Kubernetes StatefulSet: Difference between revisions

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* [[Kubernetes API Resources Concepts#StatefulSet |API Resources Concepts]]
* [[Kubernetes API Resources Concepts#StatefulSet |API Resources Concepts]]


=Overview=
=TODO=
 
Used for stateful application components, where the application component relies on access to "stable" file storage to maintain state between restarts. As such, [[Kubernetes_Storage_Concepts#local|local volumes]] that are directly attached to node hosts, can be used. A StatefulSet and the individual pods the StatefulSet manages are registered with the [[Kubernetes_Networking_Concepts#The_DNS_Service|cluster's DNS service]].
 
A stateful set makes sure pods are rescheduled in such a way that they retain their [[Kubernetes_Pod_and_Container_Concepts#Pod_Identity|identity]] and [[Kubernetes_Pod_and_Container_Concepts#Pod_State|state]].


The StatefulSet '''creates''' PersistentVolumeClaims in a manner similar to the one in which it creates pods. More details in [[#StatefuSet_Storage|StatefulSet Storage]] below.
{{Internal|Kubernetes StatefulSet TODEPLETE|Kubernetes StatefulSet TODEPLETE}}
 
=StatefulSet Manifest=
{{Internal|Kubernetes StatefulSet Manifest|StatefulSet Manifest}}
 
=StatefulSet Storage=
 
==Persistent Volume Claim Template==
 
Because persistent volume claims map to persistent volumes one-to-one, and each pod of a StatefulSet needs its dedicated, separate storage, each pod of a StatefulSet needs to reference a different persistent volume claim to have its own separate persistent volume. The StatefulSet achieves this behavior by creating persistent volume claims alongside pods, based on a persistent volume claim template.
 
===Labels on a Persistent Volume Claim created from the Persistent Volume Claim Template===
 
When the persistent volume claims associated with the StatefulSet pods are created, each persistent volume claim will automatically get all labels declared in the [[Kubernetes_StatefulSet_Manifest#spec_selector_matchLabels|.spec.selector.matchLabels]] section of the StatefulSet manifes.
 
===Persistent Volume Claim Template Manifest===
{{Internal|Kubernetes_StatefulSet_Manifest#volumeClaimTemplates|StatefulSet Manifest}}
 
=Operations=
{{Internal|Kubernetes StatefulSet Operations|StatefulSet Operations}}
 
=TODO=
* https://medium.com/better-programming/kubernetes-a-detailed-example-of-deployment-of-a-stateful-application-de3de33c8632

Revision as of 20:05, 22 September 2020

External

Internal

TODO

Kubernetes StatefulSet TODEPLETE
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