containers?

Answer: Ephemeral ContainersFEATURE STATE: Kubernetes v1.25 [stable]This page provides an overview of ephemeral containers: a special type of container that runs temporarily in an existing Pod to accomplish user-initiated actions such as troubleshooting. You use ephemeral containers to inspect services rather than to build applications.Understanding ephemeral containersPods are the fundamental building block of Kubernetes applications. Since Pods are intended to be disposable and replaceable, you cannot add a container to a Pod once it has been created. Instead, you usually delete and replace Pods in a controlled fashion using deployments.Sometimes it's necessary to inspect the state of an existing Pod, however, for example to troubleshoot a hard-to-reproduce bug. In these cases you can run an ephemeral container in an existing Pod to inspect its state and run arbitrary commands.What is an ephemeral container?Ephemeral containers differ from other containers in that they lack guarantees for resources or execution, and they will never be automatically restarted, so they are not appropriate for building applications. Ephemeral containers are described using the same ContainerSpec as regular containers, but many fields are incompatible and disallowed for ephemeral containers.Ephemeral containers may not have ports, so fields such as ports, livenessProbe, readinessProbe are disallowed.Pod resource allocations are immutable, so setting resources is disallowed.For a complete list of allowed fields, see the EphemeralContainer reference documentation.Ephemeral containers are created using a special ephemeralcontainers handler in the API rather than by adding them directly to pod.spec, so it's not possible to add an ephemeral container using kubectl edit.Like regular containers, you may not change or remove an ephemeral container after you have added it to a Pod.Note:Ephemeral containers are not supported by static pods.Uses for ephemeral containersEphemeral containers are useful for interactive troubleshooting when kubectl exec is insufficient because a container has crashed or a container image doesn't include debugging utilities.In particular, distroless images enable you to deploy minimal container images that reduce attack surface and exposure to bugs and vulnerabilities. Since distroless images do not include a shell or any debugging utilities, it's difficult to troubleshoot distroless images using kubectl exec alone.When using ephemeral containers, it's helpful to enable process namespace sharing so you can view processes in other containers.What's nextLearn how to debug pods using ephemeral containers.


Question: What is Ephemeral Containers?

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


Question: What is Understanding ephemeral containers?

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


Question: What is What is an ephemeral container??

Answer: E p h e m e r a l   c o n t a i n e r s   d i f f e r   f r o m   o t h e r   c o n t a i n e r s   i n   t h a t   t h e y   l a c k   g u a r a n t e e s   f o r   r e s o u r c e s   o r   e x e c u t i o n ,   a n d   t h e y   w i l l   n e v e r   b e   a u t o m a t i c a l l y   r e s t a r t e d ,   s o   t h e y   a r e   n o t   a p p r o p r i a t e   f o r   b u i l d i n g   a p p l i c a t i o n s .   E p h e m e r a l   c o n t a i n e r s   a r e   d e s c r i b e d   u s i n g   t h e   s a m e   C o n t a i n e r S p e c   a s   r e g u l a r   c o n t a i n e r s ,   b u t   m a n y   f i e l d s   a r e   i n c o m p a t i b l e   a n d   d i s a l l o w e d   f o r   e p h e m e r a l   c o n t a i n e r s .   E p h e m e r a l   c o n t a i n e r s   m a y   n o t   h a v e   p o r t s ,   s o   f i e l d s   s u c h   a s   p o r t s ,   l i v e n e s s P r o b e ,   r e a d i n e s s P r o b e   a r e   d i s a l l o w e d . P o d   r e s o u r c e   a l l o c a t i o n s   a r e   i m m u t a b l e ,   s o   s e t t i n g   r e s o u r c e s   i s   d i s a l l o w e d . F o r   a   c o m p l e t e   l i s t   o f   a l l o w e d   f i e l d s ,   s e e   t h e   E p h e m e r a l C o n t a i n e r   r e f e r e n c e   d o c u m e n t a t i o n .   E p h e m e r a l   c o n t a i n e r s   a r e   c r e a t e d   u s i n g   a   s p e c i a l   e p h e m e r a l c o n t a i n e r s   h a n d l e r   i n   t h e   A P I   r a t h e r   t h a n   b y   a d d i n g   t h e m   d i r e c t l y   t o   p o d . s p e c ,   s o   i t ' s   n o t   p o s s i b l e   t o   a d d   a n   e p h e m e r a l   c o n t a i n e r   u s i n g   k u b e c t l   e d i t .   L i k e   r e g u l a r   c o n t a i n e r s ,   y o u   m a y   n o t   c h a n g e   o r   r e m o v e   a n   e p h e m e r a l   c o n t a i n e r   a f t e r   y o u   h a v e   a d d e d   i t   t o   a   P o d .


