Question: What is Debug Init Containers?

Answer: Debug Init ContainersThis page shows how to investigate problems related to the execution of Init Containers. The example command lines below refer to the Pod as <pod-name> and the Init Containers as <init-container-1> and <init-container-2>.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.You should be familiar with the basics of Init Containers.You should have Configured an Init Container.Checking the status of Init ContainersDisplay the status of your pod:kubectl get pod <pod-name> For example, a status of Init:1/2 indicates that one of two Init Containers has completed successfully:NAME READY STATUS RESTARTS AGE <pod-name> 0/1 Init:1/2 0 7s See Understanding Pod status for more examples of status values and their meanings.Getting details about Init ContainersView more detailed information about Init Container execution:kubectl describe pod <pod-name> For example, a Pod with two Init Containers might show the following:Init Containers: <init-container-1>: Container ID: ... ... State: Terminated Reason: Completed Exit Code: 0 Started: ... Finished: ... Ready: True Restart Count: 0 ... <init-container-2>: Container ID: ... ... State: Waiting Reason: CrashLoopBackOff Last State: Terminated Reason: Error Exit Code: 1 Started: ... Finished: ... Ready: False Restart Count: 3 ... You can also access the Init Container statuses programmatically by reading the status.initContainerStatuses field on the Pod Spec:kubectl get pod nginx --template '{{.status.initContainerStatuses}}' This command will return the same information as above in raw JSON.Accessing logs from Init ContainersPass the Init Container name along with the Pod name to access its logs.kubectl logs <pod-name> -c <init-container-2> Init Containers that run a shell script print commands as they're executed. For example, you can do this in Bash by running set -x at the beginning of the script.Understanding Pod statusA Pod status beginning with Init: summarizes the status of Init Container execution. The table below describes some example status values that you might see while debugging Init Containers.StatusMeaningInit:N/MThe Pod has M Init Containers, and N have completed so far.Init:ErrorAn Init Container has failed to execute.Init:CrashLoopBackOffAn Init Container has failed repeatedly.PendingThe Pod has not yet begun executing Init Containers.PodInitializing or RunningThe Pod has already finished executing Init Containers.


Question: How does Debug Init Containers work?

Answer: Debug Init ContainersThis page shows how to investigate problems related to the execution of Init Containers. The example command lines below refer to the Pod as <pod-name> and the Init Containers as <init-container-1> and <init-container-2>.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.You should be familiar with the basics of Init Containers.You should have Configured an Init Container.Checking the status of Init ContainersDisplay the status of your pod:kubectl get pod <pod-name> For example, a status of Init:1/2 indicates that one of two Init Containers has completed successfully:NAME READY STATUS RESTARTS AGE <pod-name> 0/1 Init:1/2 0 7s See Understanding Pod status for more examples of status values and their meanings.Getting details about Init ContainersView more detailed information about Init Container execution:kubectl describe pod <pod-name> For example, a Pod with two Init Containers might show the following:Init Containers: <init-container-1>: Container ID: ... ... State: Terminated Reason: Completed Exit Code: 0 Started: ... Finished: ... Ready: True Restart Count: 0 ... <init-container-2>: Container ID: ... ... State: Waiting Reason: CrashLoopBackOff Last State: Terminated Reason: Error Exit Code: 1 Started: ... Finished: ... Ready: False Restart Count: 3 ... You can also access the Init Container statuses programmatically by reading the status.initContainerStatuses field on the Pod Spec:kubectl get pod nginx --template '{{.status.initContainerStatuses}}' This command will return the same information as above in raw JSON.Accessing logs from Init ContainersPass the Init Container name along with the Pod name to access its logs.kubectl logs <pod-name> -c <init-container-2> Init Containers that run a shell script print commands as they're executed. For example, you can do this in Bash by running set -x at the beginning of the script.Understanding Pod statusA Pod status beginning with Init: summarizes the status of Init Container execution. The table below describes some example status values that you might see while debugging Init Containers.StatusMeaningInit:N/MThe Pod has M Init Containers, and N have completed so far.Init:ErrorAn Init Container has failed to execute.Init:CrashLoopBackOffAn Init Container has failed repeatedly.PendingThe Pod has not yet begun executing Init Containers.PodInitializing or RunningThe Pod has already finished executing Init Containers.


Question: When would you use Debug Init Containers?

Answer: Debug Init ContainersThis page shows how to investigate problems related to the execution of Init Containers. The example command lines below refer to the Pod as <pod-name> and the Init Containers as <init-container-1> and <init-container-2>.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.You should be familiar with the basics of Init Containers.You should have Configured an Init Container.Checking the status of Init ContainersDisplay the status of your pod:kubectl get pod <pod-name> For example, a status of Init:1/2 indicates that one of two Init Containers has completed successfully:NAME READY STATUS RESTARTS AGE <pod-name> 0/1 Init:1/2 0 7s See Understanding Pod status for more examples of status values and their meanings.Getting details about Init ContainersView more detailed information about Init Container execution:kubectl describe pod <pod-name> For example, a Pod with two Init Containers might show the following:Init Containers: <init-container-1>: Container ID: ... ... State: Terminated Reason: Completed Exit Code: 0 Started: ... Finished: ... Ready: True Restart Count: 0 ... <init-container-2>: Container ID: ... ... State: Waiting Reason: CrashLoopBackOff Last State: Terminated Reason: Error Exit Code: 1 Started: ... Finished: ... Ready: False Restart Count: 3 ... You can also access the Init Container statuses programmatically by reading the status.initContainerStatuses field on the Pod Spec:kubectl get pod nginx --template '{{.status.initContainerStatuses}}' This command will return the same information as above in raw JSON.Accessing logs from Init ContainersPass the Init Container name along with the Pod name to access its logs.kubectl logs <pod-name> -c <init-container-2> Init Containers that run a shell script print commands as they're executed. For example, you can do this in Bash by running set -x at the beginning of the script.Understanding Pod statusA Pod status beginning with Init: summarizes the status of Init Container execution. The table below describes some example status values that you might see while debugging Init Containers.StatusMeaningInit:N/MThe Pod has M Init Containers, and N have completed so far.Init:ErrorAn Init Container has failed to execute.Init:CrashLoopBackOffAn Init Container has failed repeatedly.PendingThe Pod has not yet begun executing Init Containers.PodInitializing or RunningThe Pod has already finished executing Init Containers.


Question: What are the benefits of Debug Init Containers?

Answer: Debug Init ContainersThis page shows how to investigate problems related to the execution of Init Containers. The example command lines below refer to the Pod as <pod-name> and the Init Containers as <init-container-1> and <init-container-2>.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.You should be familiar with the basics of Init Containers.You should have Configured an Init Container.Checking the status of Init ContainersDisplay the status of your pod:kubectl get pod <pod-name> For example, a status of Init:1/2 indicates that one of two Init Containers has completed successfully:NAME READY STATUS RESTARTS AGE <pod-name> 0/1 Init:1/2 0 7s See Understanding Pod status for more examples of status values and their meanings.Getting details about Init ContainersView more detailed information about Init Container execution:kubectl describe pod <pod-name> For example, a Pod with two Init Containers might show the following:Init Containers: <init-container-1>: Container ID: ... ... State: Terminated Reason: Completed Exit Code: 0 Started: ... Finished: ... Ready: True Restart Count: 0 ... <init-container-2>: Container ID: ... ... State: Waiting Reason: CrashLoopBackOff Last State: Terminated Reason: Error Exit Code: 1 Started: ... Finished: ... Ready: False Restart Count: 3 ... You can also access the Init Container statuses programmatically by reading the status.initContainerStatuses field on the Pod Spec:kubectl get pod nginx --template '{{.status.initContainerStatuses}}' This command will return the same information as above in raw JSON.Accessing logs from Init ContainersPass the Init Container name along with the Pod name to access its logs.kubectl logs <pod-name> -c <init-container-2> Init Containers that run a shell script print commands as they're executed. For example, you can do this in Bash by running set -x at the beginning of the script.Understanding Pod statusA Pod status beginning with Init: summarizes the status of Init Container execution. The table below describes some example status values that you might see while debugging Init Containers.StatusMeaningInit:N/MThe Pod has M Init Containers, and N have completed so far.Init:ErrorAn Init Container has failed to execute.Init:CrashLoopBackOffAn Init Container has failed repeatedly.PendingThe Pod has not yet begun executing Init Containers.PodInitializing or RunningThe Pod has already finished executing Init Containers.


Question: What is Debug Init Containers?

Answer: T h i s   p a g e   s h o w s   h o w   t o   i n v e s t i g a t e   p r o b l e m s   r e l a t e d   t o   t h e   e x e c u t i o n   o f   I n i t   C o n t a i n e r s .   T h e   e x a m p l e   c o m m a n d   l i n e s   b e l o w   r e f e r   t o   t h e   P o d   a s   < p o d - n a m e >   a n d   t h e   I n i t   C o n t a i n e r s   a s   < i n i t - c o n t a i n e r - 1 >   a n d   < i n i t - c o n t a i n e r - 2 > .


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 .   Y o u   s h o u l d   b e   f a m i l i a r   w i t h   t h e   b a s i c s   o f   I n i t   C o n t a i n e r s . Y o u


Question: What is Checking the status of Init Containers?

Answer: D i s p l a y   t h e   s t a t u s   o f   y o u r   p o d :   k u b e c t l   g e t   p o d   < p o d - n a m e >   F o r   e x a m p l e ,   a   s t a t u s   o f   I n i t : 1 / 2   i n d i c a t e s   t h a t   o n e   o f   t w o   I n i t   C o n t a i n e r s   h a s   c o m p l e t e d   s u c c e s s f u l l y :   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   < p o d - n a m e >   0 / 1   I n i t : 1 / 2   0   7 s   S e e   U n d e r s t a n d i n g   P o d   s t a t u s   f o r   m o r e   e x a m p l e s   o f   s t a t u s   v a l u e s   a n d   t h e i r   m e a n i n g s .


Question: What is Getting details about Init Containers?

