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I have a StatefulSet-1 running with 3 replicas & each pod writing logs to its own persistent volume say pv1,pv2,pv3 (achieved using volumeClaimTemplates:)

I have another StatefulSet-2 running with 3 replicas & I want each POD of StatefulSet-2 access already created StatefulSet-1's volumes i.e. pv1,pv2 & pv3 for processing seperate logs written by each pod of StatefulSet-1.

So pv1,pv2,pv3 should be using by both StatefulSet1 & StatefulSet2 since pv1,pv2,pv3 created as part of StatefulSet-1 deployment! pv1,pv2,pv3 will ofcourse takes POD's name of StatefulSet-1 which is ok for StatefulSet-2.

How to configure StatefulSet2 to achieve the above scenario? please help!

Thanks & Regards, Sudhir

sudhir tataraju
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    Would the [following](https://cloud.google.com/kubernetes-engine/docs/how-to/persistent-volumes/preexisting-pd#using_a_preexisting_disk_in_a_statefulset) help? – dany L May 13 '20 at 18:19
  • no @danyL in the above link we cannot link pvc with a different name. – sudhir tataraju May 14 '20 at 07:10
  • Could you provide your configuration files (YAMLs/JSON) of statefulsets, pvc, pv? How many nodes are you using in your cluster? What GKE version are you using? Did you create your own storageclass or you are using default provided by GKE? Could you share output of `kubectl get pv,pvc`? – PjoterS May 14 '20 at 15:18
  • @PjoterS i didnt create any am looking for approach so nothing there to share but yes storage will be GCP everything of GKE . – sudhir tataraju May 14 '20 at 15:25

1 Answers1

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This won't work. 1. PVs backed by GCE disks are in readWriteOnce mode so 1 pvc per pod. 2. You are achieving the statefulset pods with PVCs using PVC templates which rely on dynamic volume provisioning to create the appropriate PVs and PVCs.

If you need these pods to share the PVC, your best bet is to use a readWriteMany PV such as one backed by NFS. You will also need to create the pods of statefulSet-2 manually to have them mount the appropriate PVCs. You could achieve this by creating a single pod deployment for each one.

Something else to consider, can you have the containers of each statefulSet run together in the same pods? Normally this is not recommended, but it would allow them both to share the same volumes (as long as they are not using the same ports)

Patrick W
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