Question: What are the benefits of Building a Basic DaemonSet?

Answer: Building a Basic DaemonSetThis page demonstrates how to build a basic DaemonSet that runs a Pod on every node in a Kubernetes cluster. It covers a simple use case of mounting a file from the host, logging its contents using an init container, and utilizing a pause container.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 KubernetesA Kubernetes cluster with at least two nodes (one control plane node and one worker node) to demonstrate the behavior of DaemonSets.Define the DaemonSetIn this task, a basic DaemonSet is created which ensures that the copy of a Pod is scheduled on every node. The Pod will use an init container to read and log the contents of /etc/machine-id from the host, while the main container will be a pause container, which keeps the Pod running.application/basic-daemonset.yaml apiVersion: apps/v1 kind: DaemonSet metadata: name: example-daemonset spec: selector: matchLabels: app.kubernetes.io/name: example template: metadata: labels: app.kubernetes.io/name: example spec: containers: - name: pause image: registry.k8s.io/pause initContainers: - name: log-machine-id image: busybox:1.37 command: ['sh', '-c', 'cat /etc/machine-id > /var/log/machine-id.log'] volumeMounts: - name: machine-id mountPath: /etc/machine-id readOnly: true - name: log-dir mountPath: /var/log volumes: - name: machine-id hostPath: path: /etc/machine-id type: File - name: log-dir hostPath: path: /var/logCreate a DaemonSet based on the (YAML) manifest:kubectl apply -f https://k8s.io/examples/application/basic-daemonset.yaml Once applied, you can verify that the DaemonSet is running a Pod on every node in the cluster:kubectl get pods -o wide The output will list one Pod per node, similar to:NAME READY STATUS RESTARTS AGE IP NODE example-daemonset-xxxxx 1/1 Running 0 5m x.x.x.x node-1 example-daemonset-yyyyy 1/1 Running 0 5m x.x.x.x node-2 You can inspect the contents of the logged /etc/machine-id file by checking the log directory mounted from the host:kubectl exec <pod-name> -- cat /var/log/machine-id.log Where <pod-name> is the name of one of your Pods.Cleaning upTo delete the DaemonSet, run this command:kubectl delete --cascade=foreground --ignore-not-found --now daemonsets/example-daemonset This simple DaemonSet example introduces key components like init containers and host path volumes, which can be expanded upon for more advanced use cases. For more details refer to DaemonSet.What's nextSee Performing a rolling update on a DaemonSetSee Creating a DaemonSet to adopt existing DaemonSet pods


Question: What is Building a Basic DaemonSet?

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


Question: What is Before you begin?

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


Question: What is Define the DaemonSet?

Answer: I n   t h i s   t a s k ,   a   b a s i c   D a e m o n S e t   i s   c r e a t e d   w h i c h   e n s u r e s   t h a t   t h e   c o p y   o f   a   P o d   i s   s c h e d u l e d   o n   e v e r y   n o d e .   T h e   P o d   w i l l   u s e   a n   i n i t   c o n t a i n e r   t o   r e a d   a n d   l o g   t h e   c o n t e n t s   o f   / e t c / m a c h i n e - i d   f r o m   t h e   h o s t ,   w h i l e   t h e   m a i n   c o n t a i n e r   w i l l   b e   a   p a u s e   c o n t a i n e r ,   w h i c h   k e e p s   t h e   P o d   r u n n i n g .   a p i V e r s i o n :   a p p s / v 1   k i n d :   D a e m o n S e t   m e t a d a t a :   n a m e :   e x a m p l e - d a e m o n s e t   s p e c :   s e l e c t o r :   m a t c h 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 :   e x a m p l e   t e m p l a t e :   m e t a d a t a :   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 :   e x a m p l e   s p e c :   c o n t a i n e r s :   -   n a m e :   p a u s e   i m a g e :   r e g i s t r y . k 8 s . i o / p a u s e   i n i t C o n t a i n e r s :   -   n a m e :   l o g - m a c h i n e - i d   i m a g e :   b u s y b o x : 1 . 3 7   c o m m a n d :   [ ' s h ' ,   ' - c ' ,   ' c a t   / e t c / m a c h i n e - i d   >   / v a r / l o g / m a c h i n e - i d . l o g ' ]   v o l u m e M o u n t s :   -   n a m e :   m a c h i n e - i d   m o u n t P a t h :   / e t c / m a c h i n e - i d   r e a d O n l y :   t r u e   -   n a m e :   l o g - d i r   m o u n t P a t h :   / v a r / l o g   v o l u m e s :   -   n a m e :   m a c h i n e - i d   h o s t P a t h :   p a t h :   / e t c / m a c h i n e - i d   t y p e :   F i l e   -   n a m e :   l o g - d i r   h o s t P a t h :   p a t h :   / v a r / l o g   C r e a t e   a   D a e m o n S e t   b a s e d   o n   t h e   ( Y A M L )   m a n i f e s t : k u b e c t l   a p p l y   - f   h t t p s : / / k 8 s . i o / e x a m p l e s / a p p l i c a t i o n / b a s i c - d


Question: What is Cleaning up?

Answer: T o   d e l e t e   t h e   D a e m o n S e t ,   r u n   t h i s   c o m m a n d :   k u b e c t l   d e l e t e   - - c a s c a d e = f o r e g r o u n d   - - i g n o r e - n o t - f o u n d   - - n o w   d a e m o n s e t s / e x a m p l e - d a e m o n s e t   T h i s   s i m p l e   D a e m o n S e t   e x a m p l e   i n t r o d u c e s   k e y   c o m p o n e n t s   l i k e   i n i t   c o n t a i n e r s   a n d   h o s t   p a t h   v o l u m e s ,   w h i c h   c a n   b e   e x p a n d e d   u p o n   f o r   m o r e   a d v a n c e d   u s e   c a s e s .   F o r   m o r e   d e t a i l s   r e f e r   t o   D a e m o n S e t .


Question: What is What's next?

Answer: S e e   P e r f o r m i n g   a   r o l l i n g   u p d a t e   o n   a   D a e m o n S e t S e e   C r e a t i n g   a   D a e m o n S e t   t o   a d o p t   e x i s t i n g   D a e m o n S e t   p o d s


Question: What is Issue Wranglers?

Answer: Issue WranglersAlongside the PR Wrangler, formal approvers, reviewers and members of SIG Docs take week-long shifts triaging and categorising issues for the repository.DutiesEach day in a week-long shift the Issue Wrangler will be responsible for:Triaging and tagging incoming issues daily. See Triage and categorize issues for guidelines on how SIG Docs uses metadata.Keeping an eye on stale & rotten issues within the kubernetes/website repository.Maintenance of the Issues board.RequirementsMust be an active member of the Kubernetes organization.A minimum of 15 non-trivial contributions to Kubernetes (of which a certain amount should be directed towards kubernetes/website).Performing the role in an informal capacity already.Helpful Prow commands for wranglersBelow are some commonly used commands for Issue Wranglers:# reopen an issue /reopen # transfer issues that don't fit in k/website to another repository /transfer[-issue] # change the state of rotten issues /remove-lifecycle rotten # change the state of stale issues /remove-lifecycle stale # assign sig to an issue /sig <sig_name> # add specific area /area <area_name> # for beginner friendly issues /good-first-issue # issues that needs help /help wanted # tagging issue as support specific /kind support # to accept triaging for an issue /triage accepted # closing an issue we won't be working on and haven't fixed yet /close not-planned To find more Prow commands, refer to the Command Help documentation.When to close IssuesFor an open source project to succeed, good issue management is crucial. But it is also critical to resolve issues in order to maintain the repository and communicate clearly with contributors and users.Close issues when:A similar issue is reported more than once. You will first need to tag it as /triage duplicate; link it to the main issue & then close it. It is also advisable to direct the users to the original issue.It is very difficult to understand and address the issue presented by the author with the information provided. However, encourage the user to provide more details or reopen the issue if they can reproduce it later.The same functionality is implemented elsewhere. One can close this issue and direct user to the appropriate place.The reported issue is not currently planned or aligned with the project's goals.If the issue appears to be spam and is clearly unrelated.If the issue is related to an external limitation or dependency and is beyond the control of the project.To close an issue, leave a /close comment on the issue.


Question: How does Issue Wranglers work?

Answer: Issue WranglersAlongside the PR Wrangler, formal approvers, reviewers and members of SIG Docs take week-long shifts triaging and categorising issues for the repository.DutiesEach day in a week-long shift the Issue Wrangler will be responsible for:Triaging and tagging incoming issues daily. See Triage and categorize issues for guidelines on how SIG Docs uses metadata.Keeping an eye on stale & rotten issues within the kubernetes/website repository.Maintenance of the Issues board.RequirementsMust be an active member of the Kubernetes organization.A minimum of 15 non-trivial contributions to Kubernetes (of which a certain amount should be directed towards kubernetes/website).Performing the role in an informal capacity already.Helpful Prow commands for wranglersBelow are some commonly used commands for Issue Wranglers:# reopen an issue /reopen # transfer issues that don't fit in k/website to another repository /transfer[-issue] # change the state of rotten issues /remove-lifecycle rotten # change the state of stale issues /remove-lifecycle stale # assign sig to an issue /sig <sig_name> # add specific area /area <area_name> # for beginner friendly issues /good-first-issue # issues that needs help /help wanted # tagging issue as support specific /kind support # to accept triaging for an issue /triage accepted # closing an issue we won't be working on and haven't fixed yet /close not-planned To find more Prow commands, refer to the Command Help documentation.When to close IssuesFor an open source project to succeed, good issue management is crucial. But it is also critical to resolve issues in order to maintain the repository and communicate clearly with contributors and users.Close issues when:A similar issue is reported more than once. You will first need to tag it as /triage duplicate; link it to the main issue & then close it. It is also advisable to direct the users to the original issue.It is very difficult to understand and address the issue presented by the author with the information provided. However, encourage the user to provide more details or reopen the issue if they can reproduce it later.The same functionality is implemented elsewhere. One can close this issue and direct user to the appropriate place.The reported issue is not currently planned or aligned with the project's goals.If the issue appears to be spam and is clearly unrelated.If the issue is related to an external limitation or dependency and is beyond the control of the project.To close an issue, leave a /close comment on the issue.