Answer: V i e w   m o r e   d e t a i l e d   i n f o r m a t i o n   a b o u t   I n i t   C o n t a i n e r   e x e c u t i o n :   k u b e c t l   d e s c r i b e   p o d   < p o d - n a m e >   F o r   e x a m p l e ,   a   P o d   w i t h   t w o   I n i t   C o n t a i n e r s   m i g h t   s h o w   t h e   f o l l o w i n g :   I n i t   C o n t a i n e r s :   < i n i t - c o n t a i n e r - 1 > :   C o n t a i n e r   I D :   . . .   . . .   S t a t e :   T e r m i n a t e d   R e a s o n :   C o m p l e t e d   E x i t   C o d e :   0   S t a r t e d :   . . .   F i n i s h e d :   . . .   R e a d y :   T r u e   R e s t a r t   C o u n t :   0   . . .   < i n i t - c o n t a i n e r - 2 > :   C o n t a i n e r   I D :   . . .   . . .   S t a t e :   W a i t i n g   R e a s o n :   C r a s h L o o p B a c k O f f   L a s t   S t a t e :   T e r m i n a t e d   R e a s o n :   E r r o r   E x i t   C o d e :   1   S t a r t e d :   . . .   F i n i s h e d :   . . .   R e a d y :   F a l s e   R e s t a r t   C o u n t :   3   . . .   Y o u   c a n   a l s o   a c c e s s   t h e   I n i t   C o n t a i n e r   s t a t u s e s   p r o g r a m m a t i c a l l y   b y   r e a d i n g   t h e   s t a t u s . i n i t C o n t a i n e r S t a t u s e s   f i e l d   o n   t h e   P o d   S p e c :   k u b e c t l   g e t   p o d   n g i n x   - - t e m p l a t e   ' { { . s t a t u s . i n i t C o n t a i n e r S t a t u s e s } } '   T h i s   c o m m a n d   w i l l   r e t u r n   t h e   s a m e   i n f o r m a t i o n   a s   a b o v e   i n   r a w   J S O N .


Question: What is Accessing logs from Init Containers?

Answer: P a s s   t h e   I n i t   C o n t a i n e r   n a m e   a l o n g   w i t h   t h e   P o d   n a m e   t o   a c c e s s   i t s   l o g s .   k u b e c t l   l o g s   < p o d - n a m e >   - c   < i n i t - c o n t a i n e r - 2 >   I n i t   C o n t a i n e r s   t h a t   r u n   a   s h e l l   s c r i p t   p r i n t   c o m m a n d s   a s   t h e y ' r e   e x e c u t e d .   F o r   e x a m p l e ,   y o u   c a n   d o   t h i s   i n   B a s h   b y   r u n n i n g   s e t   - x   a t   t h e   b e g i n n i n g   o f   t h e   s c r i p t .


Question: What is Understanding Pod status?

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


Question: What is Service?

Answer: ServiceExpose an application running in your cluster behind a single outward-facing endpoint, even when the workload is split across multiple backends.In Kubernetes, a Service is a method for exposing a network application that is running as one or more Pods in your cluster.A key aim of Services in Kubernetes is that you don't need to modify your existing application to use an unfamiliar service discovery mechanism. You can run code in Pods, whether this is a code designed for a cloud-native world, or an older app you've containerized. You use a Service to make that set of Pods available on the network so that clients can interact with it.If you use a Deployment to run your app, that Deployment can create and destroy Pods dynamically. From one moment to the


Question: How does Service work?

Answer: ServiceExpose an application running in your cluster behind a single outward-facing endpoint, even when the workload is split across multiple backends.In Kubernetes, a Service is a method for exposing a network application that is running as one or more Pods in your cluster.A key aim of Services in Kubernetes is that you don't need to modify your existing application to use an unfamiliar service discovery mechanism. You can run code in Pods, whether this is a code designed for a cloud-native world, or an older app you've containerized. You use a Service to make that set of Pods available on the network so that clients can interact with it.If you use a Deployment to run your app, that Deployment can create and destroy Pods dynamically. From one moment to the


Question: When would you use Service?

Answer: ServiceExpose an application running in your cluster behind a single outward-facing endpoint, even when the workload is split across multiple backends.In Kubernetes, a Service is a method for exposing a network application that is running as one or more Pods in your cluster.A key aim of Services in Kubernetes is that you don't need to modify your existing application to use an unfamiliar service discovery mechanism. You can run code in Pods, whether this is a code designed for a cloud-native world, or an older app you've containerized. You use a Service to make that set of Pods available on the network so that clients can interact with it.If you use a Deployment to run your app, that Deployment can create and destroy Pods dynamically. From one moment to the


Question: What are the benefits of Service?

Answer: ServiceExpose an application running in your cluster behind a single outward-facing endpoint, even when the workload is split across multiple backends.In Kubernetes, a Service is a method for exposing a network application that is running as one or more Pods in your cluster.A key aim of Services in Kubernetes is that you don't need to modify your existing application to use an unfamiliar service discovery mechanism. You can run code in Pods, whether this is a code designed for a cloud-native world, or an older app you've containerized. You use a Service to make that set of Pods available on the network so that clients can interact with it.If you use a Deployment to run your app, that Deployment can create and destroy Pods dynamically. From one moment to the


Question: What is Service?

Answer: I n   K u b e r n e t e s ,   a   S e r v i c e   i s   a   m e t h o d   f o r   e x p o s i n g   a   n e t w o r k   a p p l i c a t i o n   t h a t   i s   r u n n i n g   a s   o n e   o r   m o r e   P o d s   i n   y o u r   c l u s t e r .   A   k e y   a i m   o f   S e r v i c e s   i n   K u b e r n e t e s   i s   t h a t   y o u   d o n ' t   n e e d   t o   m o d i f y   y o u r   e x i s t i n g   a p p l i c a t i o n   t o   u s e   a n   u n f a m i l i a r   s e r v i c e   d i s c o v e r y   m e c h a n i s m .   Y o u   c a n   r u n   c o d e   i n   P o d s ,   w h e t h e r   t h i s   i s   a   c o d e   d e s i g n e d   f o r   a   c l o u d - n a t i v e   w o r l d ,   o r   a n   o l d e r   a p p   y o u ' v e   c o n t a i n e r i z e d .   Y o u   u s e   a   S e r v i c e   t o   m a k e   t h a t   s e t   o f   P o d s   a v a i l a b l e   o n   t h e   n e t w o r k   s o   t h a t   c l i e n t s   c a n   i n t e r a c t   w i t h   i t .   I f   y o u   u s e   a   D e p l o y m e n t   t o   r u n   y o u r   a p p ,   t h a t   D e p l o y m e n t   c a n   c r e a t e   a n d   d e s t r o y   P o d s   d y n a m i c a l l y .   F r o m   o n e   m o m e n t   t o   t h e   n e x t ,   y o u   d o n ' t   k n o w   h o w   m a n y   o f   t h o s e   P o d s   a r e   w o r k i n g   a n d   h e a l t h y ;   y o u   m i g h t   n o t   e v e n   k n o w   w h a t   t h o s e   h e a l t h y   P o d s   a r e   n a m e d .   K u b e r n e t e s   P o d s   a r e   c r e a t e d   a n d   d e s t r o y e d   t o   m a t c h   t h e   d e s i r e d   s t a t e   o f   y o u r   c l u s t e r .   P o d s   a r e   e p h e m e r a l   r e s o u r c e s   ( y o u   s h o u l d   n o t   e x p e c t   t h a t   a n   i n d i v i d u a l   P o d   i s   r e l i a b l e   a n d   d u r a b l e ) .   E a c h   P o d   g e t s   i t s   o w n   I P   a d d r e s s   ( K u b e r n e t e s   e x p e c t s   n e t w o r k   p l u g i


Question: What is Services in Kubernetes?

Answer: T h e   S e r v i c e   A P I ,   p a r t   o f   K u b e r n e t e s ,   i s   a n   a b s t r a c t i o n   t o   h e l p   y o u   e x p o s e   g r o u p s   o f   P o d s   o v e r   a   n e t w o r k .   E a c h   S e r v i c e   o b j e c t   d e f i n e s   a   l o g i c a l   s e t   o f   e n d p o i n t s   ( u s u a l l y   t h e s e   e n d p o i n t s   a r e   P o d s )   a l o n g   w i t h   a   p o l i c y   a b o u t   h o w   t o   m a k e   t h o s e   p o d s   a c c e s s i b l e .   F o r   e x a m p l e ,   c o n s i d e r   a   s t a t e l e s s   i m a g e - p r o c e s s i n g   b a c k e n d   w h i c h   i s   r u n n i n g   w i t h   3   r e p l i c a s .   T h o s e   r e p l i c a s   a r e   f u n g i b l e — f r o n t e n d s   d o   n o t   c a r e   w h i c h   b a c k e n d   t h e y   u s e .   W h i l e   t h e   a c t u a l   P o d s   t h a t   c o m p o s e   t h e   b a c k e n d   s e t   m a y   c h a n g e ,   t h e   f r o n t e n d   c l i e n t s   s h o u l d   n o t   n e e d   t o   b e   a w a r e   o f   t h a t ,   n o r   s h o u l d   t h e y   n e e d   t o   k e e p   t r a c k   o f   t h e   s e t   o f   b a c k e n d s   t h e m s e l v e s .   T h e   S e r v i c e   a b s t r a c t i o n   e n a b l e s   t h i s   d e c o u p l i n g .   T h e   s e t   o f   P o d s   t a r g e t e d   b y   a   S e r v i c e   i s   u s u a l l y   d e t e r m i n e d   b y   a   s e l e c t o r   t h a t   y o u   d e f i n e .   T o   l e a r n   a b o u t   o t h e r   w a y s   t o   d e f i n e   S e r v i c e   e n d p o i n t s ,   s e e   S e r v i c e s   w i t h o u t   s e l e c t o r s .   I f   y o u r   w o r k l o a d   s p e a k s   H T T P ,   y o u   m i g h t   c h o o s e   t o   u s e   a n   I n g r e s s   t o   c o n t r o l   h o w   w e b   t r a f f i c   r e a c h e s   t h a t   w o r k l o a d .   I n g r e s s   i s   n o t   a   S e r v i c e   t y p e ,   b u t   i t   a c t s   a


Question: What is Cloud-native service discovery?

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


Question: What is Defining a Service?

Answer: A   S e r v i c e   i s   a n   o b j e c t   ( t h e   s a m e   w a y   t h a t   a   P o d   o r   a   C o n f i g M a p   i s   a n   o b j e c t ) .   Y o u   c a n   c r e a t e ,   v i e w   o r   m o d i f y   S e r v i c e   d e f i n i t i o n s   u s i n g   t h e   K u b e r n e t e s   A P I .   U s u a l l y   y o u   u s e   a   t o o l   s u c h   a s   k u b e c t l   t o   m a k e   t h o s e   A P I   c a l l s   f o r   y o u .   F o r   e x a m p l e ,   s u p p o s e   y o u   h a v e   a   s e t   o f   P o d s   t h a t   e a c h   l i s t e n   o n   T C P   p o r t   9 3 7 6   a n d   a r e   l a b e l l e d   a s   a p p . k u b e r n e t e s . i o / n a m e = M y A p p .   Y o u   c a n   d e f i n e   a   S e r v i c e   t o   p u b l i s h   t h a t   T C P   l i s t e n e r :   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   m y - s e r v i c e   s p e c :   s e l e c t o r :   a p p . k u b e r n e t e s . i o / n a m e :   M y A p p   p o r t s :   -   p r o t o c o l :   T C P   p o r t :   8 0   t a r g e t P o r t :   9 3 7 6   A p p l y i n g   t h i s   m a n i f e s t   c r e a t e s   a   n e w   S e r v i c e   n a m e d   " m y - s e r v i c e "   w i t h   t h e   d e f a u l t   C l u s t e r I P   s e r v i c e   t y p e .   T h e   S e r v i c e   t a r g e t s   T C P   p o r t   9 3 7 6   o n   a n y   P o d   w i t h   t h e   a p p . k u b e r n e t e s . i o / n a m e :   M y A p p   l a b e l .   K u b e r n e t e s   a s s i g n s   t h i s   S e r v i c e   a n   I P   a d d r e s s   ( t h e   c l u s t e r   I P ) ,   t h a t   i s   u s e d   b y   t h e   v i r t u a l   I P   a d d r e s s   m e c h a n i s m .   F o r   m o r e   d e t a i l s   o n   t h a t   m e c h a n i s m ,   r e a d   V i r t u a l   I P s   a n d   S e r v i c e   P r o x i e s .   T h e   c o n t r o l l e r   f o r   t h a t   S e r v i c e   c o n t i n u o u s l y   s c a n s   f o r


Question: What is Relaxed naming requirements for Service objects?