Question: What is Uses for ephemeral containers?

Answer: E p h e m e r a l   c o n t a i n e r s   a r e   u s e f u l   f o r   i n t e r a c t i v e   t r o u b l e s h o o t i n g   w h e n   k u b e c t l   e x e c   i s   i n s u f f i c i e n t   b e c a u s e   a   c o n t a i n e r   h a s   c r a s h e d   o r   a   c o n t a i n e r   i m a g e   d o e s n ' t   i n c l u d e   d e b u g g i n g   u t i l i t i e s .   I n   p a r t i c u l a r ,   d i s t r o l e s s   i m a g e s   e n a b l e   y o u   t o   d e p l o y   m i n i m a l   c o n t a i n e r   i m a g e s   t h a t   r e d u c e   a t t a c k   s u r f a c e   a n d   e x p o s u r e   t o   b u g s   a n d   v u l n e r a b i l i t i e s .   S i n c e   d i s t r o l e s s   i m a g e s   d o   n o t   i n c l u d e   a   s h e l l   o r   a n y   d e b u g g i n g   u t i l i t i e s ,   i t ' s   d i f f i c u l t   t o   t r o u b l e s h o o t   d i s t r o l e s s   i m a g e s   u s i n g   k u b e c t l   e x e c   a l o n e .   W h e n   u s i n g   e p h e m e r a l   c o n t a i n e r s ,   i t ' s   h e l p f u l   t o   e n a b l e   p r o c e s s   n a m e s p a c e   s h a r i n g   s o   y o u   c a n   v i e w   p r o c e s s e s   i n   o t h e r   c o n t a i n e r s .


Question: What is What's next?

Answer: L e a r n   h o w   t o   d e b u g   p o d s   u s i n g   e p h e m e r a l   c o n t a i n e r s .


Question: What is Pod Scheduling Readiness?

Answer: Pod Scheduling ReadinessFEATURE STATE: Kubernetes v1.30 [stable]Pods were considered ready for scheduling once created. Kubernetes scheduler does its due diligence to find nodes to place all pending Pods. However, in a real-world case, some Pods may stay in a "miss-essential-resources" state for a long period. These Pods actually churn the scheduler (and downstream integrators like Cluster AutoScaler) in an unnecessary manner.By specifying/removing a Pod's .spec.schedulingGates, you can control when a Pod is ready to be considered for scheduling.Configuring Pod schedulingGatesThe schedulingGates field contains a list of strings, and each string literal is perceived as a criteria that Pod should be satisfied before considered schedulable. This field can be initialized only when a Pod is created (either by the client, or mutated during admission). After creation, each schedulingGate can be removed in arbitrary order, but addition of a new scheduling gate is disallowed.Figure. Pod SchedulingGatesUsage exampleTo mark a Pod not-ready for scheduling, you can create it with one or more scheduling gates like this:pods/pod-with-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: schedulingGates: - name: example.com/foo - name: example.com/bar containers: - name: pause image: registry.k8s.io/pause:3.6 After the Pod's creation, you can check its state using:kubectl get pod test-pod The output reveals it's in SchedulingGated state:NAME READY STATUS RESTARTS AGE test-pod 0/1 SchedulingGated 0 7s You can also check its schedulingGates field by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is:[{"name":"example.com/foo"},{"name":"example.com/bar"}] To inform scheduler this Pod is ready for scheduling, you can remove its schedulingGates entirely by reapplying a modified manifest:pods/pod-without-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: containers: - name: pause image: registry.k8s.io/pause:3.6 You can check if the schedulingGates is cleared by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is expected to be empty. And you can check its latest status by running:kubectl get pod test-pod -o wide Given the test-pod doesn't request any CPU/memory resources, it's expected that this Pod's state get transited from previous SchedulingGated to Running:NAME READY STATUS RESTARTS AGE IP NODE test-pod 1/1 Running 0 15s 10.0.0.4 node-2 ObservabilityThe metric scheduler_pending_pods comes with a new label "gated" to distinguish whether a Pod has been tried scheduling but claimed as unschedulable, or explicitly marked as not ready for scheduling. You can use scheduler_pending_pods{queue="gated"} to check the metric result.Mutable Pod scheduling directivesYou can mutate scheduling directives of Pods while they have scheduling gates, with certain constraints. At a high level, you can only tighten the scheduling directives of a Pod. In other words, t