Question: When would you use Issue Wranglers?

Answer: Issue WranglersAlongside the PR Wrangler, formal approvers, reviewers and members of SIG Docs take week-long shifts triaging and categorising issues for the repository.DutiesEach day in a week-long shift the Issue Wrangler will be responsible for:Triaging and tagging incoming issues daily. See Triage and categorize issues for guidelines on how SIG Docs uses metadata.Keeping an eye on stale & rotten issues within the kubernetes/website repository.Maintenance of the Issues board.RequirementsMust be an active member of the Kubernetes organization.A minimum of 15 non-trivial contributions to Kubernetes (of which a certain amount should be directed towards kubernetes/website).Performing the role in an informal capacity already.Helpful Prow commands for wranglersBelow are some commonly used commands for Issue Wranglers:# reopen an issue /reopen # transfer issues that don't fit in k/website to another repository /transfer[-issue] # change the state of rotten issues /remove-lifecycle rotten # change the state of stale issues /remove-lifecycle stale # assign sig to an issue /sig <sig_name> # add specific area /area <area_name> # for beginner friendly issues /good-first-issue # issues that needs help /help wanted # tagging issue as support specific /kind support # to accept triaging for an issue /triage accepted # closing an issue we won't be working on and haven't fixed yet /close not-planned To find more Prow commands, refer to the Command Help documentation.When to close IssuesFor an open source project to succeed, good issue management is crucial. But it is also critical to resolve issues in order to maintain the repository and communicate clearly with contributors and users.Close issues when:A similar issue is reported more than once. You will first need to tag it as /triage duplicate; link it to the main issue & then close it. It is also advisable to direct the users to the original issue.It is very difficult to understand and address the issue presented by the author with the information provided. However, encourage the user to provide more details or reopen the issue if they can reproduce it later.The same functionality is implemented elsewhere. One can close this issue and direct user to the appropriate place.The reported issue is not currently planned or aligned with the project's goals.If the issue appears to be spam and is clearly unrelated.If the issue is related to an external limitation or dependency and is beyond the control of the project.To close an issue, leave a /close comment on the issue.


Question: What are the benefits of Issue Wranglers?

Answer: Issue WranglersAlongside the PR Wrangler, formal approvers, reviewers and members of SIG Docs take week-long shifts triaging and categorising issues for the repository.DutiesEach day in a week-long shift the Issue Wrangler will be responsible for:Triaging and tagging incoming issues daily. See Triage and categorize issues for guidelines on how SIG Docs uses metadata.Keeping an eye on stale & rotten issues within the kubernetes/website repository.Maintenance of the Issues board.RequirementsMust be an active member of the Kubernetes organization.A minimum of 15 non-trivial contributions to Kubernetes (of which a certain amount should be directed towards kubernetes/website).Performing the role in an informal capacity already.Helpful Prow commands for wranglersBelow are some commonly used commands for Issue Wranglers:# reopen an issue /reopen # transfer issues that don't fit in k/website to another repository /transfer[-issue] # change the state of rotten issues /remove-lifecycle rotten # change the state of stale issues /remove-lifecycle stale # assign sig to an issue /sig <sig_name> # add specific area /area <area_name> # for beginner friendly issues /good-first-issue # issues that needs help /help wanted # tagging issue as support specific /kind support # to accept triaging for an issue /triage accepted # closing an issue we won't be working on and haven't fixed yet /close not-planned To find more Prow commands, refer to the Command Help documentation.When to close IssuesFor an open source project to succeed, good issue management is crucial. But it is also critical to resolve issues in order to maintain the repository and communicate clearly with contributors and users.Close issues when:A similar issue is reported more than once. You will first need to tag it as /triage duplicate; link it to the main issue & then close it. It is also advisable to direct the users to the original issue.It is very difficult to understand and address the issue presented by the author with the information provided. However, encourage the user to provide more details or reopen the issue if they can reproduce it later.The same functionality is implemented elsewhere. One can close this issue and direct user to the appropriate place.The reported issue is not currently planned or aligned with the project's goals.If the issue appears to be spam and is clearly unrelated.If the issue is related to an external limitation or dependency and is beyond the control of the project.To close an issue, leave a /close comment on the issue.


Question: What is Issue Wranglers?

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


Question: What is Duties?

Answer: E a c h   d a y   i n   a   w e e k - l o n g   s h i f t   t h e   I s s u e   W r a n g l e r   w i l l   b e   r e s p o n s i b l e   f o r :   T r i a g i n g   a n d   t a g g i n g   i n c o m i n g   i s s u e s   d a i l y .   S e e   T r i a g e   a n d   c a t e g o r i z e   i s s u e s   f o r   g u i d e l i n e s   o n   h o w   S I G   D o c s   u s e s   m e t a d a t a . K e e p i n g   a n   e y e   o n   s t a l e   &   r o t t e n   i s s u e s   w i t h i n   t h e   k u b e r n e t e s / w e b s i t e   r e p o s i t o r y . M a i n t e n a n c e   o f   t h e   I s s u e s   b o a r d .


Question: What is Requirements?

Answer: M u s t   b e   a n   a c t i v e   m e m b e r   o f   t h e   K u b e r n e t e s   o r g a n i z a t i o n . A   m i n i m u m   o f   1 5   n o n - t r i v i a l   c o n t r i b u t i o n s   t o   K u b e r n e t e s   ( o f   w h i c h   a   c e r t a i n   a m o u n t   s h o u l d   b e   d i r e c t e d   t o w a r d s   k u b e r n e t e s / w e b s i t e ) . P e r f o r m i n g   t h e   r o l e   i n   a n   i n f o r m a l   c a p a c i t y   a l r e a d y .


Question: What is Helpful Prow commands for wranglers?

Answer: B e l o w   a r e   s o m e   c o m m o n l y   u s e d   c o m m a n d s   f o r   I s s u e   W r a n g l e r s :   #   r e o p e n   a n   i s s u e   / r e o p e n   #   t r a n s f e r   i s s u e s   t h a t   d o n ' t   f i t   i n   k / w e b s i t e   t o   a n o t h e r   r e p o s i t o r y   / t r a n s f e r [ - i s s u e ]   #   c h a n g e   t h e   s t a t e   o f   r o t t e n   i s s u e s   / r e m o v e - l i f e c y c l e   r o t t e n   #   c h a n g e   t h e   s t a t e   o f   s t a l e   i s s u e s   / r e m o v e - l i f e c y c l e   s t a l e   #   a s s i g n   s i g   t o   a n   i s s u e   / s i g   < s i g _ n a m e >   #   a d d   s p e c i f i c   a r e a   / a r e a   < a r e a _ n a m e >   #   f o r   b e g i n n e r   f r i e n d l y   i s s u e s   / g o o d - f i r s t - i s s u e   #   i s s u e s   t h a t   n e e d s   h e l p   / h e l p   w a n t e d   #   t a g g i n g   i s s u e   a s   s u p p o r t   s p e c i f i c   / k i n d   s u p p o r t   #   t o   a c c e p t   t r i a g i n g   f o r   a n   i s s u e   / t r i a g e   a c c e p t e d   #   c l o s i n g   a n   i s s u e   w e   w o n ' t   b e   w o r k i n g   o n   a n d   h a v e n ' t   f i x e d   y e t   / c l o s e   n o t - p l a n n e d   T o   f i n d   m o r e   P r o w   c o m m a n d s ,   r e f e r   t o   t h e   C o m m a n d   H e l p   d o c u m e n t a t i o n .


Question: What is When to close Issues?

Answer: F o r   a n   o p e n   s o u r c e   p r o j e c t   t o   s u c c e e d ,   g o o d   i s s u e   m a n a g e m e n t   i s   c r u c i a l .   B u t   i t   i s   a l s o   c r i t i c a l   t o   r e s o l v e   i s s u e s   i n   o r d e r   t o   m a i n t a i n   t h e   r e p o s i t o r y   a n d   c o m m u n i c a t e   c l e a r l y   w i t h   c o n t r i b u t o r s   a n d   u s e r s .   C l o s e   i s s u e s   w h e n :   A   s i m i l a r   i s s u e   i s   r e p o r t e d   m o r e   t h a n   o n c e .   Y o u   w i l l   f i r s t   n e e d   t o   t a g   i t   a s   / t r i a g e   d u p l i c a t e ;   l i n k   i t   t o   t h e   m a i n   i s s u e   &   t h e n   c l o s e   i t .   I t   i s   a l s o   a d v i s a b l e   t o   d i r e c t   t h e   u s e r s   t o   t h e   o r i g i n a l   i s s u e . I t   i s   v e r y   d i f f i c u l t   t o   u n d e r s t a n d   a n d   a d d r e s s   t h e   i s s u e   p r e s e n t e d   b y   t h e   a u t h o r   w i t h   t h e   i n f o r m a t i o n   p r o v i d e d .   H o w e v e r ,   e n c o u r a g e   t h e   u s e r   t o   p r o v i d e   m o r e   d e t a i l s   o r   r e o p e n   t h e   i s s u e   i f   t h e y   c a n   r e p r o d u c e   i t   l a t e r . T h e   s a m e   f u n c t i o n a l i t y   i s   i m p l e m e n t e d   e l s e w h e r e .   O n e   c a n   c l o s e   t h i s   i s s u e   a n d   d i r e c t   u s e r   t o   t h e   a p p r o p r i a t e   p l a c e . T h e   r e p o r t e d   i s s u e   i s   n o t   c u r r e n t l y   p l a n n e d   o r   a l i g n e d   w i t h   t h e   p r o j e c t ' s   g o a l s . I f   t h e   i s s u e   a p p e a r s   t o   b e   s p a m   a n d   i s   c l e a r l y   u n r e l a t e d . I f   t h e   i s s u e   i s   r e l a t e d   t o   a n   e x t e r n a l   l i m i t a t i o n   o r   d e p e n d e n c y   a n d   i s   b e y o n d   t h e   c o n t r o l   o f   t h e   p r o j e c t .   T o


Question: What is Options for Highly Available Topology?