Answer: T h e   R e l a x e d S e r v i c e N a m e V a l i d a t i o n   f e a t u r e   g a t e   a l l o w s   S e r v i c e   o b j e c t   n a m e s   t o   s t a r t   w i t h   a   d i g i t .   W h e n   t h i s   f e a t u r e   g a t e   i s   e n a b l e d ,   S e r v i c e   o b j e c t   n a m e s   m u s t   b e   v a l i d   R F C   1 1 2 3   l a b e l   n a m e s .


Question: What is Port definitions?

Answer: P o r t   d e f i n i t i o n s   i n   P o d s   h a v e   n a m e s ,   a n d   y o u   c a n   r e f e r e n c e   t h e s e   n a m e s   i n   t h e   t a r g e t P o r t   a t t r i b u t e   o f   a   S e r v i c e .   F o r   e x a m p l e ,   w e   c a n   b i n d   t h e   t a r g e t P o r t   o f   t h e   S e r v i c e   t o   t h e   P o d   p o r t   i n   t h e   f o l l o w i n g   w a y :   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 :   n g i n x   l a b e l s :   a p p . k u b e r n e t e s . i o / n a m e :   p r o x y   s p e c :   c o n t a i n e r s :   -   n a m e :   n g i n x   i m a g e :   n g i n x : s t a b l e   p o r t s :   -   c o n t a i n e r P o r t :   8 0   n a m e :   h t t p - w e b - s v c   - - -   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   n g i n x - s e r v i c e   s p e c :   s e l e c t o r :   a p p . k u b e r n e t e s . i o / n a m e :   p r o x y   p o r t s :   -   n a m e :   n a m e - o f - s e r v i c e - p o r t   p r o t o c o l :   T C P   p o r t :   8 0   t a r g e t P o r t :   h t t p - w e b - s v c   T h i s   w o r k s   e v e n   i f   t h e r e   i s   a   m i x t u r e   o f   P o d s   i n   t h e   S e r v i c e   u s i n g   a   s i n g l e   c o n f i g u r e d   n a m e ,   w i t h   t h e   s a m e   n e t w o r k   p r o t o c o l   a v a i l a b l e   v i a   d i f f e r e n t   p o r t   n u m b e r s .   T h i s   o f f e r s   a   l o t   o f   f l e x i b i l i t y   f o r   d e p l o y i n g   a n d   e v o l v i n g   y o u r   S e r v i c e s .   F o r   e x a m p l e ,   y o u   c a n   c h a n g e   t h e   p o r t   n u m b e r s   t h a t   P o d s   e x p o s e   i n   t h e   n e x t   v e r s i o n   o f   y o u r   b a c k e n d   s o f t w a r e ,   w i t h o u t   b r e a k i n g   c l i e n t s .   T h e   d e f a u l t   p r o t o c o l   f o r   S e r v i c e s   i s   T C P ;   y o u   c


Question: What is Services without selectors?

Answer: S e r v i c e s   m o s t   c o m m o n l y   a b s t r a c t   a c c e s s   t o   K u b e r n e t e s   P o d s   t h a n k s   t o   t h e   s e l e c t o r ,   b u t   w h e n   u s e d   w i t h   a   c o r r e s p o n d i n g   s e t   o f   E n d p o i n t S l i c e s   o b j e c t s   a n d   w i t h o u t   a   s e l e c t o r ,   t h e   S e r v i c e   c a n   a b s t r a c t   o t h e r   k i n d s   o f   b a c k e n d s ,   i n c l u d i n g   o n e s   t h a t   r u n   o u t s i d e   t h e   c l u s t e r .   F o r   e x a m p l e :   Y o u   w a n t   t o   h a v e   a n   e x t e r n a l   d a t a b a s e   c l u s t e r   i n   p r o d u c t i o n ,   b u t   i n   y o u r   t e s t   e n v i r o n m e n t   y o u   u s e   y o u r   o w n   d a t a b a s e s . Y o u   w a n t   t o   p o i n t   y o u r   S e r v i c e   t o   a   S e r v i c e   i n   a   d i f f e r e n t   N a m e s p a c e   o r   o n   a n o t h e r   c l u s t e r . Y o u   a r e   m i g r a t i n g   a   w o r k l o a d   t o   K u b e r n e t e s .   W h i l e   e v a l u a t i n g   t h e   a p p r o a c h ,   y o u   r u n   o n l y   a   p o r t i o n   o f   y o u r   b a c k e n d s   i n   K u b e r n e t e s .   I n   a n y   o f   t h e s e   s c e n a r i o s   y o u   c a n   d e f i n e   a   S e r v i c e   w i t h o u t   s p e c i f y i n g   a   s e l e c t o r   t o   m a t c h   P o d s .   F o r   e x a m p l e :   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   m y - s e r v i c e   s p e c :   p o r t s :   -   n a m e :   h t t p   p r o t o c o l :   T C P   p o r t :   8 0   t a r g e t P o r t :   9 3 7 6   B e c a u s e   t h i s   S e r v i c e   h a s   n o   s e l e c t o r ,   t h e   c o r r e s p o n d i n g   E n d p o i n t S l i c e   o b j e c t s   a r e   n o t   c r e a t e d   a u t o m a t i c a l l y .   Y o u   c a n   m a p   t h e   S e r v i c e   t o   t h e   n e t w o r k   a d d r


Question: What is Custom EndpointSlices?

Answer: W h e n   y o u   c r e a t e   a n   E n d p o i n t S l i c e   o b j e c t   f o r   a   S e r v i c e ,   y o u   c a n   u s e   a n y   n a m e   f o r   t h e   E n d p o i n t S l i c e .   E a c h   E n d p o i n t S l i c e   i n   a   n a m e s p a c e   m u s t   h a v e   a   u n i q u e   n a m e .   Y o u   l i n k   a n   E n d p o i n t S l i c e   t o   a   S e r v i c e   b y   s e t t i n g   t h e   k u b e r n e t e s . i o / s e r v i c e - n a m e   l a b e l   o n   t h a t   E n d p o i n t S l i c e .


Question: What is Note:?

Answer: T h e   e n d p o i n t   I P s   m u s t   n o t   b e :   l o o p b a c k   ( 1 2 7 . 0 . 0 . 0 / 8   f o r   I P v 4 ,   : : 1 / 1 2 8   f o r   I P v 6 ) ,   o r   l i n k - l o c a l   ( 1 6 9 . 2 5 4 . 0 . 0 / 1 6   a n d   2 2 4 . 0 . 0 . 0 / 2 4   f o r   I P v 4 ,   f e 8 0 : : / 6 4   f o r   I P v 6 ) .   T h e   e n d p o i n t   I P   a d d r e s s e s   c a n n o t   b e   t h e   c l u s t e r   I P s   o f   o t h e r   K u b e r n e t e s   S e r v i c e s ,   b e c a u s e   k u b e - p r o x y   d o e s n ' t   s u p p o r t   v i r t u a l   I P s   a s   a   d e s t i n a t i o n .   F o r   a n   E n d p o i n t S l i c e   t h a t   y o u   c r e a t e   y o u r s e l f ,   o r   i n   y o u r   o w n   c o d e ,   y o u   s h o u l d   a l s o   p i c k   a   v a l u e   t o   u s e   f o r   t h e   l a b e l   e n d p o i n t s l i c e . k u b e r n e t e s . i o / m a n a g e d - b y .   I f   y o u   c r e a t e   y o u r   o w n   c o n t r o l l e r   c o d e   t o   m a n a g e   E n d p o i n t S l i c e s ,   c o n s i d e r   u s i n g   a   v a l u e   s i m i l a r   t o   " m y - d o m a i n . e x a m p l e / n a m e - o f - c o n t r o l l e r " .   I f   y o u   a r e   u s i n g   a   t h i r d   p a r t y   t o o l ,   u s e   t h e   n a m e   o f   t h e   t o o l   i n   a l l - l o w e r c a s e   a n d   c h a n g e   s p a c e s   a n d   o t h e r   p u n c t u a t i o n   t o   d a s h e s   ( - ) .   I f   p e o p l e   a r e   d i r e c t l y   u s i n g   a   t o o l   s u c h   a s   k u b e c t l   t o   m a n a g e   E n d p o i n t S l i c e s ,   u s e   a   n a m e   t h a t   d e s c r i b e s   t h i s   m a n u a l   m a n a g e m e n t ,   s u c h   a s   " s t a f f "   o r   " c l u s t e r - a d m i n s " .   Y o u   s h o u l d   a v o i d   u s i n g   t h e   r e s e r v e d   v a l u e   " c o n t r o l l e r " ,   w h i c h   i d e n t i f i e s   E n d p o i n t S l i c e s   m a n a g e d   b y


Question: What is Accessing a Service without a selector?

Answer: A c c e s s i n g   a   S e r v i c e   w i t h o u t   a   s e l e c t o r   w o r k s   t h e   s a m e   a s   i f   i t   h a d   a   s e l e c t o r .   I n   t h e   e x a m p l e   f o r   a   S e r v i c e   w i t h o u t   a   s e l e c t o r ,   t r a f f i c   i s   r o u t e d   t o   o n e   o f   t h e   t w o   e n d p o i n t s   d e f i n e d   i n   t h e   E n d p o i n t S l i c e   m a n i f e s t :   a   T C P   c o n n e c t i o n   t o   1 0 . 1 . 2 . 3   o r   1 0 . 4 . 5 . 6 ,   o n   p o r t   9 3 7 6 .


Question: What is Note:?

Answer: A n   E x t e r n a l N a m e   S e r v i c e   i s   a   s p e c i a l   c a s e   o f   S e r v i c e   t h a t   d o e s   n o t   h a v e   s e l e c t o r s   a n d   u s e s   D N S   n a m e s   i n s t e a d .   F o r   m o r e   i n f o r m a t i o n ,   s e e   t h e   E x t e r n a l N a m e   s e c t i o n .