Question: How does Pod Scheduling Readiness work?

Answer: Pod Scheduling ReadinessFEATURE STATE: Kubernetes v1.30 [stable]Pods were considered ready for scheduling once created. Kubernetes scheduler does its due diligence to find nodes to place all pending Pods. However, in a real-world case, some Pods may stay in a "miss-essential-resources" state for a long period. These Pods actually churn the scheduler (and downstream integrators like Cluster AutoScaler) in an unnecessary manner.By specifying/removing a Pod's .spec.schedulingGates, you can control when a Pod is ready to be considered for scheduling.Configuring Pod schedulingGatesThe schedulingGates field contains a list of strings, and each string literal is perceived as a criteria that Pod should be satisfied before considered schedulable. This field can be initialized only when a Pod is created (either by the client, or mutated during admission). After creation, each schedulingGate can be removed in arbitrary order, but addition of a new scheduling gate is disallowed.Figure. Pod SchedulingGatesUsage exampleTo mark a Pod not-ready for scheduling, you can create it with one or more scheduling gates like this:pods/pod-with-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: schedulingGates: - name: example.com/foo - name: example.com/bar containers: - name: pause image: registry.k8s.io/pause:3.6 After the Pod's creation, you can check its state using:kubectl get pod test-pod The output reveals it's in SchedulingGated state:NAME READY STATUS RESTARTS AGE test-pod 0/1 SchedulingGated 0 7s You can also check its schedulingGates field by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is:[{"name":"example.com/foo"},{"name":"example.com/bar"}] To inform scheduler this Pod is ready for scheduling, you can remove its schedulingGates entirely by reapplying a modified manifest:pods/pod-without-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: containers: - name: pause image: registry.k8s.io/pause:3.6 You can check if the schedulingGates is cleared by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is expected to be empty. And you can check its latest status by running:kubectl get pod test-pod -o wide Given the test-pod doesn't request any CPU/memory resources, it's expected that this Pod's state get transited from previous SchedulingGated to Running:NAME READY STATUS RESTARTS AGE IP NODE test-pod 1/1 Running 0 15s 10.0.0.4 node-2 ObservabilityThe metric scheduler_pending_pods comes with a new label "gated" to distinguish whether a Pod has been tried scheduling but claimed as unschedulable, or explicitly marked as not ready for scheduling. You can use scheduler_pending_pods{queue="gated"} to check the metric result.Mutable Pod scheduling directivesYou can mutate scheduling directives of Pods while they have scheduling gates, with certain constraints. At a high level, you can only tighten the scheduling directives of a Pod. In other words, t


Question: When would you use Pod Scheduling Readiness?