Answer: Options for Highly Available TopologyThis page explains the two options for configuring the topology of your highly available (HA) Kubernetes clusters.You can set up an HA cluster:With stacked control plane nodes, where etcd nodes are colocated with control plane nodesWith external etcd nodes, where etcd runs on separate nodes from the control planeYou should carefully consider the advantages and disadvantages of each topology before setting up an HA cluster.Note:kubeadm bootstraps the etcd cluster statically. Read the etcd Clustering Guide for more details.Stacked etcd topologyA stacked HA cluster is a topology where the distributed data storage cluster provided by etcd is stacked on top of the cluster formed by the nodes managed by kubeadm that run control plane components.Each control plane node runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. The kube-apiserver is exposed to worker nodes using a load balancer.Each control plane node creates a local etcd member and this etcd member communicates only with the kube-apiserver of this node. The same applies to the local kube-controller-manager and kube-scheduler instances.This topology couples the control planes and etcd members on the same nodes. It is simpler to set up than a cluster with external etcd nodes, and simpler to manage for replication.However, a stacked cluster runs the risk of failed coupling. If one node goes down, both an etcd member and a control plane instance are lost, and redundancy is compromised. You can mitigate this risk by adding more control plane nodes.You should therefore run a minimum of three stacked control plane nodes for an HA cluster.This is the default topology in kubeadm. A local etcd member is created automatically on control plane nodes when using kubeadm init and kubeadm join --control-plane.External etcd topologyAn HA cluster with external etcd is a topology where the distributed data storage cluster provided by etcd is external to the cluster formed by the nodes that run control plane components.Like the stacked etcd topology, each control plane node in an external etcd topology runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. And the kube-apiserver is exposed to worker nodes using a load balancer. However, etcd members run on separate hosts, and each etcd host communicates with the kube-apiserver of each control plane node.This topology decouples the control plane and etcd member. It therefore provides an HA setup where losing a control plane instance or an etcd member has less impact and does not affect the cluster redundancy as much as the stacked HA topology.However, this topology requires twice the number of hosts as the stacked HA topology. A minimum of three hosts for control plane nodes and three hosts for etcd nodes are required for an HA cluster with this topology.What's nextSet up a highly available cluster with kubeadm


Question: How does Options for Highly Available Topology work?

Answer: Options for Highly Available TopologyThis page explains the two options for configuring the topology of your highly available (HA) Kubernetes clusters.You can set up an HA cluster:With stacked control plane nodes, where etcd nodes are colocated with control plane nodesWith external etcd nodes, where etcd runs on separate nodes from the control planeYou should carefully consider the advantages and disadvantages of each topology before setting up an HA cluster.Note:kubeadm bootstraps the etcd cluster statically. Read the etcd Clustering Guide for more details.Stacked etcd topologyA stacked HA cluster is a topology where the distributed data storage cluster provided by etcd is stacked on top of the cluster formed by the nodes managed by kubeadm that run control plane components.Each control plane node runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. The kube-apiserver is exposed to worker nodes using a load balancer.Each control plane node creates a local etcd member and this etcd member communicates only with the kube-apiserver of this node. The same applies to the local kube-controller-manager and kube-scheduler instances.This topology couples the control planes and etcd members on the same nodes. It is simpler to set up than a cluster with external etcd nodes, and simpler to manage for replication.However, a stacked cluster runs the risk of failed coupling. If one node goes down, both an etcd member and a control plane instance are lost, and redundancy is compromised. You can mitigate this risk by adding more control plane nodes.You should therefore run a minimum of three stacked control plane nodes for an HA cluster.This is the default topology in kubeadm. A local etcd member is created automatically on control plane nodes when using kubeadm init and kubeadm join --control-plane.External etcd topologyAn HA cluster with external etcd is a topology where the distributed data storage cluster provided by etcd is external to the cluster formed by the nodes that run control plane components.Like the stacked etcd topology, each control plane node in an external etcd topology runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. And the kube-apiserver is exposed to worker nodes using a load balancer. However, etcd members run on separate hosts, and each etcd host communicates with the kube-apiserver of each control plane node.This topology decouples the control plane and etcd member. It therefore provides an HA setup where losing a control plane instance or an etcd member has less impact and does not affect the cluster redundancy as much as the stacked HA topology.However, this topology requires twice the number of hosts as the stacked HA topology. A minimum of three hosts for control plane nodes and three hosts for etcd nodes are required for an HA cluster with this topology.What's nextSet up a highly available cluster with kubeadm


Question: When would you use Options for Highly Available Topology?

Answer: Options for Highly Available TopologyThis page explains the two options for configuring the topology of your highly available (HA) Kubernetes clusters.You can set up an HA cluster:With stacked control plane nodes, where etcd nodes are colocated with control plane nodesWith external etcd nodes, where etcd runs on separate nodes from the control planeYou should carefully consider the advantages and disadvantages of each topology before setting up an HA cluster.Note:kubeadm bootstraps the etcd cluster statically. Read the etcd Clustering Guide for more details.Stacked etcd topologyA stacked HA cluster is a topology where the distributed data storage cluster provided by etcd is stacked on top of the cluster formed by the nodes managed by kubeadm that run control plane components.Each control plane node runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. The kube-apiserver is exposed to worker nodes using a load balancer.Each control plane node creates a local etcd member and this etcd member communicates only with the kube-apiserver of this node. The same applies to the local kube-controller-manager and kube-scheduler instances.This topology couples the control planes and etcd members on the same nodes. It is simpler to set up than a cluster with external etcd nodes, and simpler to manage for replication.However, a stacked cluster runs the risk of failed coupling. If one node goes down, both an etcd member and a control plane instance are lost, and redundancy is compromised. You can mitigate this risk by adding more control plane nodes.You should therefore run a minimum of three stacked control plane nodes for an HA cluster.This is the default topology in kubeadm. A local etcd member is created automatically on control plane nodes when using kubeadm init and kubeadm join --control-plane.External etcd topologyAn HA cluster with external etcd is a topology where the distributed data storage cluster provided by etcd is external to the cluster formed by the nodes that run control plane components.Like the stacked etcd topology, each control plane node in an external etcd topology runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. And the kube-apiserver is exposed to worker nodes using a load balancer. However, etcd members run on separate hosts, and each etcd host communicates with the kube-apiserver of each control plane node.This topology decouples the control plane and etcd member. It therefore provides an HA setup where losing a control plane instance or an etcd member has less impact and does not affect the cluster redundancy as much as the stacked HA topology.However, this topology requires twice the number of hosts as the stacked HA topology. A minimum of three hosts for control plane nodes and three hosts for etcd nodes are required for an HA cluster with this topology.What's nextSet up a highly available cluster with kubeadm


Question: What are the benefits of Options for Highly Available Topology?

Answer: Options for Highly Available TopologyThis page explains the two options for configuring the topology of your highly available (HA) Kubernetes clusters.You can set up an HA cluster:With stacked control plane nodes, where etcd nodes are colocated with control plane nodesWith external etcd nodes, where etcd runs on separate nodes from the control planeYou should carefully consider the advantages and disadvantages of each topology before setting up an HA cluster.Note:kubeadm bootstraps the etcd cluster statically. Read the etcd Clustering Guide for more details.Stacked etcd topologyA stacked HA cluster is a topology where the distributed data storage cluster provided by etcd is stacked on top of the cluster formed by the nodes managed by kubeadm that run control plane components.Each control plane node runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. The kube-apiserver is exposed to worker nodes using a load balancer.Each control plane node creates a local etcd member and this etcd member communicates only with the kube-apiserver of this node. The same applies to the local kube-controller-manager and kube-scheduler instances.This topology couples the control planes and etcd members on the same nodes. It is simpler to set up than a cluster with external etcd nodes, and simpler to manage for replication.However, a stacked cluster runs the risk of failed coupling. If one node goes down, both an etcd member and a control plane instance are lost, and redundancy is compromised. You can mitigate this risk by adding more control plane nodes.You should therefore run a minimum of three stacked control plane nodes for an HA cluster.This is the default topology in kubeadm. A local etcd member is created automatically on control plane nodes when using kubeadm init and kubeadm join --control-plane.External etcd topologyAn HA cluster with external etcd is a topology where the distributed data storage cluster provided by etcd is external to the cluster formed by the nodes that run control plane components.Like the stacked etcd topology, each control plane node in an external etcd topology runs an instance of the kube-apiserver, kube-scheduler, and kube-controller-manager. And the kube-apiserver is exposed to worker nodes using a load balancer. However, etcd members run on separate hosts, and each etcd host communicates with the kube-apiserver of each control plane node.This topology decouples the control plane and etcd member. It therefore provides an HA setup where losing a control plane instance or an etcd member has less impact and does not affect the cluster redundancy as much as the stacked HA topology.However, this topology requires twice the number of hosts as the stacked HA topology. A minimum of three hosts for control plane nodes and three hosts for etcd nodes are required for an HA cluster with this topology.What's nextSet up a highly available cluster with kubeadm


Question: What is Options for Highly Available Topology?

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


Question: What is Stacked etcd topology?

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


Question: What is External etcd topology?

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


Question: What is What's next?

Answer: S e t   u p   a   h i g h l y   a v a i l a b l e   c l u s t e r   w i t h   k u b e a d m


Question: What is Windows containers in Kubernetes?