Question: What is EndpointSlices?

Answer: E n d p o i n t S l i c e s   a r e   o b j e c t s   t h a t   r e p r e s e n t   a   s u b s e t   ( a   s l i c e )   o f   t h e   b a c k i n g   n e t w o r k   e n d p o i n t s   f o r   a   S e r v i c e .   Y o u r   K u b e r n e t e s   c l u s t e r   t r a c k s   h o w   m a n y   e n d p o i n t s   e a c h   E n d p o i n t S l i c e   r e p r e s e n t s .   I f   t h e r e   a r e   s o   m a n y   e n d p o i n t s   f o r   a   S e r v i c e   t h a t   a   t h r e s h o l d   i s   r e a c h e d ,   t h e n   K u b e r n e t e s   a d d s   a n o t h e r   e m p t y   E n d p o i n t S l i c e   a n d   s t o r e s   n e w   e n d p o i n t   i n f o r m a t i o n   t h e r e .   B y   d e f a u l t ,   K u b e r n e t e s   m a k e s   a   n e w   E n d p o i n t S l i c e   o n c e   t h e   e x i s t i n g   E n d p o i n t S l i c e s   a l l   c o n t a i n   a t   l e a s t   1 0 0   e n d p o i n t s .   K u b e r n e t e s   d o e s   n o t   m a k e   t h e   n e w   E n d p o i n t S l i c e   u n t i l   a n   e x t r a   e n d p o i n t   n e e d s   t o   b e   a d d e d .   S e e   E n d p o i n t S l i c e s   f o r   m o r e   i n f o r m a t i o n   a b o u t   t h i s   A P I .


Question: What is Endpoints (deprecated)?

Answer: T h e   E n d p o i n t S l i c e   A P I   i s   t h e   e v o l u t i o n   o f   t h e   o l d e r   E n d p o i n t s   A P I .   T h e   d e p r e c a t e d   E n d p o i n t s   A P I   h a s   s e v e r a l   p r o b l e m s   r e l a t i v e   t o   E n d p o i n t S l i c e :   I t   d o e s   n o t   s u p p o r t   d u a l - s t a c k   c l u s t e r s . I t   d o e s   n o t   c o n t a i n   i n f o r m a t i o n   n e e d e d   t o   s u p p o r t   n e w e r   f e a t u r e s ,   s u c h   a s   t r a f f i c D i s t r i b u t i o n . I t   w i l l   t r u n c a t e   t h e   l i s t   o f   e n d p o i n t s   i f   i t   i s   t o o   l o n g   t o   f i t   i n   a   s i n g l e   o b j e c t .   B e c a u s e   o f   t h i s ,   i t   i s   r e c o m m e n d e d   t h a t   a l l   c l i e n t s   u s e   t h e   E n d p o i n t S l i c e   A P I   r a t h e r   t h a n   E n d p o i n t s .


Question: What is Over-capacity endpoints?

Answer: K u b e r n e t e s   l i m i t s   t h e   n u m b e r   o f   e n d p o i n t s   t h a t   c a n   f i t   i n   a   s i n g l e   E n d p o i n t s   o b j e c t .   W h e n   t h e r e   a r e   o v e r   1 0 0 0   b a c k i n g   e n d p o i n t s   f o r   a   S e r v i c e ,   K u b e r n e t e s   t r u n c a t e s   t h e   d a t a   i n   t h e   E n d p o i n t s   o b j e c t .   B e c a u s e   a   S e r v i c e   c a n   b e   l i n k e d   w i t h   m o r e   t h a n   o n e   E n d p o i n t S l i c e ,   t h e   1 0 0 0   b a c k i n g   e n d p o i n t   l i m i t   o n l y   a f f e c t s   t h e   l e g a c y   E n d p o i n t s   A P I .   I n   t h a t   c a s e ,   K u b e r n e t e s   s e l e c t s   a t   m o s t   1 0 0 0   p o s s i b l e   b a c k e n d   e n d p o i n t s   t o   s t o r e   i n t o   t h e   E n d p o i n t s   o b j e c t ,   a n d   s e t s   a n   a n n o t a t i o n   o n   t h e   E n d p o i n t s :   e n d p o i n t s . k u b e r n e t e s . i o / o v e r - c a p a c i t y :   t r u n c a t e d .   T h e   c o n t r o l   p l a n e   a l s o   r e m o v e s   t h a t   a n n o t a t i o n   i f   t h e   n u m b e r   o f   b a c k e n d   P o d s   d r o p s   b e l o w   1 0 0 0 .   T r a f f i c   i s   s t i l l   s e n t   t o   b a c k e n d s ,   b u t   a n y   l o a d   b a l a n c i n g   m e c h a n i s m   t h a t   r e l i e s   o n   t h e   l e g a c y   E n d p o i n t s   A P I   o n l y   s e n d s   t r a f f i c   t o   a t   m o s t   1 0 0 0   o f   t h e   a v a i l a b l e   b a c k i n g   e n d p o i n t s .   T h e   s a m e   A P I   l i m i t   m e a n s   t h a t   y o u   c a n n o t   m a n u a l l y   u p d a t e   a n   E n d p o i n t s   t o   h a v e   m o r e   t h a n   1 0 0 0   e n d p o i n t s .


Question: What is Application protocol?

Answer: T h e   a p p P r o t o c o l   f i e l d   p r o v i d e s   a   w a y   t o   s p e c i f y   a n   a p p l i c a t i o n   p r o t o c o l   f o r   e a c h   S e r v i c e   p o r t .   T h i s   i s   u s e d   a s   a   h i n t   f o r   i m p l e m e n t a t i o n s   t o   o f f e r   r i c h e r   b e h a v i o r   f o r   p r o t o c o l s   t h a t   t h e y   u n d e r s t a n d .   T h e   v a l u e   o f   t h i s   f i e l d   i s   m i r r o r e d   b y   t h e   c o r r e s p o n d i n g   E n d p o i n t s   a n d   E n d p o i n t S l i c e   o b j e c t s .   T h i s   f i e l d   f o l l o w s   s t a n d a r d   K u b e r n e t e s   l a b e l   s y n t a x .   V a l i d   v a l u e s   a r e   o n e   o f :   I A N A   s t a n d a r d   s e r v i c e   n a m e s . I m p l e m e n t a t i o n - d e f i n e d   p r e f i x e d   n a m e s   s u c h   a s   m y c o m p a n y . c o m / m y - c u s t o m - p r o t o c o l . K u b e r n e t e s - d e f i n e d   p r e f i x e d   n a m e s :   I A N A   s t a n d a r d   s e r v i c e   n a m e s .   I m p l e m e n t a t i o n - d e f i n e d   p r e f i x e d   n a m e s   s u c h   a s   m y c o m p a n y . c o m / m y - c u s t o m - p r o t o c o l .   K u b e r n e t e s - d e f i n e d   p r e f i x e d   n a m e s :


Question: What is Multi-port Services?

Answer: F o r   s o m e   S e r v i c e s ,   y o u   n e e d   t o   e x p o s e   m o r e   t h a n   o n e   p o r t .   K u b e r n e t e s   l e t s   y o u   c o n f i g u r e   m u l t i p l e   p o r t   d e f i n i t i o n s   o n   a   S e r v i c e   o b j e c t .   W h e n   u s i n g   m u l t i p l e   p o r t s   f o r   a   S e r v i c e ,   y o u   m u s t   g i v e   a l l   o f   y o u r   p o r t s   n a m e s   s o   t h a t   t h e s e   a r e   u n a m b i g u o u s .   F o r   e x a m p l e :   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   m y - s e r v i c e   s p e c :   s e l e c t o r :   a p p . k u b e r n e t e s . i o / n a m e :   M y A p p   p o r t s :   -   n a m e :   h t t p   p r o t o c o l :   T C P   p o r t :   8 0   t a r g e t P o r t :   9 3 7 6   -   n a m e :   h t t p s   p r o t o c o l :   T C P   p o r t :   4 4 3   t a r g e t P o r t :   9 3 7 7


Question: What is Note:?

Answer: A s   w i t h   K u b e r n e t e s   n a m e s   i n   g e n e r a l ,   n a m e s   f o r   p o r t s   m u s t   o n l y   c o n t a i n   l o w e r c a s e   a l p h a n u m e r i c   c h a r a c t e r s   a n d   - .   P o r t   n a m e s   m u s t   a l s o   s t a r t   a n d   e n d   w i t h   a n   a l p h a n u m e r i c   c h a r a c t e r .   F o r   e x a m p l e ,   t h e   n a m e s   1 2 3 - a b c   a n d   w e b   a r e   v a l i d ,   b u t   1 2 3 _ a b c   a n d   - w e b   a r e   n o t .


Question: What is Service type?

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


Question: What is type: ClusterIP?

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


Question: What is Choosing your own IP address?

Answer: Y o u   c a n   s p e c i f y   y o u r   o w n   c l u s t e r   I P   a d d r e s s   a s   p a r t   o f   a   S e r v i c e   c r e a t i o n   r e q u e s t .   T o   d o   t h i s ,   s e t   t h e   . s p e c . c l u s t e r I P   f i e l d .   F o r   e x a m p l e ,   i f   y o u   a l r e a d y   h a v e   a n   e x i s t i n g   D N S   e n t r y   t h a t   y o u   w i s h   t o   r e u s e ,   o r   l e g a c y   s y s t e m s   t h a t   a r e   c o n f i g u r e d   f o r   a   s p e c i f i c   I P   a d d r e s s   a n d   d i f f i c u l t   t o   r e - c o n f i g u r e .   T h e   I P   a d d r e s s   t h a t   y o u   c h o o s e   m u s t   b e   a   v a l i d   I P v 4   o r   I P v 6   a d d r e s s   f r o m   w i t h i n   t h e   s e r v i c e - c l u s t e r - i p - r a n g e   C I D R   r a n g e   t h a t   i s   c o n f i g u r e d   f o r   t h e   A P I   s e r v e r .   I f   y o u   t r y   t o   c r e a t e   a   S e r v i c e   w i t h   a n   i n v a l i d   c l u s t e r I P   a d d r e s s   v a l u e ,   t h e   A P I   s e r v e r   w i l l   r e t u r n   a   4 2 2   H T T P   s t a t u s   c o d e   t o   i n d i c a t e   t h a t   t h e r e ' s   a   p r o b l e m .   R e a d   a v o i d i n g   c o l l i s i o n s   t o   l e a r n   h o w   K u b e r n e t e s   h e l p s   r e d u c e   t h e   r i s k   a n d   i m p a c t   o f   t w o   d i f f e r e n t   S e r v i c e s   b o t h   t r y i n g   t o   u s e   t h e   s a m e   I P   a d d r e s s .


Question: What is type: NodePort?