Answer: Pod Scheduling ReadinessFEATURE STATE: Kubernetes v1.30 [stable]Pods were considered ready for scheduling once created. Kubernetes scheduler does its due diligence to find nodes to place all pending Pods. However, in a real-world case, some Pods may stay in a "miss-essential-resources" state for a long period. These Pods actually churn the scheduler (and downstream integrators like Cluster AutoScaler) in an unnecessary manner.By specifying/removing a Pod's .spec.schedulingGates, you can control when a Pod is ready to be considered for scheduling.Configuring Pod schedulingGatesThe schedulingGates field contains a list of strings, and each string literal is perceived as a criteria that Pod should be satisfied before considered schedulable. This field can be initialized only when a Pod is created (either by the client, or mutated during admission). After creation, each schedulingGate can be removed in arbitrary order, but addition of a new scheduling gate is disallowed.Figure. Pod SchedulingGatesUsage exampleTo mark a Pod not-ready for scheduling, you can create it with one or more scheduling gates like this:pods/pod-with-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: schedulingGates: - name: example.com/foo - name: example.com/bar containers: - name: pause image: registry.k8s.io/pause:3.6 After the Pod's creation, you can check its state using:kubectl get pod test-pod The output reveals it's in SchedulingGated state:NAME READY STATUS RESTARTS AGE test-pod 0/1 SchedulingGated 0 7s You can also check its schedulingGates field by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is:[{"name":"example.com/foo"},{"name":"example.com/bar"}] To inform scheduler this Pod is ready for scheduling, you can remove its schedulingGates entirely by reapplying a modified manifest:pods/pod-without-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: containers: - name: pause image: registry.k8s.io/pause:3.6 You can check if the schedulingGates is cleared by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is expected to be empty. And you can check its latest status by running:kubectl get pod test-pod -o wide Given the test-pod doesn't request any CPU/memory resources, it's expected that this Pod's state get transited from previous SchedulingGated to Running:NAME READY STATUS RESTARTS AGE IP NODE test-pod 1/1 Running 0 15s 10.0.0.4 node-2 ObservabilityThe metric scheduler_pending_pods comes with a new label "gated" to distinguish whether a Pod has been tried scheduling but claimed as unschedulable, or explicitly marked as not ready for scheduling. You can use scheduler_pending_pods{queue="gated"} to check the metric result.Mutable Pod scheduling directivesYou can mutate scheduling directives of Pods while they have scheduling gates, with certain constraints. At a high level, you can only tighten the scheduling directives of a Pod. In other words, t


Question: What are the benefits of Pod Scheduling Readiness?

Answer: Pod Scheduling ReadinessFEATURE STATE: Kubernetes v1.30 [stable]Pods were considered ready for scheduling once created. Kubernetes scheduler does its due diligence to find nodes to place all pending Pods. However, in a real-world case, some Pods may stay in a "miss-essential-resources" state for a long period. These Pods actually churn the scheduler (and downstream integrators like Cluster AutoScaler) in an unnecessary manner.By specifying/removing a Pod's .spec.schedulingGates, you can control when a Pod is ready to be considered for scheduling.Configuring Pod schedulingGatesThe schedulingGates field contains a list of strings, and each string literal is perceived as a criteria that Pod should be satisfied before considered schedulable. This field can be initialized only when a Pod is created (either by the client, or mutated during admission). After creation, each schedulingGate can be removed in arbitrary order, but addition of a new scheduling gate is disallowed.Figure. Pod SchedulingGatesUsage exampleTo mark a Pod not-ready for scheduling, you can create it with one or more scheduling gates like this:pods/pod-with-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: schedulingGates: - name: example.com/foo - name: example.com/bar containers: - name: pause image: registry.k8s.io/pause:3.6 After the Pod's creation, you can check its state using:kubectl get pod test-pod The output reveals it's in SchedulingGated state:NAME READY STATUS RESTARTS AGE test-pod 0/1 SchedulingGated 0 7s You can also check its schedulingGates field by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is:[{"name":"example.com/foo"},{"name":"example.com/bar"}] To inform scheduler this Pod is ready for scheduling, you can remove its schedulingGates entirely by reapplying a modified manifest:pods/pod-without-scheduling-gates.yaml apiVersion: v1 kind: Pod metadata: name: test-pod spec: containers: - name: pause image: registry.k8s.io/pause:3.6 You can check if the schedulingGates is cleared by running:kubectl get pod test-pod -o jsonpath='{.spec.schedulingGates}' The output is expected to be empty. And you can check its latest status by running:kubectl get pod test-pod -o wide Given the test-pod doesn't request any CPU/memory resources, it's expected that this Pod's state get transited from previous SchedulingGated to Running:NAME READY STATUS RESTARTS AGE IP NODE test-pod 1/1 Running 0 15s 10.0.0.4 node-2 ObservabilityThe metric scheduler_pending_pods comes with a new label "gated" to distinguish whether a Pod has been tried scheduling but claimed as unschedulable, or explicitly marked as not ready for scheduling. You can use scheduler_pending_pods{queue="gated"} to check the metric result.Mutable Pod scheduling directivesYou can mutate scheduling directives of Pods while they have scheduling gates, with certain constraints. At a high level, you can only tighten the scheduling directives of a Pod. In other words, t


Question: What is Pod Scheduling Readiness?