Answer: Windows containers in KubernetesWindows applications constitute a large portion of the services and applications that run in many organizations. Windows containers provide a way to encapsulate processes and package dependencies, making it easier to use DevOps practices and follow cloud native patterns for Windows applications.Organizations with investments in Windows-based applications and Linux-based applications don't have to look for separate orchestrators to manage their workloads, leading to increased operational efficiencies across their deployments, regardless of operating system.Windows nodes in KubernetesTo enable the orchestration of Windows containers in Kubernetes, include Windows nodes in your existing Linux cluster. Scheduling Windows containers in Pods on Kubernetes is similar to scheduling Linux-based containers.In order to run Windows containers, your Kubernetes cluster must include multiple operating systems. While you can only run the control plane on Linux, you can deploy worker nodes running either Windows or Linux.Windows nodes are supported provided that the operating system is Windows Server 2019 or Windows Server 2022.This document uses the term Windows containers to mean Windows containers with process isolation. Kubernetes does not support running Windows containers with Hyper-V isolation.Compatibility and limitationsSome node features are only available if you use a specific container runtime; others are not available on Windows nodes, including:HugePages: not supported for Windows containersPrivileged containers: not supported for Windows containers. HostProcess Containers offer similar functionality.TerminationGracePeriod: requires containerDNot all features of shared namespaces are supported. See API compatibility for more details.See Windows OS version compatibility for details on the Windows versions that Kubernetes is tested against.From an API and kubectl perspective, Windows containers behave in much the same way as Linux-based containers. However, there are some notable differences in key functionality which are outlined in this section.Comparison with LinuxKey Kubernetes elements work the same way in Windows as they do in Linux. This section refers to several key workload abstractions and how they map to Windows.PodsA Pod is the basic building block of Kubernetes–the smallest and simplest unit in the Kubernetes object model that you create or deploy. You may not deploy Windows and Linux containers in the same Pod. All containers in a Pod are scheduled onto a single Node where each Node represents a specific platform and architecture. The following Pod capabilities, properties and events are supported with Windows containers:Single or multiple containers per Pod with process isolation and volume sharingPod status fieldsReadiness, liveness, and startup probespostStart & preStop container lifecycle hooksConfigMap, Secrets: as environment variables or volumesemptyDir volumesNamed pipe host mountsResource limitsOS


Question: How does Windows containers in Kubernetes work?

Answer: Windows containers in KubernetesWindows applications constitute a large portion of the services and applications that run in many organizations. Windows containers provide a way to encapsulate processes and package dependencies, making it easier to use DevOps practices and follow cloud native patterns for Windows applications.Organizations with investments in Windows-based applications and Linux-based applications don't have to look for separate orchestrators to manage their workloads, leading to increased operational efficiencies across their deployments, regardless of operating system.Windows nodes in KubernetesTo enable the orchestration of Windows containers in Kubernetes, include Windows nodes in your existing Linux cluster. Scheduling Windows containers in Pods on Kubernetes is similar to scheduling Linux-based containers.In order to run Windows containers, your Kubernetes cluster must include multiple operating systems. While you can only run the control plane on Linux, you can deploy worker nodes running either Windows or Linux.Windows nodes are supported provided that the operating system is Windows Server 2019 or Windows Server 2022.This document uses the term Windows containers to mean Windows containers with process isolation. Kubernetes does not support running Windows containers with Hyper-V isolation.Compatibility and limitationsSome node features are only available if you use a specific container runtime; others are not available on Windows nodes, including:HugePages: not supported for Windows containersPrivileged containers: not supported for Windows containers. HostProcess Containers offer similar functionality.TerminationGracePeriod: requires containerDNot all features of shared namespaces are supported. See API compatibility for more details.See Windows OS version compatibility for details on the Windows versions that Kubernetes is tested against.From an API and kubectl perspective, Windows containers behave in much the same way as Linux-based containers. However, there are some notable differences in key functionality which are outlined in this section.Comparison with LinuxKey Kubernetes elements work the same way in Windows as they do in Linux. This section refers to several key workload abstractions and how they map to Windows.PodsA Pod is the basic building block of Kubernetes–the smallest and simplest unit in the Kubernetes object model that you create or deploy. You may not deploy Windows and Linux containers in the same Pod. All containers in a Pod are scheduled onto a single Node where each Node represents a specific platform and architecture. The following Pod capabilities, properties and events are supported with Windows containers:Single or multiple containers per Pod with process isolation and volume sharingPod status fieldsReadiness, liveness, and startup probespostStart & preStop container lifecycle hooksConfigMap, Secrets: as environment variables or volumesemptyDir volumesNamed pipe host mountsResource limitsOS


Question: When would you use Windows containers in Kubernetes?

Answer: Windows containers in KubernetesWindows applications constitute a large portion of the services and applications that run in many organizations. Windows containers provide a way to encapsulate processes and package dependencies, making it easier to use DevOps practices and follow cloud native patterns for Windows applications.Organizations with investments in Windows-based applications and Linux-based applications don't have to look for separate orchestrators to manage their workloads, leading to increased operational efficiencies across their deployments, regardless of operating system.Windows nodes in KubernetesTo enable the orchestration of Windows containers in Kubernetes, include Windows nodes in your existing Linux cluster. Scheduling Windows containers in Pods on Kubernetes is similar to scheduling Linux-based containers.In order to run Windows containers, your Kubernetes cluster must include multiple operating systems. While you can only run the control plane on Linux, you can deploy worker nodes running either Windows or Linux.Windows nodes are supported provided that the operating system is Windows Server 2019 or Windows Server 2022.This document uses the term Windows containers to mean Windows containers with process isolation. Kubernetes does not support running Windows containers with Hyper-V isolation.Compatibility and limitationsSome node features are only available if you use a specific container runtime; others are not available on Windows nodes, including:HugePages: not supported for Windows containersPrivileged containers: not supported for Windows containers. HostProcess Containers offer similar functionality.TerminationGracePeriod: requires containerDNot all features of shared namespaces are supported. See API compatibility for more details.See Windows OS version compatibility for details on the Windows versions that Kubernetes is tested against.From an API and kubectl perspective, Windows containers behave in much the same way as Linux-based containers. However, there are some notable differences in key functionality which are outlined in this section.Comparison with LinuxKey Kubernetes elements work the same way in Windows as they do in Linux. This section refers to several key workload abstractions and how they map to Windows.PodsA Pod is the basic building block of Kubernetes–the smallest and simplest unit in the Kubernetes object model that you create or deploy. You may not deploy Windows and Linux containers in the same Pod. All containers in a Pod are scheduled onto a single Node where each Node represents a specific platform and architecture. The following Pod capabilities, properties and events are supported with Windows containers:Single or multiple containers per Pod with process isolation and volume sharingPod status fieldsReadiness, liveness, and startup probespostStart & preStop container lifecycle hooksConfigMap, Secrets: as environment variables or volumesemptyDir volumesNamed pipe host mountsResource limitsOS


Question: What are the benefits of Windows containers in Kubernetes?

Answer: Windows containers in KubernetesWindows applications constitute a large portion of the services and applications that run in many organizations. Windows containers provide a way to encapsulate processes and package dependencies, making it easier to use DevOps practices and follow cloud native patterns for Windows applications.Organizations with investments in Windows-based applications and Linux-based applications don't have to look for separate orchestrators to manage their workloads, leading to increased operational efficiencies across their deployments, regardless of operating system.Windows nodes in KubernetesTo enable the orchestration of Windows containers in Kubernetes, include Windows nodes in your existing Linux cluster. Scheduling Windows containers in Pods on Kubernetes is similar to scheduling Linux-based containers.In order to run Windows containers, your Kubernetes cluster must include multiple operating systems. While you can only run the control plane on Linux, you can deploy worker nodes running either Windows or Linux.Windows nodes are supported provided that the operating system is Windows Server 2019 or Windows Server 2022.This document uses the term Windows containers to mean Windows containers with process isolation. Kubernetes does not support running Windows containers with Hyper-V isolation.Compatibility and limitationsSome node features are only available if you use a specific container runtime; others are not available on Windows nodes, including:HugePages: not supported for Windows containersPrivileged containers: not supported for Windows containers. HostProcess Containers offer similar functionality.TerminationGracePeriod: requires containerDNot all features of shared namespaces are supported. See API compatibility for more details.See Windows OS version compatibility for details on the Windows versions that Kubernetes is tested against.From an API and kubectl perspective, Windows containers behave in much the same way as Linux-based containers. However, there are some notable differences in key functionality which are outlined in this section.Comparison with LinuxKey Kubernetes elements work the same way in Windows as they do in Linux. This section refers to several key workload abstractions and how they map to Windows.PodsA Pod is the basic building block of Kubernetes–the smallest and simplest unit in the Kubernetes object model that you create or deploy. You may not deploy Windows and Linux containers in the same Pod. All containers in a Pod are scheduled onto a single Node where each Node represents a specific platform and architecture. The following Pod capabilities, properties and events are supported with Windows containers:Single or multiple containers per Pod with process isolation and volume sharingPod status fieldsReadiness, liveness, and startup probespostStart & preStop container lifecycle hooksConfigMap, Secrets: as environment variables or volumesemptyDir volumesNamed pipe host mountsResource limitsOS


Question: What is Windows containers in Kubernetes?