Answer: I f   y o u   s e t   t h e   t y p e   f i e l d   t o   N o d e P o r t ,   t h e   K u b e r n e t e s   c o n t r o l   p l a n e   a l l o c a t e s   a   p o r t   f r o m   a   r a n g e   s p e c i f i e d   b y   - - s e r v i c e - n o d e - p o r t - r a n g e   f l a g   ( d e f a u l t :   3 0 0 0 0 - 3 2 7 6 7 ) .   E a c h   n o d e   p r o x i e s   t h a t   p o r t   ( t h e   s a m e   p o r t   n u m b e r   o n   e v e r y   N o d e )   i n t o   y o u r   S e r v i c e .   Y o u r   S e r v i c e   r e p o r t s   t h e   a l l o c a t e d   p o r t   i n   i t s   . s p e c . p o r t s [ * ] . n o d e P o r t   f i e l d .   U s i n g   a   N o d e P o r t   g i v e s   y o u   t h e   f r e e d o m   t o   s e t   u p   y o u r   o w n   l o a d   b a l a n c i n g   s o l u t i o n ,   t o   c o n f i g u r e   e n v i r o n m e n t s   t h a t   a r e   n o t   f u l l y   s u p p o r t e d   b y   K u b e r n e t e s ,   o r   e v e n   t o   e x p o s e   o n e   o r   m o r e   n o d e s '   I P   a d d r e s s e s   d i r e c t l y .   F o r   a   n o d e   p o r t   S e r v i c e ,   K u b e r n e t e s   a d d i t i o n a l l y   a l l o c a t e s   a   p o r t   ( T C P ,   U D P   o r   S C T P   t o   m a t c h   t h e   p r o t o c o l   o f   t h e   S e r v i c e ) .   E v e r y   n o d e   i n   t h e   c l u s t e r   c o n f i g u r e s   i t s e l f   t o   l i s t e n   o n   t h a t   a s s i g n e d   p o r t   a n d   t o   f o r w a r d   t r a f f i c   t o   o n e   o f   t h e   r e a d y   e n d p o i n t s   a s s o c i a t e d   w i t h   t h a t   S e r v i c e .   Y o u ' l l   b e   a b l e   t o   c o n t a c t   t h e   t y p e :   N o d e P o r t   S e r v i c e ,   f r o m   o u t s i d e   t h e   c l u s t e r ,   b y   c o n n e c t i n g   t o   a n y   n o d e   u s i n g   t h e   a p p r o p r i a t e   p r o t o c o l   ( f o r   e x a m p l e :   T C P ) ,   a n d   t h e   a p p r o p r i a t e


Question: What is Choosing your own port?

Answer: I f   y o u   w a n t   a   s p e c i f i c   p o r t   n u m b e r ,   y o u   c a n   s p e c i f y   a   v a l u e   i n   t h e   n o d e P o r t   f i e l d .   T h e   c o n t r o l   p l a n e   w i l l   e i t h e r   a l l o c a t e   y o u   t h a t   p o r t   o r   r e p o r t   t h a t   t h e   A P I   t r a n s a c t i o n   f a i l e d .   T h i s   m e a n s   t h a t   y o u   n e e d   t o   t a k e   c a r e   o f   p o s s i b l e   p o r t   c o l l i s i o n s   y o u r s e l f .   Y o u   a l s o   h a v e   t o   u s e   a   v a l i d   p o r t   n u m b e r ,   o n e   t h a t ' s   i n s i d e   t h e   r a n g e   c o n f i g u r e d   f o r   N o d e P o r t   u s e .   H e r e   i s   a n   e x a m p l e   m a n i f e s t   f o r   a   S e r v i c e   o f   t y p e :   N o d e P o r t   t h a t   s p e c i f i e s   a   N o d e P o r t   v a l u e   ( 3 0 0 0 7 ,   i n   t h i s   e x a m p l e ) :   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   m y - s e r v i c e   s p e c :   t y p e :   N o d e P o r t   s e l e c t o r :   a p p . k u b e r n e t e s . i o / n a m e :   M y A p p   p o r t s :   -   p o r t :   8 0   #   B y   d e f a u l t   a n d   f o r   c o n v e n i e n c e ,   t h e   ` t a r g e t P o r t `   i s   s e t   t o   #   t h e   s a m e   v a l u e   a s   t h e   ` p o r t `   f i e l d .   t a r g e t P o r t :   8 0   #   O p t i o n a l   f i e l d   #   B y   d e f a u l t   a n d   f o r   c o n v e n i e n c e ,   t h e   K u b e r n e t e s   c o n t r o l   p l a n e   #   w i l l   a l l o c a t e   a   p o r t   f r o m   a   r a n g e   ( d e f a u l t :   3 0 0 0 0 - 3 2 7 6 7 )   n o d e P o r t :   3 0 0 0 7


Question: What is Reserve Nodeport ranges to avoid collisions?

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


Question: What is Custom IP address configuration for type: NodePort Services?

Answer: Y o u   c a n   s e t   u p   n o d e s   i n   y o u r   c l u s t e r   t o   u s e   a   p a r t i c u l a r   I P   a d d r e s s   f o r   s e r v i n g   n o d e   p o r t   s e r v i c e s .   Y o u   m i g h t   w a n t   t o   d o   t h i s   i f   e a c h   n o d e   i s   c o n n e c t e d   t o   m u l t i p l e   n e t w o r k s   ( f o r   e x a m p l e :   o n e   n e t w o r k   f o r   a p p l i c a t i o n   t r a f f i c ,   a n d   a n o t h e r   n e t w o r k   f o r   t r a f f i c   b e t w e e n   n o d e s   a n d   t h e   c o n t r o l   p l a n e ) .   I f   y o u   w a n t   t o   s p e c i f y   p a r t i c u l a r   I P   a d d r e s s ( e s )   t o   p r o x y   t h e   p o r t ,   y o u   c a n   s e t   t h e   - - n o d e p o r t - a d d r e s s e s   f l a g   f o r   k u b e - p r o x y   o r   t h e   e q u i v a l e n t   n o d e P o r t A d d r e s s e s   f i e l d   o f   t h e   k u b e - p r o x y   c o n f i g u r a t i o n   f i l e   t o   p a r t i c u l a r   I P   b l o c k ( s ) .   T h i s   f l a g   t a k e s   a   c o m m a - d e l i m i t e d   l i s t   o f   I P   b l o c k s   ( e . g .   1 0 . 0 . 0 . 0 / 8 ,   1 9 2 . 0 . 2 . 0 / 2 5 )   t o   s p e c i f y   I P   a d d r e s s   r a n g e s   t h a t   k u b e - p r o x y   s h o u l d   c o n s i d e r   a s   l o c a l   t o   t h i s   n o d e .   F o r   e x a m p l e ,   i f   y o u   s t a r t   k u b e - p r o x y   w i t h   t h e   - - n o d e p o r t - a d d r e s s e s = 1 2 7 . 0 . 0 . 0 / 8   f l a g ,   k u b e - p r o x y   o n l y   s e l e c t s   t h e   l o o p b a c k   i n t e r f a c e   f o r   N o d e P o r t   S e r v i c e s .   T h e   d e f a u l t   f o r   - - n o d e p o r t - a d d r e s s e s   i s   a n   e m p t y   l i s t .   T h i s   m e a n s   t h a t   k u b e - p r o x y   s h o u l d   c o n s i d e r   a l l   a v a i l a b l e   n e t w o r k   i n t e r f a c e s   f o r   N o d e P o r t .   ( T h a t ' s


Question: What is type: LoadBalancer?

Answer: O n   c l o u d   p r o v i d e r s   w h i c h   s u p p o r t   e x t e r n a l   l o a d   b a l a n c e r s ,   s e t t i n g   t h e   t y p e   f i e l d   t o   L o a d B a l a n c e r   p r o v i s i o n s   a   l o a d   b a l a n c e r   f o r   y o u r   S e r v i c e .   T h e   a c t u a l   c r e a t i o n   o f   t h e   l o a d   b a l a n c e r   h a p p e n s   a s y n c h r o n o u s l y ,   a n d   i n f o r m a t i o n   a b o u t   t h e   p r o v i s i o n e d   b a l a n c e r   i s   p u b l i s h e d   i n   t h e   S e r v i c e ' s   . s t a t u s . l o a d B a l a n c e r   f i e l d .   F o r   e x a m p l e :   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   m y - s e r v i c e   s p e c :   s e l e c t o r :   a p p . k u b e r n e t e s . i o / n a m e :   M y A p p   p o r t s :   -   p r o t o c o l :   T C P   p o r t :   8 0   t a r g e t P o r t :   9 3 7 6   c l u s t e r I P :   1 0 . 0 . 1 7 1 . 2 3 9   t y p e :   L o a d B a l a n c e r   s t a t u s :   l o a d B a l a n c e r :   i n g r e s s :   -   i p :   1 9 2 . 0 . 2 . 1 2 7   T r a f f i c   f r o m   t h e   e x t e r n a l   l o a d   b a l a n c e r   i s   d i r e c t e d   a t   t h e   b a c k e n d   P o d s .   T h e   c l o u d   p r o v i d e r   d e c i d e s   h o w   i t   i s   l o a d   b a l a n c e d .   T o   i m p l e m e n t   a   S e r v i c e   o f   t y p e :   L o a d B a l a n c e r ,   K u b e r n e t e s   t y p i c a l l y   s t a r t s   o f f   b y   m a k i n g   t h e   c h a n g e s   t h a t   a r e   e q u i v a l e n t   t o   y o u   r e q u e s t i n g   a   S e r v i c e   o f   t y p e :   N o d e P o r t .   T h e   c l o u d - c o n t r o l l e r - m a n a g e r   c o m p o n e n t   t h e n   c o n f i g u r e s   t h e   e x t e r n a l   l o a d   b a l a n c e r   t o   f o r w a r d   t r a f f i c   t o   t h a t   a s s i g n e d   n o d e   p o r t .   Y o u   c a n   c o n


Question: What is Note:?

Answer: T h e . s p e c . l o a d B a l a n c e r I P   f i e l d   f o r   a   S e r v i c e   w a s   d e p r e c a t e d   i n   K u b e r n e t e s   v 1 . 2 4 .   T h i s   f i e l d   w a s   u n d e r - s p e c i f i e d   a n d   i t s   m e a n i n g   v a r i e s   a c r o s s   i m p l e m e n t a t i o n s .   I t   a l s o   c a n n o t   s u p p o r t   d u a l - s t a c k   n e t w o r k i n g .   T h i s   f i e l d   m a y   b e   r e m o v e d   i n   a   f u t u r e   A P I   v e r s i o n .   I f   y o u ' r e   i n t e g r a t i n g   w i t h   a   p r o v i d e r   t h a t   s u p p o r t s   s p e c i f y i n g   t h e   l o a d   b a l a n c e r   I P   a d d r e s s ( e s )   f o r   a   S e r v i c e   v i a   a   ( p r o v i d e r   s p e c i f i c )   a n n o t a t i o n ,   y o u   s h o u l d   s w i t c h   t o   d o i n g   t h a t .   I f   y o u   a r e   w r i t i n g   c o d e   f o r   a   l o a d   b a l a n c e r   i n t e g r a t i o n   w i t h   K u b e r n e t e s ,   a v o i d   u s i n g   t h i s   f i e l d .   Y o u   c a n   i n t e g r a t e   w i t h   G a t e w a y   r a t h e r   t h a n   S e r v i c e ,   o r   y o u   c a n   d e f i n e   y o u r   o w n   ( p r o v i d e r   s p e c i f i c )   a n n o t a t i o n s   o n   t h e   S e r v i c e   t h a t   s p e c i f y   t h e   e q u i v a l e n t   d e t a i l .