Answer: P o d s   w e r e   c o n s i d e r e d   r e a d y   f o r   s c h e d u l i n g   o n c e   c r e a t e d .   K u b e r n e t e s   s c h e d u l e r   d o e s   i t s   d u e   d i l i g e n c e   t o   f i n d   n o d e s   t o   p l a c e   a l l   p e n d i n g   P o d s .   H o w e v e r ,   i n   a   r e a l - w o r l d   c a s e ,   s o m e   P o d s   m a y   s t a y   i n   a   " m i s s - e s s e n t i a l - r e s o u r c e s "   s t a t e   f o r   a   l o n g   p e r i o d .   T h e s e   P o d s   a c t u a l l y   c h u r n   t h e   s c h e d u l e r   ( a n d   d o w n s t r e a m   i n t e g r a t o r s   l i k e   C l u s t e r   A u t o S c a l e r )   i n   a n   u n n e c e s s a r y   m a n n e r .   B y   s p e c i f y i n g / r e m o v i n g   a   P o d ' s   . s p e c . s c h e d u l i n g G a t e s ,   y o u   c a n   c o n t r o l   w h e n   a   P o d   i s   r e a d y   t o   b e   c o n s i d e r e d   f o r   s c h e d u l i n g .


Question: What is Configuring Pod schedulingGates?

Answer: T h e   s c h e d u l i n g G a t e s   f i e l d   c o n t a i n s   a   l i s t   o f   s t r i n g s ,   a n d   e a c h   s t r i n g   l i t e r a l   i s   p e r c e i v e d   a s   a   c r i t e r i a   t h a t   P o d   s h o u l d   b e   s a t i s f i e d   b e f o r e   c o n s i d e r e d   s c h e d u l a b l e .   T h i s   f i e l d   c a n   b e   i n i t i a l i z e d   o n l y   w h e n   a   P o d   i s   c r e a t e d   ( e i t h e r   b y   t h e   c l i e n t ,   o r   m u t a t e d   d u r i n g   a d m i s s i o n ) .   A f t e r   c r e a t i o n ,   e a c h   s c h e d u l i n g G a t e   c a n   b e   r e m o v e d   i n   a r b i t r a r y   o r d e r ,   b u t   a d d i t i o n   o f   a   n e w   s c h e d u l i n g   g a t e   i s   d i s a l l o w e d .   F i g u r e .   P o d   S c h e d u l i n g G a t e s


Question: What is Usage example?

Answer: T o   m a r k   a   P o d   n o t - r e a d y   f o r   s c h e d u l i n g ,   y o u   c a n   c r e a t e   i t   w i t h   o n e   o r   m o r e   s c h e d u l i n g   g a t e s   l i k e   t h i 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 :   t e s t - p o d   s p e c :   s c h e d u l i n g G a t e s :   -   n a m e :   e x a m p l e . c o m / f o o   -   n a m e :   e x a m p l e . c o m / b a r   c o n t a i n e r s :   -   n a m e :   p a u s e   i m a g e :   r e g i s t r y . k 8 s . i o / p a u s e : 3 . 6   A f t e r   t h e   P o d ' s   c r e a t i o n ,   y o u   c a n   c h e c k   i t s   s t a t e   u s i n g :   k u b e c t l   g e t   p o d   t e s t - p o d   T h e   o u t p u t   r e v e a l s   i t ' s   i n   S c h e d u l i n g G a t e d   s t a t e :   N A M E   R E A D Y   S T A T U S   R E S T A R T S   A G E   t e s t - p o d   0 / 1   S c h e d u l i n g G a t e d   0   7 s   Y o u   c a n   a l s o   c h e c k   i t s   s c h e d u l i n g G a t e s   f i e l d   b y   r u n n i n g :   k u b e c t l   g e t   p o d   t e s t - p o d   - o   j s o n p a t h = ' { . s p e c . s c h e d u l i n g G a t e s } '   T h e   o u t p u t   i s :   [ { " n a m e " : " e x a m p l e . c o m / f o o " } , { " n a m e " : " e x a m p l e . c o m / b a r " } ]   T o   i n f o r m   s c h e d u l e r   t h i s   P o d   i s   r e a d y   f o r   s c h e d u l i n g ,   y o u   c a n   r e m o v e   i t s   s c h e d u l i n g G a t e s   e n t i r e l y   b y   r e a p p l y i n g   a   m o d i f i e d   m a n i f e s t :   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 :   t e s t - p o d   s p e c :   c o n t a i n e r s :   -   n a m e :   p a u s e   i m a g e :   r e g i s t r y . k 8 s . i o / p a u s e : 3 . 6   Y o u   c a n   c h e c k   i f   t h e   s c h e d u l i n g G a t e s   i s   c l e a r e d   b y   r u n n i n g :   k u b e c t l   g e t   p o d   t e s t -