Answer: W i n d o w s   a p p l i c a t i o n s   c o n s t i t u t e   a   l a r g e   p o r t i o n   o f   t h e   s e r v i c e s   a n d   a p p l i c a t i o n s   t h a t   r u n   i n   m a n y   o r g a n i z a t i o n s .   W i n d o w s   c o n t a i n e r s   p r o v i d e   a   w a y   t o   e n c a p s u l a t e   p r o c e s s e s   a n d   p a c k a g e   d e p e n d e n c i e s ,   m a k i n g   i t   e a s i e r   t o   u s e   D e v O p s   p r a c t i c e s   a n d   f o l l o w   c l o u d   n a t i v e   p a t t e r n s   f o r   W i n d o w s   a p p l i c a t i o n s .   O r g a n i z a t i o n s   w i t h   i n v e s t m e n t s   i n   W i n d o w s - b a s e d   a p p l i c a t i o n s   a n d   L i n u x - b a s e d   a p p l i c a t i o n s   d o n ' t   h a v e   t o   l o o k   f o r   s e p a r a t e   o r c h e s t r a t o r s   t o   m a n a g e   t h e i r   w o r k l o a d s ,   l e a d i n g   t o   i n c r e a s e d   o p e r a t i o n a l   e f f i c i e n c i e s   a c r o s s   t h e i r   d e p l o y m e n t s ,   r e g a r d l e s s   o f   o p e r a t i n g   s y s t e m .


Question: What is Windows nodes in Kubernetes?

Answer: T o   e n a b l e   t h e   o r c h e s t r a t i o n   o f   W i n d o w s   c o n t a i n e r s   i n   K u b e r n e t e s ,   i n c l u d e   W i n d o w s   n o d e s   i n   y o u r   e x i s t i n g   L i n u x   c l u s t e r .   S c h e d u l i n g   W i n d o w s   c o n t a i n e r s   i n   P o d s   o n   K u b e r n e t e s   i s   s i m i l a r   t o   s c h e d u l i n g   L i n u x - b a s e d   c o n t a i n e r s .   I n   o r d e r   t o   r u n   W i n d o w s   c o n t a i n e r s ,   y o u r   K u b e r n e t e s   c l u s t e r   m u s t   i n c l u d e   m u l t i p l e   o p e r a t i n g   s y s t e m s .   W h i l e   y o u   c a n   o n l y   r u n   t h e   c o n t r o l   p l a n e   o n   L i n u x ,   y o u   c a n   d e p l o y   w o r k e r   n o d e s   r u n n i n g   e i t h e r   W i n d o w s   o r   L i n u x .   W i n d o w s   n o d e s   a r e   s u p p o r t e d   p r o v i d e d   t h a t   t h e   o p e r a t i n g   s y s t e m   i s   W i n d o w s   S e r v e r   2 0 1 9   o r   W i n d o w s   S e r v e r   2 0 2 2 .   T h i s   d o c u m e n t   u s e s   t h e   t e r m   W i n d o w s   c o n t a i n e r s   t o   m e a n   W i n d o w s   c o n t a i n e r s   w i t h   p r o c e s s   i s o l a t i o n .   K u b e r n e t e s   d o e s   n o t   s u p p o r t   r u n n i n g   W i n d o w s   c o n t a i n e r s   w i t h   H y p e r - V   i s o l a t i o n .


Question: What is Compatibility and limitations?

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


Question: What is Comparison with Linux?

Answer: K e y   K u b e r n e t e s   e l e m e n t s   w o r k   t h e   s a m e   w a y   i n   W i n d o w s   a s   t h e y   d o   i n   L i n u x .   T h i s   s e c t i o n   r e f e r s   t o   s e v e r a l   k e y   w o r k l o a d   a b s t r a c t i o n s   a n d   h o w   t h e y   m a p   t o   W i n d o w s .   P o d s A   P o d   i s   t h e   b a s i c   b u i l d i n g   b l o c k   o f   K u b e r n e t e s – t h e   s m a l l e s t   a n d   s i m p l e s t   u n i t   i n   t h e   K u b e r n e t e s   o b j e c t   m o d e l   t h a t   y o u   c r e a t e   o r   d e p l o y .   Y o u   m a y   n o t   d e p l o y   W i n d o w s   a n d   L i n u x   c o n t a i n e r s   i n   t h e   s a m e   P o d .   A l l   c o n t a i n e r s   i n   a   P o d   a r e   s c h e d u l e d   o n t o   a   s i n g l e   N o d e   w h e r e   e a c h   N o d e   r e p r e s e n t s   a   s p e c i f i c   p l a t f o r m   a n d   a r c h i t e c t u r e .   T h e   f o l l o w i n g   P o d   c a p a b i l i t i e s ,   p r o p e r t i e s   a n d   e v e n t s   a r e   s u p p o r t e d   w i t h   W i n d o w s   c o n t a i n e r s : S i n g l e   o r   m u l t i p l e   c o n t a i n e r s   p e r   P o d   w i t h   p r o c e s s   i s o l a t i o n   a n d   v o l u m e   s h a r i n g P o d   s t a t u s   f i e l d s R e a d i n e s s ,   l i v e n e s s ,   a n d   s t a r t u p   p r o b e s p o s t S t a r t   &   p r e S t o p   c o n t a i n e r   l i f e c y c l e   h o o k s C o n f i g M a p ,   S e c r e t s :   a s   e n v i r o n m e n t   v a r i a b l e s   o r   v o l u m e s e m p t y D i r   v o l u m e s N a m e d   p i p e   h o s t   m o u n t s R e s o u r c e   l i m i t s O S   f i e l d : T h e   . s p e c . o s . n a m e   f i e l d   s h o u l d   b e   s e t   t o   w i n d o w s   t o   i n d i c a t e   t h a t   t h e   c u r r e n t   P o d   u s e s   W i n d o w s   c o n t a i n e r s . I f   y o u   s e t   t h e   . s


Question: What is Command line options for the kubelet?

Answer: S o m e   k u b e l e t   c o m m a n d   l i n e   o p t i o n s   b e h a v e   d i f f e r e n t l y   o n   W i n d o w s ,   a s   d e s c r i b e d   b e l o w :   T h e   - - w i n d o w s - p r i o r i t y c l a s s   l e t s   y o u   s e t   t h e   s c h e d u l i n g   p r i o r i t y   o f   t h e   k u b e l e t   p r o c e s s   ( s e e   C P U   r e s o u r c e   m a n a g e m e n t ) T h e   - - k u b e - r e s e r v e d ,   - - s y s t e m - r e s e r v e d   ,   a n d   - - e v i c t i o n - h a r d   f l a g s   u p d a t e   N o d e A l l o c a t a b l e E v i c t i o n   b y   u s i n g   - - e n f o r c e - n o d e - a l l o c a b l e   i s   n o t   i m p l e m e n t e d W h e n   r u n n i n g   o n   a   W i n d o w s   n o d e   t h e   k u b e l e t   d o e s   n o t   h a v e   m e m o r y   o r   C P U   r e s t r i c t i o n s .   - - k u b e - r e s e r v e d   a n d   - - s y s t e m - r e s e r v e d   o n l y   s u b t r a c t   f r o m   N o d e A l l o c a t a b l e   a n d   d o   n o t   g u a r a n t e e   r e s o u r c e   p r o v i d e d   f o r   w o r k l o a d s .   S e e   R e s o u r c e   M a n a g e m e n t   f o r   W i n d o w s   n o d e s   f o r   m o r e   i n f o r m a t i o n . T h e   P I D P r e s s u r e   C o n d i t i o n   i s   n o t   i m p l e m e n t e d T h e   k u b e l e t   d o e s   n o t   t a k e   O O M   e v i c t i o n   a c t i o n s


Question: What is API compatibility?

Answer: T h e r e   a r e   s u b t l e   d i f f e r e n c e s   i n   t h e   w a y   t h e   K u b e r n e t e s   A P I s   w o r k   f o r   W i n d o w s   d u e   t o   t h e   O S   a n d   c o n t a i n e r   r u n t i m e .   S o m e   w o r k l o a d   p r o p e r t i e s   w e r e   d e s i g n e d   f o r   L i n u x ,   a n d   f a i l   t o   r u n   o n   W i n d o w s .   A t   a   h i g h   l e v e l ,   t h e s e   O S   c o n c e p t s   a r e   d i f f e r e n t :   I d e n t i t y   -   L i n u x   u s e s   u s e r I D   ( U I D )   a n d   g r o u p I D   ( G I D )   w h i c h   a r e   r e p r e s e n t e d   a s   i n t e g e r   t y p e s .   U s e r   a n d   g r o u p   n a m e s   a r e   n o t   c a n o n i c a l   -   t h e y   a r e   j u s t   a n   a l i a s   i n   / e t c / g r o u p s   o r   / e t c / p a s s w d   b a c k   t o   U I D + G I D .   W i n d o w s   u s e s   a   l a r g e r   b i n a r y   s e c u r i t y   i d e n t i f i e r   ( S I D )   w h i c h   i s   s t o r e d   i n   t h e   W i n d o w s   S e c u r i t y   A c c e s s   M a n a g e r   ( S A M )   d a t a b a s e .   T h i s   d a t a b a s e   i s   n o t   s h a r e d   b e t w e e n   t h e   h o s t   a n d   c o n t a i n e r s ,   o r   b e t w e e n   c o n t a i n e r s . F i l e   p e r m i s s i o n s   -   W i n d o w s   u s e s   a n   a c c e s s   c o n t r o l   l i s t   b a s e d   o n   ( S I D s ) ,   w h e r e a s   P O S I X   s y s t e m s   s u c h   a s   L i n u x   u s e   a   b i t m a s k   b a s e d   o n   o b j e c t   p e r m i s s i o n s   a n d   U I D + G I D ,   p l u s   o p t i o n a l   a c c e s s   c o n t r o l   l i s t s . F i l e   p a t h s   -   t h e   c o n v e n t i o n   o n   W i n d o w s   i s   t o   u s e   \   i n s t e a d   o f   / .   T h e   G o   I O   l i b r a r i e s   t y p i c a l l y   a c c e p t   b o t h   a n d   j u s t   m a k e   i t   w o r k ,   b u t   w h e n   y o u ' r e   s


Question: What is Field compatibility for container specifications?