Question: What is Node liveness impact on load balancer traffic?

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


Question: What is Load balancers with mixed protocol types?

Answer: B y   d e f a u l t ,   f o r   L o a d B a l a n c e r   t y p e   o f   S e r v i c e s ,   w h e n   t h e r e   i s   m o r e   t h a n   o n e   p o r t   d e f i n e d ,   a l l   p o r t s   m u s t   h a v e   t h e   s a m e   p r o t o c o l ,   a n d   t h e   p r o t o c o l   m u s t   b e   o n e   w h i c h   i s   s u p p o r t e d   b y   t h e   c l o u d   p r o v i d e r .   T h e   f e a t u r e   g a t e   M i x e d P r o t o c o l L B S e r v i c e   ( e n a b l e d   b y   d e f a u l t   f o r   t h e   k u b e - a p i s e r v e r   a s   o f   v 1 . 2 4 )   a l l o w s   t h e   u s e   o f   d i f f e r e n t   p r o t o c o l s   f o r   L o a d B a l a n c e r   t y p e   o f   S e r v i c e s ,   w h e n   t h e r e   i s   m o r e   t h a n   o n e   p o r t   d e f i n e d .


Question: What is Disabling load balancer NodePort allocation?

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


Question: What is Specifying class of load balancer implementation?

Answer: F o r   a   S e r v i c e   w i t h   t y p e   s e t   t o   L o a d B a l a n c e r ,   t h e   . s p e c . l o a d B a l a n c e r C l a s s   f i e l d   e n a b l e s   y o u   t o   u s e   a   l o a d   b a l a n c e r   i m p l e m e n t a t i o n   o t h e r   t h a n   t h e   c l o u d   p r o v i d e r   d e f a u l t .   B y   d e f a u l t ,   . s p e c . l o a d B a l a n c e r C l a s s   i s   n o t   s e t   a n d   a   L o a d B a l a n c e r   t y p e   o f   S e r v i c e   u s e s   t h e   c l o u d   p r o v i d e r ' s   d e f a u l t   l o a d   b a l a n c e r   i m p l e m e n t a t i o n   i f   t h e   c l u s t e r   i s   c o n f i g u r e d   w i t h   a   c l o u d   p r o v i d e r   u s i n g   t h e   - - c l o u d - p r o v i d e r   c o m p o n e n t   f l a g .   I f   y o u   s p e c i f y   . s p e c . l o a d B a l a n c e r C l a s s ,   i t   i s   a s s u m e d   t h a t   a   l o a d   b a l a n c e r   i m p l e m e n t a t i o n   t h a t   m a t c h e s   t h e   s p e c i f i e d   c l a s s   i s   w a t c h i n g   f o r   S e r v i c e s .   A n y   d e f a u l t   l o a d   b a l a n c e r   i m p l e m e n t a t i o n   ( f o r   e x a m p l e ,   t h e   o n e   p r o v i d e d   b y   t h e   c l o u d   p r o v i d e r )   w i l l   i g n o r e   S e r v i c e s   t h a t   h a v e   t h i s   f i e l d   s e t .   s p e c . l o a d B a l a n c e r C l a s s   c a n   b e   s e t   o n   a   S e r v i c e   o f   t y p e   L o a d B a l a n c e r   o n l y .   O n c e   s e t ,   i t   c a n n o t   b e   c h a n g e d .   T h e   v a l u e   o f   s p e c . l o a d B a l a n c e r C l a s s   m u s t   b e   a   l a b e l - s t y l e   i d e n t i f i e r ,   w i t h   a n   o p t i o n a l   p r e f i x   s u c h   a s   " i n t e r n a l - v i p "   o r   " e x a m p l e . c o m / i n t e r n a l - v i p " .   U n p r e f i x e d   n a m e s   a r e   r e s e r v e d   f o r   e n d - u s e r s .


Question: What is Load balancer IP address mode?

Answer: F o r   a   S e r v i c e   o f   t y p e :   L o a d B a l a n c e r ,   a   c o n t r o l l e r   c a n   s e t   . s t a t u s . l o a d B a l a n c e r . i n g r e s s . i p M o d e .   T h e   . s t a t u s . l o a d B a l a n c e r . i n g r e s s . i p M o d e   s p e c i f i e s   h o w   t h e   l o a d - b a l a n c e r   I P   b e h a v e s .   I t   m a y   b e   s p e c i f i e d   o n l y   w h e n   t h e   . s t a t u s . l o a d B a l a n c e r . i n g r e s s . i p   f i e l d   i s   a l s o   s p e c i f i e d .   T h e r e   a r e   t w o   p o s s i b l e   v a l u e s   f o r   . s t a t u s . l o a d B a l a n c e r . i n g r e s s . i p M o d e :   " V I P "   a n d   " P r o x y " .   T h e   d e f a u l t   v a l u e   i s   " V I P "   m e a n i n g   t h a t   t r a f f i c   i s   d e l i v e r e d   t o   t h e   n o d e   w i t h   t h e   d e s t i n a t i o n   s e t   t o   t h e   l o a d - b a l a n c e r ' s   I P   a n d   p o r t .   T h e r e   a r e   t w o   c a s e s   w h e n   s e t t i n g   t h i s   t o   " P r o x y " ,   d e p e n d i n g   o n   h o w   t h e   l o a d - b a l a n c e r   f r o m   t h e   c l o u d   p r o v i d e r   d e l i v e r s   t h e   t r a f f i c s :   I f   t h e   t r a f f i c   i s   d e l i v e r e d   t o   t h e   n o d e   t h e n   D N A T e d   t o   t h e   p o d ,   t h e   d e s t i n a t i o n   w o u l d   b e   s e t   t o   t h e   n o d e ' s   I P   a n d   n o d e   p o r t ; I f   t h e   t r a f f i c   i s   d e l i v e r e d   d i r e c t l y   t o   t h e   p o d ,   t h e   d e s t i n a t i o n   w o u l d   b e   s e t   t o   t h e   p o d ' s   I P   a n d   p o r t .   S e r v i c e   i m p l e m e n t a t i o n s   m a y   u s e   t h i s   i n f o r m a t i o n   t o   a d j u s t   t r a f f i c   r o u t i n g .


Question: What is Internal load balancer?

Answer: I n   a   m i x e d   e n v i r o n m e n t   i t   i s   s o m e t i m e s   n e c e s s a r y   t o   r o u t e   t r a f f i c   f r o m   S e r v i c e s   i n s i d e   t h e   s a m e   ( v i r t u a l )   n e t w o r k   a d d r e s s   b l o c k .   I n   a   s p l i t - h o r i z o n   D N S   e n v i r o n m e n t   y o u   w o u l d   n e e d   t w o   S e r v i c e s   t o   b e   a b l e   t o   r o u t e   b o t h   e x t e r n a l   a n d   i n t e r n a l   t r a f f i c   t o   y o u r   e n d p o i n t s .   T o   s e t   a n   i n t e r n a l   l o a d   b a l a n c e r ,   a d d   o n e   o f   t h e   f o l l o w i n g   a n n o t a t i o n s   t o   y o u r   S e r v i c e   d e p e n d i n g   o n   t h e   c l o u d   s e r v i c e   p r o v i d e r   y o u ' r e   u s i n g :   S e l e c t   o n e   o f   t h e   t a b s .   S e l e c t   o n e   o f   t h e   t a b s .   m e t a d a t a :   n a m e :   m y - s e r v i c e   a n n o t a t i o n s :   n e t w o r k i n g . g k e . i o / l o a d - b a l a n c e r - t y p e :   " I n t e r n a l "   m e t a d a t a :   n a m e :   m y - s e r v i c e   a n n o t a t i o n s :   n e t w o r k i n g . g k e . i o / l o a d - b a l a n c e r - t y p e :   " I n t e r n a l "   m e t a d a t a :   n a m e :   m y - s e r v i c e   a n n o t a t i o n s :   s e r v i c e . b e t a . k u b e r n e t e s . i o / a w s - l o a d - b a l a n c e r - i n t e r n a l :   " t r u e "   m e t a d a t a :   n a m e :   m y - s e r v i c e   a n n o t a t i o n s :   s e r v i c e . b e t a . k u b e r n e t e s . i o / a w s - l o a d - b a l a n c e r - i n t e r n a l :   " t r u e "   m e t a d a t a :   n a m e :   m y - s e r v i c e   a n n o t a t i o n s :   s e r v i c e . b e t a . k u b e r n e t e s . i o / a z u r e - l o a d - b a l a n c e r - i n t e r n a l :   " t r u e "   m e t a d a t a :   n a m e :   m y - s e r v i c e   a n n o t a t i o n s :   s e r v i c e . b e t a . k u b e r n


Question: What is type: ExternalName?

Answer: S e r v i c e s   o f   t y p e   E x t e r n a l N a m e   m a p   a   S e r v i c e   t o   a   D N S   n a m e ,   n o t   t o   a   t y p i c a l   s e l e c t o r   s u c h   a s   m y - s e r v i c e   o r   c a s s a n d r a .   Y o u   s p e c i f y   t h e s e   S e r v i c e s   w i t h   t h e   s p e c . e x t e r n a l N a m e   p a r a m e t e r .   T h i s   S e r v i c e   d e f i n i t i o n ,   f o r   e x a m p l e ,   m a p s   t h e   m y - s e r v i c e   S e r v i c e   i n   t h e   p r o d   n a m e s p a c e   t o   m y . d a t a b a s e . e x a m p l e . c o m :   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   m y - s e r v i c e   n a m e s p a c e :   p r o d   s p e c :   t y p e :   E x t e r n a l N a m e   e x t e r n a l N a m e :   m y . d a t a b a s e . e x a m p l e . c o m


Question: What is Note:?