Question: What is Observability?

Answer: T h e   m e t r i c   s c h e d u l e r _ p e n d i n g _ p o d s   c o m e s   w i t h   a   n e w   l a b e l   " g a t e d "   t o   d i s t i n g u i s h   w h e t h e r   a   P o d   h a s   b e e n   t r i e d   s c h e d u l i n g   b u t   c l a i m e d   a s   u n s c h e d u l a b l e ,   o r   e x p l i c i t l y   m a r k e d   a s   n o t   r e a d y   f o r   s c h e d u l i n g .   Y o u   c a n   u s e   s c h e d u l e r _ p e n d i n g _ p o d s { q u e u e = " g a t e d " }   t o   c h e c k   t h e   m e t r i c   r e s u l t .


Question: What is Mutable Pod scheduling directives?

Answer: Y o u   c a n   m u t a t e   s c h e d u l i n g   d i r e c t i v e s   o f   P o d s   w h i l e   t h e y   h a v e   s c h e d u l i n g   g a t e s ,   w i t h   c e r t a i n   c o n s t r a i n t s .   A t   a   h i g h   l e v e l ,   y o u   c a n   o n l y   t i g h t e n   t h e   s c h e d u l i n g   d i r e c t i v e s   o f   a   P o d .   I n   o t h e r   w o r d s ,   t h e   u p d a t e d   d i r e c t i v e s   w o u l d   c a u s e   t h e   P o d s   t o   o n l y   b e   a b l e   t o   b e   s c h e d u l e d   o n   a   s u b s e t   o f   t h e   n o d e s   t h a t   i t   w o u l d   p r e v i o u s l y   m a t c h .   M o r e   c o n c r e t e l y ,   t h e   r u l e s   f o r   u p d a t i n g   a   P o d ' s   s c h e d u l i n g   d i r e c t i v e s   a r e   a s   f o l l o w s :   F o r   . s p e c . n o d e S e l e c t o r ,   o n l y   a d d i t i o n s   a r e   a l l o w e d .   I f   a b s e n t ,   i t   w i l l   b e   a l l o w e d   t o   b e   s e t . F o r   s p e c . a f f i n i t y . n o d e A f f i n i t y ,   i f   n i l ,   t h e n   s e t t i n g   a n y t h i n g   i s   a l l o w e d . I f   N o d e S e l e c t o r T e r m s   w a s   e m p t y ,   i t   w i l l   b e   a l l o w e d   t o   b e   s e t .   I f   n o t   e m p t y ,   t h e n   o n l y   a d d i t i o n s   o f   N o d e S e l e c t o r R e q u i r e m e n t s   t o   m a t c h E x p r e s s i o n s   o r   f i e l d E x p r e s s i o n s   a r e   a l l o w e d ,   a n d   n o   c h a n g e s   t o   e x i s t i n g   m a t c h E x p r e s s i o n s   a n d   f i e l d E x p r e s s i o n s   w i l l   b e   a l l o w e d .   T h i s   i s   b e c a u s e   t h e   t e r m s   i n   . r e q u i r e d D u r i n g S c h e d u l i n g I g n o r e d D u r i n g E x e c u t i o n . N o d e S e l e c t o r T e r m s ,   a r e   O R e d   w h i l e   t h e   e x p r e s s i o n s   i n   n o d e S e l e c t o r T e r m s [ ] . m a t c h E x p r e s s


Question: What is What's next?