Answer: T h e   f o l l o w i n g   l i s t   d o c u m e n t s   d i f f e r e n c e s   b e t w e e n   h o w   P o d   c o n t a i n e r   s p e c i f i c a t i o n s   w o r k   b e t w e e n   W i n d o w s   a n d   L i n u x :   H u g e   p a g e s   a r e   n o t   i m p l e m e n t e d   i n   t h e   W i n d o w s   c o n t a i n e r   r u n t i m e ,   a n d   a r e   n o t   a v a i l a b l e .   T h e y   r e q u i r e   a s s e r t i n g   a   u s e r   p r i v i l e g e   t h a t ' s   n o t   c o n f i g u r a b l e   f o r   c o n t a i n e r s . r e q u e s t s . c p u   a n d   r e q u e s t s . m e m o r y   -   r e q u e s t s   a r e   s u b t r a c t e d   f r o m   n o d e   a v a i l a b l e   r e s o u r c e s ,   s o   t h e y   c a n   b e   u s e d   t o   a v o i d   o v e r p r o v i s i o n i n g   a   n o d e .   H o w e v e r ,   t h e y   c a n n o t   b e   u s e d   t o   g u a r a n t e e   r e s o u r c e s   i n   a n   o v e r p r o v i s i o n e d   n o d e .   T h e y   s h o u l d   b e   a p p l i e d   t o   a l l   c o n t a i n e r s   a s   a   b e s t   p r a c t i c e   i f   t h e   o p e r a t o r   w a n t s   t o   a v o i d   o v e r p r o v i s i o n i n g   e n t i r e l y . s e c u r i t y C o n t e x t . a l l o w P r i v i l e g e E s c a l a t i o n   -   n o t   p o s s i b l e   o n   W i n d o w s ;   n o n e   o f   t h e   c a p a b i l i t i e s   a r e   h o o k e d   u p s e c u r i t y C o n t e x t . c a p a b i l i t i e s   -   P O S I X   c a p a b i l i t i e s   a r e   n o t   i m p l e m e n t e d   o n   W i n d o w s s e c u r i t y C o n t e x t . p r i v i l e g e d   -   W i n d o w s   d o e s n ' t   s u p p o r t   p r i v i l e g e d   c o n t a i n e r s ,   u s e   H o s t P r o c e s s   C o n t a i n e r s   i n s t e a d s e c u r i t y C o n t e x t . p r o c M o u n t   -   W i n d o w s   d o e s n ' t   h a v e   a   / p r o c   f i l e s y s t e m s e c u r i t y C o n t e x t


Question: What is Field compatibility for Pod specifications?

Answer: T h e   f o l l o w i n g   l i s t   d o c u m e n t s   d i f f e r e n c e s   b e t w e e n   h o w   P o d   s p e c i f i c a t i o n s   w o r k   b e t w e e n   W i n d o w s   a n d   L i n u x :   h o s t I P C   a n d   h o s t p i d   -   h o s t   n a m e s p a c e   s h a r i n g   i s   n o t   p o s s i b l e   o n   W i n d o w s h o s t N e t w o r k   -   h o s t   n e t w o r k i n g   i s   n o t   p o s s i b l e   o n   W i n d o w s d n s P o l i c y   -   s e t t i n g   t h e   P o d   d n s P o l i c y   t o   C l u s t e r F i r s t W i t h H o s t N e t   i s   n o t   s u p p o r t e d   o n   W i n d o w s   b e c a u s e   h o s t   n e t w o r k i n g   i s   n o t   p r o v i d e d .   P o d s   a l w a y s   r u n   w i t h   a   c o n t a i n e r   n e t w o r k . p o d S e c u r i t y C o n t e x t   s e e   b e l o w s h a r e P r o c e s s N a m e s p a c e   -   t h i s   i s   a   b e t a   f e a t u r e ,   a n d   d e p e n d s   o n   L i n u x   n a m e s p a c e s   w h i c h   a r e   n o t   i m p l e m e n t e d   o n   W i n d o w s .   W i n d o w s   c a n n o t   s h a r e   p r o c e s s   n a m e s p a c e s   o r   t h e   c o n t a i n e r ' s   r o o t   f i l e s y s t e m .   O n l y   t h e   n e t w o r k   c a n   b e   s h a r e d . t e r m i n a t i o n G r a c e P e r i o d S e c o n d s   -   t h i s   i s   n o t   f u l l y   i m p l e m e n t e d   i n   D o c k e r   o n   W i n d o w s ,   s e e   t h e   G i t H u b   i s s u e .   T h e   b e h a v i o r   t o d a y   i s   t h a t   t h e   E N T R Y P O I N T   p r o c e s s   i s   s e n t   C T R L _ S H U T D O W N _ E V E N T ,   t h e n   W i n d o w s   w a i t s   5   s e c o n d s   b y   d e f a u l t ,   a n d   f i n a l l y   s h u t s   d o w n   a l l   p r o c e s s e s   u s i n g   t h e   n o r m a l   W i n d o w s   s h u t d o w n   b e h a v i o r .   T h e   5   s e c o n d   d e f a u l t   i s   a c t u a l l y   i


Question: What is Host network access?

Answer: K u b e r n e t e s   v 1 . 2 6   t o   v 1 . 3 2   i n c l u d e d   a l p h a   s u p p o r t   f o r   r u n n i n g   W i n d o w s   P o d s   i n   t h e   h o s t ' s   n e t w o r k   n a m e s p a c e .   K u b e r n e t e s   v 1 . 3 4   d o e s   n o t   i n c l u d e   t h e   W i n d o w s H o s t N e t w o r k   f e a t u r e   g a t e   o r   s u p p o r t   f o r   r u n n i n g   W i n d o w s   P o d s   i n   t h e   h o s t ' s   n e t w o r k   n a m e s p a c e .


Question: What is Field compatibility for Pod security context?

Answer: O n l y   t h e   s e c u r i t y C o n t e x t . r u n A s N o n R o o t   a n d   s e c u r i t y C o n t e x t . w i n d o w s O p t i o n s   f r o m   t h e   P o d   s e c u r i t y C o n t e x t   f i e l d s   w o r k   o n   W i n d o w s .


Question: What is Node problem detector?

Answer: T h e   n o d e   p r o b l e m   d e t e c t o r   ( s e e   M o n i t o r   N o d e   H e a l t h )   h a s   p r e l i m i n a r y   s u p p o r t   f o r   W i n d o w s .   F o r   m o r e   i n f o r m a t i o n ,   v i s i t   t h e   p r o j e c t ' s   G i t H u b   p a g e .


Question: What is Pause container?

Answer: I n   a   K u b e r n e t e s   P o d ,   a n   i n f r a s t r u c t u r e   o r   “ p a u s e ”   c o n t a i n e r   i s   f i r s t   c r e a t e d   t o   h o s t   t h e   c o n t a i n e r .   I n   L i n u x ,   t h e   c g r o u p s   a n d   n a m e s p a c e s   t h a t   m a k e   u p   a   p o d   n e e d   a   p r o c e s s   t o   m a i n t a i n   t h e i r   c o n t i n u e d   e x i s t e n c e ;   t h e   p a u s e   p r o c e s s   p r o v i d e s   t h i s .   C o n t a i n e r s   t h a t   b e l o n g   t o   t h e   s a m e   p o d ,   i n c l u d i n g   i n f r a s t r u c t u r e   a n d   w o r k e r   c o n t a i n e r s ,   s h a r e   a   c o m m o n   n e t w o r k   e n d p o i n t   ( s a m e   I P v 4   a n d   /   o r   I P v 6   a d d r e s s ,   s a m e   n e t w o r k   p o r t   s p a c e s ) .   K u b e r n e t e s   u s e s   p a u s e   c o n t a i n e r s   t o   a l l o w   f o r   w o r k e r   c o n t a i n e r s   c r a s h i n g   o r   r e s t a r t i n g   w i t h o u t   l o s i n g   a n y   o f   t h e   n e t w o r k i n g   c o n f i g u r a t i o n .   K u b e r n e t e s   m a i n t a i n s   a   m u l t i - a r c h i t e c t u r e   i m a g e   t h a t   i n c l u d e s   s u p p o r t   f o r   W i n d o w s .   F o r   K u b e r n e t e s   v 1 . 3 4 . 0   t h e   r e c o m m e n d e d   p a u s e   i m a g e   i s   r e g i s t r y . k 8 s . i o / p a u s e : 3 . 6 .   T h e   s o u r c e   c o d e   i s   a v a i l a b l e   o n   G i t H u b .   M i c r o s o f t   m a i n t a i n s   a   d i f f e r e n t   m u l t i - a r c h i t e c t u r e   i m a g e ,   w i t h   L i n u x   a n d   W i n d o w s   a m d 6 4   s u p p o r t ,   t h a t   y o u   c a n   f i n d   a s   m c r . m i c r o s o f t . c o m / o s s / k u b e r n e t e s / p a u s e : 3 . 6 .   T h i s   i m a g e   i s   b u i l t   f r o m   t h e   s a m e   s o u r c e   a s   t h e   K u b e r n e t e s   m a i n t a i n e d   i m


Question: What is Container runtimes?

Answer: Y o u   n e e d   t o   i n s t a l l   a   c o n t a i n e r   r u n t i m e   i n t o   e a c h   n o d e   i n   t h e   c l u s t e r   s o   t h a t   P o d s   c a n   r u n   t h e r e .   T h e   f o l l o w i n g   c o n t a i n e r   r u n t i m e s   w o r k   w i t h   W i n d o w s :


Question: What is ContainerD?

Answer: Y o u   c a n   u s e   C o n t a i n e r D   1 . 4 . 0 +   a s   t h e   c o n t a i n e r   r u n t i m e   f o r   K u b e r n e t e s   n o d e s   t h a t   r u n   W i n d o w s .   L e a r n   h o w   t o   i n s t a l l   C o n t a i n e r D   o n   a   W i n d o w s   n o d e . N o t e : T h e r e   i s   a   k n o w n   l i m i t a t i o n   w h e n   u s i n g   G M S A   w i t h   c o n t a i n e r d   t o   a c c e s s   W i n d o w s   n e t w o r k   s h a r e s ,   w h i c h   r e q u i r e s   a   k e r n e l   p a t c h .