Answer: A   S e r v i c e   o f   t y p e :   E x t e r n a l N a m e   a c c e p t s   a n   I P v 4   a d d r e s s   s t r i n g ,   b u t   t r e a t s   t h a t   s t r i n g   a s   a   D N S   n a m e   c o m p r i s e d   o f   d i g i t s ,   n o t   a s   a n   I P   a d d r e s s   ( t h e   i n t e r n e t   d o e s   n o t   h o w e v e r   a l l o w   s u c h   n a m e s   i n   D N S ) .   S e r v i c e s   w i t h   e x t e r n a l   n a m e s   t h a t   r e s e m b l e   I P v 4   a d d r e s s e s   a r e   n o t   r e s o l v e d   b y   D N S   s e r v e r s .   I f   y o u   w a n t   t o   m a p   a   S e r v i c e   d i r e c t l y   t o   a   s p e c i f i c   I P   a d d r e s s ,   c o n s i d e r   u s i n g   h e a d l e s s   S e r v i c e s .   W h e n   l o o k i n g   u p   t h e   h o s t   m y - s e r v i c e . p r o d . s v c . c l u s t e r . l o c a l ,   t h e   c l u s t e r   D N S   S e r v i c e   r e t u r n s   a   C N A M E   r e c o r d   w i t h   t h e   v a l u e   m y . d a t a b a s e . e x a m p l e . c o m .   A c c e s s i n g   m y - s e r v i c e   w o r k s   i n   t h e   s a m e   w a y   a s   o t h e r   S e r v i c e s   b u t   w i t h   t h e   c r u c i a l   d i f f e r e n c e   t h a t   r e d i r e c t i o n   h a p p e n s   a t   t h e   D N S   l e v e l   r a t h e r   t h a n   v i a   p r o x y i n g   o r   f o r w a r d i n g .   S h o u l d   y o u   l a t e r   d e c i d e   t o   m o v e   y o u r   d a t a b a s e   i n t o   y o u r   c l u s t e r ,   y o u   c a n   s t a r t   i t s   P o d s ,   a d d   a p p r o p r i a t e   s e l e c t o r s   o r   e n d p o i n t s ,   a n d   c h a n g e   t h e   S e r v i c e ' s   t y p e .


Question: What is Caution:?

Answer: Y o u   m a y   h a v e   t r o u b l e   u s i n g   E x t e r n a l N a m e   f o r   s o m e   c o m m o n   p r o t o c o l s ,   i n c l u d i n g   H T T P   a n d   H T T P S .   I f   y o u   u s e   E x t e r n a l N a m e   t h e n   t h e   h o s t n a m e   u s e d   b y   c l i e n t s   i n s i d e   y o u r   c l u s t e r   i s   d i f f e r e n t   f r o m   t h e   n a m e   t h a t   t h e   E x t e r n a l N a m e   r e f e r e n c e s .   F o r   p r o t o c o l s   t h a t   u s e   h o s t n a m e s   t h i s   d i f f e r e n c e   m a y   l e a d   t o   e r r o r s   o r   u n e x p e c t e d   r e s p o n s e s .   H T T P   r e q u e s t s   w i l l   h a v e   a   H o s t :   h e a d e r   t h a t   t h e   o r i g i n   s e r v e r   d o e s   n o t   r e c o g n i z e ;   T L S   s e r v e r s   w i l l   n o t   b e   a b l e   t o   p r o v i d e   a   c e r t i f i c a t e   m a t c h i n g   t h e   h o s t n a m e   t h a t   t h e   c l i e n t   c o n n e c t e d   t o .


Question: What is Headless Services?

Answer: S o m e t i m e s   y o u   d o n ' t   n e e d   l o a d - b a l a n c i n g   a n d   a   s i n g l e   S e r v i c e   I P .   I n   t h i s   c a s e ,   y o u   c a n   c r e a t e   w h a t   a r e   t e r m e d   h e a d l e s s   S e r v i c e s ,   b y   e x p l i c i t l y   s p e c i f y i n g   " N o n e "   f o r   t h e   c l u s t e r   I P   a d d r e s s   ( . s p e c . c l u s t e r I P ) .   Y o u   c a n   u s e   a   h e a d l e s s   S e r v i c e   t o   i n t e r f a c e   w i t h   o t h e r   s e r v i c e   d i s c o v e r y   m e c h a n i s m s ,   w i t h o u t   b e i n g   t i e d   t o   K u b e r n e t e s '   i m p l e m e n t a t i o n .   F o r   h e a d l e s s   S e r v i c e s ,   a   c l u s t e r   I P   i s   n o t   a l l o c a t e d ,   k u b e - p r o x y   d o e s   n o t   h a n d l e   t h e s e   S e r v i c e s ,   a n d   t h e r e   i s   n o   l o a d   b a l a n c i n g   o r   p r o x y i n g   d o n e   b y   t h e   p l a t f o r m   f o r   t h e m .   A   h e a d l e s s   S e r v i c e   a l l o w s   a   c l i e n t   t o   c o n n e c t   t o   w h i c h e v e r   P o d   i t   p r e f e r s ,   d i r e c t l y .   S e r v i c e s   t h a t   a r e   h e a d l e s s   d o n ' t   c o n f i g u r e   r o u t e s   a n d   p a c k e t   f o r w a r d i n g   u s i n g   v i r t u a l   I P   a d d r e s s e s   a n d   p r o x i e s ;   i n s t e a d ,   h e a d l e s s   S e r v i c e s   r e p o r t   t h e   e n d p o i n t   I P   a d d r e s s e s   o f   t h e   i n d i v i d u a l   p o d s   v i a   i n t e r n a l   D N S   r e c o r d s ,   s e r v e d   t h r o u g h   t h e   c l u s t e r ' s   D N S   s e r v i c e .   T o   d e f i n e   a   h e a d l e s s   S e r v i c e ,   y o u   m a k e   a   S e r v i c e   w i t h   . s p e c . t y p e   s e t   t o   C l u s t e r I P   ( w h i c h   i s   a l s o   t h e   d e f a u l t   f o r   t y p e ) ,   a n d   y o u   a d d i t i o n a l l


Question: What is With selectors?

Answer: F o r   h e a d l e s s   S e r v i c e s   t h a t   d e f i n e   s e l e c t o r s ,   t h e   e n d p o i n t s   c o n t r o l l e r   c r e a t e s   E n d p o i n t S l i c e s   i n   t h e   K u b e r n e t e s   A P I ,   a n d   m o d i f i e s   t h e   D N S   c o n f i g u r a t i o n   t o   r e t u r n   A   o r   A A A A   r e c o r d s   ( I P v 4   o r   I P v 6   a d d r e s s e s )   t h a t   p o i n t   d i r e c t l y   t o   t h e   P o d s   b a c k i n g   t h e   S e r v i c e .


Question: What is Without selectors?

Answer: F o r   h e a d l e s s   S e r v i c e s   t h a t   d o   n o t   d e f i n e   s e l e c t o r s ,   t h e   c o n t r o l   p l a n e   d o e s   n o t   c r e a t e   E n d p o i n t S l i c e   o b j e c t s .   H o w e v e r ,   t h e   D N S   s y s t e m   l o o k s   f o r   a n d   c o n f i g u r e s   e i t h e r :   D N S   C N A M E   r e c o r d s   f o r   t y p e :   E x t e r n a l N a m e   S e r v i c e s . D N S   A   /   A A A A   r e c o r d s   f o r   a l l   I P   a d d r e s s e s   o f   t h e   S e r v i c e ' s   r e a d y   e n d p o i n t s ,   f o r   a l l   S e r v i c e   t y p e s   o t h e r   t h a n   E x t e r n a l N a m e . F o r   I P v 4   e n d p o i n t s ,   t h e   D N S   s y s t e m   c r e a t e s   A   r e c o r d s . F o r   I P v 6   e n d p o i n t s ,   t h e   D N S   s y s t e m   c r e a t e s   A A A A   r e c o r d s .   F o r   I P v 4   e n d p o i n t s ,   t h e   D N S   s y s t e m   c r e a t e s   A   r e c o r d s . F o r   I P v 6   e n d p o i n t s ,   t h e   D N S   s y s t e m   c r e a t e s   A A A A   r e c o r d s .   W h e n   y o u   d e f i n e   a   h e a d l e s s   S e r v i c e   w i t h o u t   a   s e l e c t o r ,   t h e   p o r t   m u s t   m a t c h   t h e   t a r g e t P o r t .


Question: What is Discovering services?

Answer: F o r   c l i e n t s   r u n n i n g   i n s i d e   y o u r   c l u s t e r ,   K u b e r n e t e s   s u p p o r t s   t w o   p r i m a r y   m o d e s   o f   f i n d i n g   a   S e r v i c e :   e n v i r o n m e n t   v a r i a b l e s   a n d   D N S .


Question: What is Environment variables?

Answer: W h e n   a   P o d   i s   r u n   o n   a   N o d e ,   t h e   k u b e l e t   a d d s   a   s e t   o f   e n v i r o n m e n t   v a r i a b l e s   f o r   e a c h   a c t i v e   S e r v i c e .   I t   a d d s   { S V C N A M E } _ S E R V I C E _ H O S T   a n d   { S V C N A M E } _ S E R V I C E _ P O R T   v a r i a b l e s ,   w h e r e   t h e   S e r v i c e   n a m e   i s   u p p e r - c a s e d   a n d   d a s h e s   a r e   c o n v e r t e d   t o   u n d e r s c o r e s .   F o r   e x a m p l e ,   t h e   S e r v i c e   r e d i s - p r i m a r y   w h i c h   e x p o s e s   T C P   p o r t   6 3 7 9   a n d   h a s   b e e n   a l l o c a t e d   c l u s t e r   I P   a d d r e s s   1 0 . 0 . 0 . 1 1 ,   p r o d u c e s   t h e   f o l l o w i n g   e n v i r o n m e n t   v a r i a b l e s :   R E D I S _ P R I M A R Y _ S E R V I C E _ H O S T = 1 0 . 0 . 0 . 1 1   R E D I S _ P R I M A R Y _ S E R V I C E _ P O R T = 6 3 7 9   R E D I S _ P R I M A R Y _ P O R T = t c p : / / 1 0 . 0 . 0 . 1 1 : 6 3 7 9   R E D I S _ P R I M A R Y _ P O R T _ 6 3 7 9 _ T C P = t c p : / / 1 0 . 0 . 0 . 1 1 : 6 3 7 9   R E D I S _ P R I M A R Y _ P O R T _ 6 3 7 9 _ T C P _ P R O T O = t c p   R E D I S _ P R I M A R Y _ P O R T _ 6 3 7 9 _ T C P _ P O R T = 6 3 7 9   R E D I S _ P R I M A R Y _ P O R T _ 6 3 7 9 _ T C P _ A D D R = 1 0 . 0 . 0 . 1 1


Question: What is Note:?