Answer: R e a d   t h e   P o d S c h e d u l i n g R e a d i n e s s   K E P   f o r   m o r e   d e t a i l s


Question: What is CSIStorageCapacity?

Answer: CSIStorageCapacityCSIStorageCapacity stores the result of one CSI GetCapacity call.apiVersion: storage.k8s.io/v1import "k8s.io/api/storage/v1"CSIStorageCapacityCSIStorageCapacity stores the result of one CSI GetCapacity call. For a given StorageClass, this describes the available capacity in a particular topology segment. This can be used when considering where to instantiate new PersistentVolumes.For example this can express things like: - StorageClass "standard" has "1234 GiB" available in "topology.kubernetes.io/zone=us-east1" - StorageClass "localssd" has "10 GiB" available in "kubernetes.io/hostname=knode-abc123"The following three cases all imply that no capacity is available for a certain combination: - no object exists with suitable topology and storage class name - such an object exists, but the capacity is unset - such an object exists, but the capacity is zeroThe producer of these objects can decide which approach is more suitable.They are consumed by the kube-scheduler when a CSI driver opts into capacity-aware scheduling with CSIDriverSpec.StorageCapacity. The scheduler compares the MaximumVolumeSize against the requested size of pending volumes to filter out unsuitable nodes. If MaximumVolumeSize is unset, it falls back to a comparison against the less precise Capacity. If that is also unset, the scheduler assumes that capacity is insufficient and tries some other node.apiVersion: storage.k8s.io/v1kind: CSIStorageCapacitymetadata (ObjectMeta)Standard object's metadata. The name has no particular meaning. It must be a DNS subdomain (dots allowed, 253 characters). To ensure that there are no conflicts with other CSI drivers on the cluster, the recommendation is to use csisc-<uuid>, a generated name, or a reverse-domain name which ends with the unique CSI driver name.Objects are namespaced.More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadatastorageClassName (string), requiredstorageClassName represents the name of the StorageClass that the reported capacity applies to. It must meet the same requirements as the name of a StorageClass object (non-empty, DNS subdomain). If that object no longer exists, the CSIStorageCapacity object is obsolete and should be removed by its creator. This field is immutable.capacity (Quantity)capacity is the value reported by the CSI driver in its GetCapacityResponse for a GetCapacityRequest with topology and parameters that match the previous fields.The semantic is currently (CSI spec 1.2) defined as: The available capacity, in bytes, of the storage that can be used to provision volumes. If not set, that information is currently unavailable.maximumVolumeSize (Quantity)maximumVolumeSize is the value reported by the CSI driver in its GetCapacityResponse for a GetCapacityRequest with topology and parameters that match the previous fields.This is defined since CSI spec 1.4.0 as the largest size that may be used in a CreateVolumeRequest.capacity_range.required_b


Question: How does CSIStorageCapacity work?