Question: What is Mirantis Container Runtime?

Answer: M i r a n t i s   C o n t a i n e r   R u n t i m e   ( M C R )   i s   a v a i l a b l e   a s   a   c o n t a i n e r   r u n t i m e   f o r   a l l   W i n d o w s   S e r v e r   2 0 1 9   a n d   l a t e r   v e r s i o n s .   S e e   I n s t a l l   M C R   o n   W i n d o w s   S e r v e r s   f o r   m o r e   i n f o r m a t i o n .


Question: What is Windows OS version compatibility?

Answer: O n   W i n d o w s   n o d e s ,   s t r i c t   c o m p a t i b i l i t y   r u l e s   a p p l y   w h e r e   t h e   h o s t   O S   v e r s i o n   m u s t   m a t c h   t h e   c o n t a i n e r   b a s e   i m a g e   O S   v e r s i o n .   O n l y   W i n d o w s   c o n t a i n e r s   w i t h   a   c o n t a i n e r   o p e r a t i n g   s y s t e m   o f   W i n d o w s   S e r v e r   2 0 1 9   a r e   f u l l y   s u p p o r t e d .   F o r   K u b e r n e t e s   v 1 . 3 4 ,   o p e r a t i n g   s y s t e m   c o m p a t i b i l i t y   f o r   W i n d o w s   n o d e s   ( a n d   P o d s )   i s   a s   f o l l o w s :   T h e   K u b e r n e t e s   v e r s i o n - s k e w   p o l i c y   a l s o   a p p l i e s .


Question: What is Note:?

Answer: 6 4 - b i t   p r o c e s s o r   4   C P U   c o r e s   o r   m o r e ,   c a p a b l e   o f   s u p p o r t i n g   v i r t u a l i z a t i o n 8 G B   o r   m o r e   o f   R A M 5 0 G B   o r   m o r e   o f   f r e e   d i s k   s p a c e   R e f e r   t o   H a r d w a r e   r e q u i r e m e n t s   f o r   W i n d o w s   S e r v e r   M i c r o s o f t   d o c u m e n t a t i o n   f o r   t h e   m o s t   u p - t o - d a t e   i n f o r m a t i o n   o n   m i n i m u m   h a r d w a r e   r e q u i r e m e n t s .   F o r   g u i d a n c e   o n   d e c i d i n g   o n   r e s o u r c e s   f o r   p r o d u c t i o n   w o r k e r   n o d e s   r e f e r   t o   P r o d u c t i o n   w o r k e r   n o d e s   K u b e r n e t e s   d o c u m e n t a t i o n .   T o   o p t i m i z e   s y s t e m   r e s o u r c e s ,   i f   a   g r a p h i c a l   u s e r   i n t e r f a c e   i s   n o t   r e q u i r e d ,   i t   m a y   b e   p r e f e r a b l e   t o   u s e   a   W i n d o w s   S e r v e r   O S   i n s t a l l a t i o n   t h a t   e x c l u d e s   t h e   W i n d o w s   D e s k t o p   E x p e r i e n c e   i n s t a l l a t i o n   o p t i o n ,   a s   t h i s   c o n f i g u r a t i o n   t y p i c a l l y   f r e e s   u p   m o r e   s y s t e m   r e s o u r c e s .   I n   a s s e s s i n g   d i s k   s p a c e   f o r   W i n d o w s   w o r k e r   n o d e s ,   t a k e   n o t e   t h a t   W i n d o w s   c o n t a i n e r   i m a g e s   a r e   t y p i c a l l y   l a r g e r   t h a n   L i n u x   c o n t a i n e r   i m a g e s ,   w i t h   c o n t a i n e r   i m a g e   s i z e s   r a n g i n g   f r o m   3 0 0 M B   t o   o v e r   1 0 G B   f o r   a   s i n g l e   i m a g e .   A d d i t i o n a l l y ,   t a k e   n o t e   t h a t   t h e   C :   d r i v e   i n   W i n d o w s   c o n t a i n e r s   r e p r e s e n t s   a   v i r t u a l   f r e e   s i z e   o f   2 0 G B   b y   d e f a u l t ,   w h i c h


Question: What is Getting help and troubleshooting?

Answer: Y o u r   m a i n   s o u r c e   o f   h e l p   f o r   t r o u b l e s h o o t i n g   y o u r   K u b e r n e t e s   c l u s t e r   s h o u l d   s t a r t   w i t h   t h e   T r o u b l e s h o o t i n g   p a g e .   S o m e   a d d i t i o n a l ,   W i n d o w s - s p e c i f i c   t r o u b l e s h o o t i n g   h e l p   i s   i n c l u d e d   i n   t h i s   s e c t i o n .   L o g s   a r e   a n   i m p o r t a n t   e l e m e n t   o f   t r o u b l e s h o o t i n g   i s s u e s   i n   K u b e r n e t e s .   M a k e   s u r e   t o   i n c l u d e   t h e m   a n y   t i m e   y o u   s e e k   t r o u b l e s h o o t i n g   a s s i s t a n c e   f r o m   o t h e r   c o n t r i b u t o r s .   F o l l o w   t h e   i n s t r u c t i o n s   i n   t h e   S I G   W i n d o w s   c o n t r i b u t i n g   g u i d e   o n   g a t h e r i n g   l o g s .


Question: What is Reporting issues and feature requests?

Answer: I f   y o u   h a v e   w h a t   l o o k s   l i k e   a   b u g ,   o r   y o u   w o u l d   l i k e   t o   m a k e   a   f e a t u r e   r e q u e s t ,   p l e a s e   f o l l o w   t h e   S I G   W i n d o w s   c o n t r i b u t i n g   g u i d e   t o   c r e a t e   a   n e w   i s s u e .   Y o u   s h o u l d   f i r s t   s e a r c h   t h e   l i s t   o f   i s s u e s   i n   c a s e   i t   w a s   r e p o r t e d   p r e v i o u s l y   a n d   c o m m e n t   w i t h   y o u r   e x p e r i e n c e   o n   t h e   i s s u e   a n d   a d d   a d d i t i o n a l   l o g s .   S I G   W i n d o w s   c h a n n e l   o n   t h e   K u b e r n e t e s   S l a c k   i s   a l s o   a   g r e a t   a v e n u e   t o   g e t   s o m e   i n i t i a l   s u p p o r t   a n d   t r o u b l e s h o o t i n g   i d e a s   p r i o r   t o   c r e a t i n g   a   t i c k e t .


Question: What is Validating the Windows cluster operability?

Answer: T h e   K u b e r n e t e s   p r o j e c t   p r o v i d e s   a   W i n d o w s   O p e r a t i o n a l   R e a d i n e s s   s p e c i f i c a t i o n ,   a c c o m p a n i e d   b y   a   s t r u c t u r e d   t e s t   s u i t e .   T h i s   s u i t e   i s   s p l i t   i n t o   t w o   s e t s   o f   t e s t s ,   c o r e   a n d   e x t e n d e d ,   e a c h   c o n t a i n i n g   c a t e g o r i e s   a i m e d   a t   t e s t i n g   s p e c i f i c   a r e a s .   I t   c a n   b e   u s e d   t o   v a l i d a t e   a l l   t h e   f u n c t i o n a l i t i e s   o f   a   W i n d o w s   a n d   h y b r i d   s y s t e m   ( m i x e d   w i t h   L i n u x   n o d e s )   w i t h   f u l l   c o v e r a g e .   T o   s e t   u p   t h e   p r o j e c t   o n   a   n e w l y   c r e a t e d   c l u s t e r ,   r e f e r   t o   t h e   i n s t r u c t i o n s   i n   t h e   p r o j e c t   g u i d e .


Question: What is Deployment tools?

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


Question: What is Windows distribution channels?

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


Question: What is Attach Handlers to Container Lifecycle Events?

Answer: Attach Handlers to Container Lifecycle EventsThis page shows how to attach handlers to Container lifecycle events. Kubernetes supports the postStart and preStop events. Kubernetes sends the postStart event immediately after a Container is started, and it sends the preStop event immediately before the Container is terminated. A Container may specify one handler per event.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.Define postStart and preStop handlersIn this exercise, you create a Pod that has one Container. The Container has handlers for the postStart and preStop events.Here is the configuration file for the Pod:pods/lifecycle-events.yaml apiVersion: v1 kind: Pod metadata: name: lifecycle-demo spec: containers: - name: lifecycle-demo-container image: nginx lifecycle: postStart: exec: command: ["/bin/sh", "-c", "echo Hello from the postStart handler > /usr/share/message"] preStop: exec: command: ["/bin/sh","-c","nginx -s quit; while killall -0 nginx; do sleep 1; done"] In the configuration file, you can see that the postStart command writes a message file to the Container's /usr/share directory. The preStop command shuts down nginx gracefully. This is helpful if the Container is being terminated because of a failure.Create the Pod:kubectl apply -f https://k8s.io/examples/pods/lifecycle-events.yaml Verify that the Container in the Pod is running:kubectl get pod lifecycle-demo Get a shell into the Container running in your Pod:kubectl exec -it lifecycle-demo -- /bin/bash In your shell, verify that the postStart handler created the message file:root@lifecycle-demo:/# cat /usr/share/message The output shows the text written by the postStart handler:Hello from the postStart handler DiscussionKubernetes sends the postStart event immediately after the Container is created. There is no guarantee, however, that the postStart handler is called before the Container's entrypoint is called. The postStart handler runs asynchronously relative to the Container's code, but Kubernetes' management of the container blocks until the postStart handler completes. The Container's status is not set to RUNNING until the postStart handler completes.Kubernetes sends the preStop event immediately before the Container is terminated. Kubernetes' management of the Container blocks until the preStop handler completes, unless the Pod's grace period expires. For more details, see Pod Lifecycle.Note:Kubernetes only sends the preStop event when a Pod or a container in the Pod is terminated. This means that the preStop hook is not invoked when the Pod is


Question: How does Attach Handlers to Container Lifecycle Events work?