Answer: W h e n   y o u   h a v e   a   P o d   t h a t   n e e d s   t o   a c c e s s   a   S e r v i c e ,   a n d   y o u   a r e   u s i n g   t h e   e n v i r o n m e n t   v a r i a b l e   m e t h o d   t o   p u b l i s h   t h e   p o r t   a n d   c l u s t e r   I P   t o   t h e   c l i e n t   P o d s ,   y o u   m u s t   c r e a t e   t h e   S e r v i c e   b e f o r e   t h e   c l i e n t   P o d s   c o m e   i n t o   e x i s t e n c e .   O t h e r w i s e ,   t h o s e   c l i e n t   P o d s   w o n ' t   h a v e   t h e i r   e n v i r o n m e n t   v a r i a b l e s   p o p u l a t e d .   I f   y o u   o n l y   u s e   D N S   t o   d i s c o v e r   t h e   c l u s t e r   I P   f o r   a   S e r v i c e ,   y o u   d o n ' t   n e e d   t o   w o r r y   a b o u t   t h i s   o r d e r i n g   i s s u e .   K u b e r n e t e s   a l s o   s u p p o r t s   a n d   p r o v i d e s   v a r i a b l e s   t h a t   a r e   c o m p a t i b l e   w i t h   D o c k e r   E n g i n e ' s   " l e g a c y   c o n t a i n e r   l i n k s "   f e a t u r e .   Y o u   c a n   r e a d   m a k e L i n k V a r i a b l e s   t o   s e e   h o w   t h i s   i s   i m p l e m e n t e d   i n   K u b e r n e t e s .


Question: What is DNS?

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


Question: What is Virtual IP addressing mechanism?

Answer: R e a d   V i r t u a l   I P s   a n d   S e r v i c e   P r o x i e s   e x p l a i n s   t h e   m e c h a n i s m   K u b e r n e t e s   p r o v i d e s   t o   e x p o s e   a   S e r v i c e   w i t h   a   v i r t u a l   I P   a d d r e s s .


Question: What is Traffic policies?

Answer: Y o u   c a n   s e t   t h e   . s p e c . i n t e r n a l T r a f f i c P o l i c y   a n d   . s p e c . e x t e r n a l T r a f f i c P o l i c y   f i e l d s   t o   c o n t r o l   h o w   K u b e r n e t e s   r o u t e s   t r a f f i c   t o   h e a l t h y   ( “ r e a d y ” )   b a c k e n d s .   S e e   T r a f f i c   P o l i c i e s   f o r   m o r e   d e t a i l s .


Question: What is Traffic distribution?

Answer: T h e   . s p e c . t r a f f i c D i s t r i b u t i o n   f i e l d   p r o v i d e s   a n o t h e r   w a y   t o   i n f l u e n c e   t r a f f i c   r o u t i n g   w i t h i n   a   K u b e r n e t e s   S e r v i c e .   W h i l e   t r a f f i c   p o l i c i e s   f o c u s   o n   s t r i c t   s e m a n t i c   g u a r a n t e e s ,   t r a f f i c   d i s t r i b u t i o n   a l l o w s   y o u   t o   e x p r e s s   p r e f e r e n c e s   ( s u c h   a s   r o u t i n g   t o   t o p o l o g i c a l l y   c l o s e r   e n d p o i n t s ) .   T h i s   c a n   h e l p   o p t i m i z e   f o r   p e r f o r m a n c e ,   c o s t ,   o r   r e l i a b i l i t y .   I n   K u b e r n e t e s   1 . 3 4 ,   t h e   f o l l o w i n g   f i e l d   v a l u e   i s   s u p p o r t e d :   I n   K u b e r n e t e s   1 . 3 4 ,   t w o   a d d i t i o n a l   v a l u e s   a r e   a v a i l a b l e   ( u n l e s s   t h e   P r e f e r S a m e T r a f f i c D i s t r i b u t i o n   f e a t u r e   g a t e   i s   d i s a b l e d ) :   I f   t h e   f i e l d   i s   n o t   s e t ,   t h e   i m p l e m e n t a t i o n   w i l l   a p p l y   i t s   d e f a u l t   r o u t i n g   s t r a t e g y .   S e e   T r a f f i c   D i s t r i b u t i o n   f o r   m o r e   d e t a i l s


Question: What is Session stickiness?

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


Question: What is External IPs?

Answer: I f   t h e r e   a r e   e x t e r n a l   I P s   t h a t   r o u t e   t o   o n e   o r   m o r e   c l u s t e r   n o d e s ,   K u b e r n e t e s   S e r v i c e s   c a n   b e   e x p o s e d   o n   t h o s e   e x t e r n a l I P s .   W h e n   n e t w o r k   t r a f f i c   a r r i v e s   i n t o   t h e   c l u s t e r ,   w i t h   t h e   e x t e r n a l   I P   ( a s   d e s t i n a t i o n   I P )   a n d   t h e   p o r t   m a t c h i n g   t h a t   S e r v i c e ,   r u l e s   a n d   r o u t e s   t h a t   K u b e r n e t e s   h a s   c o n f i g u r e d   e n s u r e   t h a t   t h e   t r a f f i c   i s   r o u t e d   t o   o n e   o f   t h e   e n d p o i n t s   f o r   t h a t   S e r v i c e .   W h e n   y o u   d e f i n e   a   S e r v i c e ,   y o u   c a n   s p e c i f y   e x t e r n a l I P s   f o r   a n y   s e r v i c e   t y p e .   I n   t h e   e x a m p l e   b e l o w ,   t h e   S e r v i c e   n a m e d   " m y - s e r v i c e "   c a n   b e   a c c e s s e d   b y   c l i e n t s   u s i n g   T C P ,   o n   " 1 9 8 . 5 1 . 1 0 0 . 3 2 : 8 0 "   ( c a l c u l a t e d   f r o m   . s p e c . e x t e r n a l I P s [ ]   a n d   . s p e c . p o r t s [ ] . p o r t ) .   a p i V e r s i o n :   v 1   k i n d :   S e r v i c e   m e t a d a t a :   n a m e :   m y - s e r v i c e   s p e c :   s e l e c t o r :   a p p . k u b e r n e t e s . i o / n a m e :   M y A p p   p o r t s :   -   n a m e :   h t t p   p r o t o c o l :   T C P   p o r t :   8 0   t a r g e t P o r t :   4 9 1 5 2   e x t e r n a l I P s :   -   1 9 8 . 5 1 . 1 0 0 . 3 2


Question: What is API Object?

Answer: S e r v i c e   i s   a   t o p - l e v e l   r e s o u r c e   i n   t h e   K u b e r n e t e s   R E S T   A P I .   Y o u   c a n   f i n d   m o r e   d e t a i l s   a b o u t   t h e   S e r v i c e   A P I   o b j e c t .


Question: What is What's next?

Answer: L e a r n   m o r e   a b o u t   S e r v i c e s   a n d   h o w   t h e y   f i t   i n t o   K u b e r n e t e s :   F o l l o w   t h e   C o n n e c t i n g   A p p l i c a t i o n s   w i t h   S e r v i c e s   t u t o r i a l . R e a d   a b o u t   I n g r e s s ,   w h i c h   e x p o s e s   H T T P   a n d   H T T P S   r o u t e s   f r o m   o u t s i d e   t h e   c l u s t e r   t o   S e r v i c e s   w i t h i n   y o u r   c l u s t e r . R e a d   a b o u t   G a t e w a y ,   a n   e x t e n s i o n   t o   K u b e r n e t e s   t h a t   p r o v i d e s   m o r e   f l e x i b i l i t y   t h a n   I n g r e s s .   F o r   m o r e   c o n t e x t ,   r e a d   t h e   f o l l o w i n g :   V i r t u a l   I P s   a n d   S e r v i c e   P r o x i e s E n d p o i n t S l i c e s S e r v i c e   A P I   r e f e r e n c e E n d p o i n t S l i c e   A P I   r e f e r e n c e E n d p o i n t   A P I   r e f e r e n c e   ( l e g a c y )


Question: What is kubectl config rename-context?

Answer: kubectl config rename-contextSynopsisRenames a context from the kubeconfig file.CONTEXT_NAME is the context name that you want to change.NEW_NAME is the new name you want to set.Note: If the context being renamed is the 'current-context', this field will also be updated.kubectl config rename-context CONTEXT_NAME NEW_NAME Examples # Rename the context 'old-name' to 'new-name' in your kubeconfig file kubectl config rename-context old-name new-name Options-h, --helphelp for rename-contextParent 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 stringuse a particular kubeconfig file--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,


Question: How does kubectl config rename-context work?

Answer: kubectl config rename-contextSynopsisRenames a context from the kubeconfig file.CONTEXT_NAME is the context name that you want to change.NEW_NAME is the new name you want to set.Note: If the context being renamed is the 'current-context', this field will also be updated.kubectl config rename-context CONTEXT_NAME NEW_NAME Examples # Rename the context 'old-name' to 'new-name' in your kubeconfig file kubectl config rename-context old-name new-name Options-h, --helphelp for rename-contextParent 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 stringuse a particular kubeconfig file--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,


Question: When would you use kubectl config rename-context?

Answer: kubectl config rename-contextSynopsisRenames a context from the kubeconfig file.CONTEXT_NAME is the context name that you want to change.NEW_NAME is the new name you want to set.Note: If the context being renamed is the 'current-context', this field will also be updated.kubectl config rename-context CONTEXT_NAME NEW_NAME Examples # Rename the context 'old-name' to 'new-name' in your kubeconfig file kubectl config rename-context old-name new-name Options-h, --helphelp for rename-contextParent 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 stringuse a particular kubeconfig file--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,


Question: What are the benefits of kubectl config rename-context?

Answer: kubectl config rename-contextSynopsisRenames a context from the kubeconfig file.CONTEXT_NAME is the context name that you want to change.NEW_NAME is the new name you want to set.Note: If the context being renamed is the 'current-context', this field will also be updated.kubectl config rename-context CONTEXT_NAME NEW_NAME Examples # Rename the context 'old-name' to 'new-name' in your kubeconfig file kubectl config rename-context old-name new-name Options-h, --helphelp for rename-contextParent 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 stringuse a particular kubeconfig file--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,


Question: What is Synopsis?

Answer: R e n a m e s   a   c o n t e x t   f r o m   t h e   k u b e c o n f i g   f i l e .   C O N T E X T _ N A M E   i s   t h e   c o n t e x t   n a m e   t h a t   y o u   w a n t   t o   c h a n g e .   N E W _ N A M E   i s   t h e   n e w   n a m e   y o u   w a n t   t o   s e t .   N o t e :   I f   t h e   c o n t e x t   b e i n g   r e n a m e d   i s   t h e   ' c u r r e n t - c o n t e x t ' ,   t h i s   f i e l d   w i l l   a l s o   b e   u p d a t e d .   k u b e c t l   c o n f i g   r e n a m e - c o n t e x t   C O N T E X T _ N A M E   N E W _ N A M E


Question: What is Examples?

Answer: #   R e n a m e   t h e   c o n t e x t   ' o l d - n a m e '   t o   ' n e w - n a m e '   i n   y o u r   k u b e c o n f i g   f i l e   k u b e c t l   c o n f i g   r e n a m e - c o n t e x t   o l d - n a m e   n e w - n a m e


Question: What is Options?

Answer: h e l p   f o r   r e n a m e - c o n t e x t