Answer: CSIStorageCapacityCSIStorageCapacity stores the result of one CSI GetCapacity call.apiVersion: storage.k8s.io/v1import "k8s.io/api/storage/v1"CSIStorageCapacityCSIStorageCapacity stores the result of one CSI GetCapacity call. For a given StorageClass, this describes the available capacity in a particular topology segment. This can be used when considering where to instantiate new PersistentVolumes.For example this can express things like: - StorageClass "standard" has "1234 GiB" available in "topology.kubernetes.io/zone=us-east1" - StorageClass "localssd" has "10 GiB" available in "kubernetes.io/hostname=knode-abc123"The following three cases all imply that no capacity is available for a certain combination: - no object exists with suitable topology and storage class name - such an object exists, but the capacity is unset - such an object exists, but the capacity is zeroThe producer of these objects can decide which approach is more suitable.They are consumed by the kube-scheduler when a CSI driver opts into capacity-aware scheduling with CSIDriverSpec.StorageCapacity. The scheduler compares the MaximumVolumeSize against the requested size of pending volumes to filter out unsuitable nodes. If MaximumVolumeSize is unset, it falls back to a comparison against the less precise Capacity. If that is also unset, the scheduler assumes that capacity is insufficient and tries some other node.apiVersion: storage.k8s.io/v1kind: CSIStorageCapacitymetadata (ObjectMeta)Standard object's metadata. The name has no particular meaning. It must be a DNS subdomain (dots allowed, 253 characters). To ensure that there are no conflicts with other CSI drivers on the cluster, the recommendation is to use csisc-<uuid>, a generated name, or a reverse-domain name which ends with the unique CSI driver name.Objects are namespaced.More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadatastorageClassName (string), requiredstorageClassName represents the name of the StorageClass that the reported capacity applies to. It must meet the same requirements as the name of a StorageClass object (non-empty, DNS subdomain). If that object no longer exists, the CSIStorageCapacity object is obsolete and should be removed by its creator. This field is immutable.capacity (Quantity)capacity is the value reported by the CSI driver in its GetCapacityResponse for a GetCapacityRequest with topology and parameters that match the previous fields.The semantic is currently (CSI spec 1.2) defined as: The available capacity, in bytes, of the storage that can be used to provision volumes. If not set, that information is currently unavailable.maximumVolumeSize (Quantity)maximumVolumeSize is the value reported by the CSI driver in its GetCapacityResponse for a GetCapacityRequest with topology and parameters that match the previous fields.This is defined since CSI spec 1.4.0 as the largest size that may be used in a CreateVolumeRequest.capacity_range.required_b


Question: When would you use CSIStorageCapacity?

Answer: CSIStorageCapacityCSIStorageCapacity stores the result of one CSI GetCapacity call.apiVersion: storage.k8s.io/v1import "k8s.io/api/storage/v1"CSIStorageCapacityCSIStorageCapacity stores the result of one CSI GetCapacity call. For a given StorageClass, this describes the available capacity in a particular topology segment. This can be used when considering where to instantiate new PersistentVolumes.For example this can express things like: - StorageClass "standard" has "1234 GiB" available in "topology.kubernetes.io/zone=us-east1" - StorageClass "localssd" has "10 GiB" available in "kubernetes.io/hostname=knode-abc123"The following three cases all imply that no capacity is available for a certain combination: - no object exists with suitable topology and storage class name - such an object exists, but the capacity is unset - such an object exists, but the capacity is zeroThe producer of these objects can decide which approach is more suitable.They are consumed by the kube-scheduler when a CSI driver opts into capacity-aware scheduling with CSIDriverSpec.StorageCapacity. The scheduler compares the MaximumVolumeSize against the requested size of pending volumes to filter out unsuitable nodes. If MaximumVolumeSize is unset, it falls back to a comparison against the less precise Capacity. If that is also unset, the scheduler assumes that capacity is insufficient and tries some other node.apiVersion: storage.k8s.io/v1kind: CSIStorageCapacitymetadata (ObjectMeta)Standard object's metadata. The name has no particular meaning. It must be a DNS subdomain (dots allowed, 253 characters). To ensure that there are no conflicts with other CSI drivers on the cluster, the recommendation is to use csisc-<uuid>, a generated name, or a reverse-domain name which ends with the unique CSI driver name.Objects are namespaced.More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadatastorageClassName (string), requiredstorageClassName represents the name of the StorageClass that the reported capacity applies to. It must meet the same requirements as the name of a StorageClass object (non-empty, DNS subdomain). If that object no longer exists, the CSIStorageCapacity object is obsolete and should be removed by its creator. This field is immutable.capacity (Quantity)capacity is the value reported by the CSI driver in its GetCapacityResponse for a GetCapacityRequest with topology and parameters that match the previous fields.The semantic is currently (CSI spec 1.2) defined as: The available capacity, in bytes, of the storage that can be used to provision volumes. If not set, that information is currently unavailable.maximumVolumeSize (Quantity)maximumVolumeSize is the value reported by the CSI driver in its GetCapacityResponse for a GetCapacityRequest with topology and parameters that match the previous fields.This is defined since CSI spec 1.4.0 as the largest size that may be used in a CreateVolumeRequest.capacity_range.required_b