Answer: Attach Handlers to Container Lifecycle EventsThis page shows how to attach handlers to Container lifecycle events. Kubernetes supports the postStart and preStop events. Kubernetes sends the postStart event immediately after a Container is started, and it sends the preStop event immediately before the Container is terminated. A Container may specify one handler per event.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.Define postStart and preStop handlersIn this exercise, you create a Pod that has one Container. The Container has handlers for the postStart and preStop events.Here is the configuration file for the Pod:pods/lifecycle-events.yaml apiVersion: v1 kind: Pod metadata: name: lifecycle-demo spec: containers: - name: lifecycle-demo-container image: nginx lifecycle: postStart: exec: command: ["/bin/sh", "-c", "echo Hello from the postStart handler > /usr/share/message"] preStop: exec: command: ["/bin/sh","-c","nginx -s quit; while killall -0 nginx; do sleep 1; done"] In the configuration file, you can see that the postStart command writes a message file to the Container's /usr/share directory. The preStop command shuts down nginx gracefully. This is helpful if the Container is being terminated because of a failure.Create the Pod:kubectl apply -f https://k8s.io/examples/pods/lifecycle-events.yaml Verify that the Container in the Pod is running:kubectl get pod lifecycle-demo Get a shell into the Container running in your Pod:kubectl exec -it lifecycle-demo -- /bin/bash In your shell, verify that the postStart handler created the message file:root@lifecycle-demo:/# cat /usr/share/message The output shows the text written by the postStart handler:Hello from the postStart handler DiscussionKubernetes sends the postStart event immediately after the Container is created. There is no guarantee, however, that the postStart handler is called before the Container's entrypoint is called. The postStart handler runs asynchronously relative to the Container's code, but Kubernetes' management of the container blocks until the postStart handler completes. The Container's status is not set to RUNNING until the postStart handler completes.Kubernetes sends the preStop event immediately before the Container is terminated. Kubernetes' management of the Container blocks until the preStop handler completes, unless the Pod's grace period expires. For more details, see Pod Lifecycle.Note:Kubernetes only sends the preStop event when a Pod or a container in the Pod is terminated. This means that the preStop hook is not invoked when the Pod is


Question: When would you use Attach Handlers to Container Lifecycle Events?

Answer: Attach Handlers to Container Lifecycle EventsThis page shows how to attach handlers to Container lifecycle events. Kubernetes supports the postStart and preStop events. Kubernetes sends the postStart event immediately after a Container is started, and it sends the preStop event immediately before the Container is terminated. A Container may specify one handler per event.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.Define postStart and preStop handlersIn this exercise, you create a Pod that has one Container. The Container has handlers for the postStart and preStop events.Here is the configuration file for the Pod:pods/lifecycle-events.yaml apiVersion: v1 kind: Pod metadata: name: lifecycle-demo spec: containers: - name: lifecycle-demo-container image: nginx lifecycle: postStart: exec: command: ["/bin/sh", "-c", "echo Hello from the postStart handler > /usr/share/message"] preStop: exec: command: ["/bin/sh","-c","nginx -s quit; while killall -0 nginx; do sleep 1; done"] In the configuration file, you can see that the postStart command writes a message file to the Container's /usr/share directory. The preStop command shuts down nginx gracefully. This is helpful if the Container is being terminated because of a failure.Create the Pod:kubectl apply -f https://k8s.io/examples/pods/lifecycle-events.yaml Verify that the Container in the Pod is running:kubectl get pod lifecycle-demo Get a shell into the Container running in your Pod:kubectl exec -it lifecycle-demo -- /bin/bash In your shell, verify that the postStart handler created the message file:root@lifecycle-demo:/# cat /usr/share/message The output shows the text written by the postStart handler:Hello from the postStart handler DiscussionKubernetes sends the postStart event immediately after the Container is created. There is no guarantee, however, that the postStart handler is called before the Container's entrypoint is called. The postStart handler runs asynchronously relative to the Container's code, but Kubernetes' management of the container blocks until the postStart handler completes. The Container's status is not set to RUNNING until the postStart handler completes.Kubernetes sends the preStop event immediately before the Container is terminated. Kubernetes' management of the Container blocks until the preStop handler completes, unless the Pod's grace period expires. For more details, see Pod Lifecycle.Note:Kubernetes only sends the preStop event when a Pod or a container in the Pod is terminated. This means that the preStop hook is not invoked when the Pod is


Question: What are the benefits of Attach Handlers to Container Lifecycle Events?

Answer: Attach Handlers to Container Lifecycle EventsThis page shows how to attach handlers to Container lifecycle events. Kubernetes supports the postStart and preStop events. Kubernetes sends the postStart event immediately after a Container is started, and it sends the preStop event immediately before the Container is terminated. A Container may specify one handler per event.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.Define postStart and preStop handlersIn this exercise, you create a Pod that has one Container. The Container has handlers for the postStart and preStop events.Here is the configuration file for the Pod:pods/lifecycle-events.yaml apiVersion: v1 kind: Pod metadata: name: lifecycle-demo spec: containers: - name: lifecycle-demo-container image: nginx lifecycle: postStart: exec: command: ["/bin/sh", "-c", "echo Hello from the postStart handler > /usr/share/message"] preStop: exec: command: ["/bin/sh","-c","nginx -s quit; while killall -0 nginx; do sleep 1; done"] In the configuration file, you can see that the postStart command writes a message file to the Container's /usr/share directory. The preStop command shuts down nginx gracefully. This is helpful if the Container is being terminated because of a failure.Create the Pod:kubectl apply -f https://k8s.io/examples/pods/lifecycle-events.yaml Verify that the Container in the Pod is running:kubectl get pod lifecycle-demo Get a shell into the Container running in your Pod:kubectl exec -it lifecycle-demo -- /bin/bash In your shell, verify that the postStart handler created the message file:root@lifecycle-demo:/# cat /usr/share/message The output shows the text written by the postStart handler:Hello from the postStart handler DiscussionKubernetes sends the postStart event immediately after the Container is created. There is no guarantee, however, that the postStart handler is called before the Container's entrypoint is called. The postStart handler runs asynchronously relative to the Container's code, but Kubernetes' management of the container blocks until the postStart handler completes. The Container's status is not set to RUNNING until the postStart handler completes.Kubernetes sends the preStop event immediately before the Container is terminated. Kubernetes' management of the Container blocks until the preStop handler completes, unless the Pod's grace period expires. For more details, see Pod Lifecycle.Note:Kubernetes only sends the preStop event when a Pod or a container in the Pod is terminated. This means that the preStop hook is not invoked when the Pod is


Question: What is Attach Handlers to Container Lifecycle Events?

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


Question: What is Before you begin?

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


Question: What is Define postStart and preStop handlers?

Answer: I n   t h i s   e x e r c i s e ,   y o u   c r e a t e   a   P o d   t h a t   h a s   o n e   C o n t a i n e r .   T h e   C o n t a i n e r   h a s   h a n d l e r s   f o r   t h e   p o s t S t a r t   a n d   p r e S t o p   e v e n t s .   H e r e   i s   t h e   c o n f i g u r a t i o n   f i l e   f o r   t h e   P o d :   a p i V e r s i o n :   v 1   k i n d :   P o d   m e t a d a t a :   n a m e :   l i f e c y c l e - d e m o   s p e c :   c o n t a i n e r s :   -   n a m e :   l i f e c y c l e - d e m o - c o n t a i n e r   i m a g e :   n g i n x   l i f e c y c l e :   p o s t S t a r t :   e x e c :   c o m m a n d :   [ " / b i n / s h " ,   " - c " ,   " e c h o   H e l l o   f r o m   t h e   p o s t S t a r t   h a n d l e r   >   / u s r / s h a r e / m e s s a g e " ]   p r e S t o p :   e x e c :   c o m m a n d :   [ " / b i n / s h " , " - c " , " n g i n x   - s   q u i t ;   w h i l e   k i l l a l l   - 0   n g i n x ;   d o   s l e e p   1 ;   d o n e " ]   I n   t h e   c o n f i g u r a t i o n   f i l e ,   y o u   c a n   s e e   t h a t   t h e   p o s t S t a r t   c o m m a n d   w r i t e s   a   m e s s a g e   f i l e   t o   t h e   C o n t a i n e r ' s   / u s r / s h a r e   d i r e c t o r y .   T h e   p r e S t o p   c o m m a n d   s h u t s   d o w n   n g i n x   g r a c e f u l l y .   T h i s   i s   h e l p f u l   i f   t h e   C o n t a i n e r   i s   b e i n g   t e r m i n a t e d   b e c a u s e   o f   a   f a i l u r e .   C r e a t e   t h e   P o d :   k u b e c t l   a p p l y   - f   h t t p s : / / k 8 s . i o / e x a m p l e s / p o d s / l i f e c y c l e - e v e n t s . y a m l   V e r i f y   t h a t   t h e   C o n t a i n e r   i n   t h e   P o d   i s   r u n n i n g :   k u b e c t l   g e t   p o d   l i f e c y c l e - d e m o   G e t   a   s h e l l   i n t o   t h e   C o n t a i n e r   r u n n i n g   i n   y o u r   P o d :   k u b e c t l   e x e c   - i t   l i f e c y c l e -


Question: What is Discussion?

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


Question: What is What's next?

Answer: L e a r n   m o r e   a b o u t   C o n t a i n e r   l i f e c y c l e   h o o k s . L e a r n   m o r e   a b o u t   t h e   l i f e c y c l e   o f   a   P o d .


Question: What is Reference?

Answer: L i f e c y c l e C o n t a i n e r S e e   t e r m i n a t i o n G r a c e P e r i o d S e c o n d s   i n   P o d S p e c