Multi-Attach error for volume when using more than 1 rocketchat replicas

[TLINDEN]

I wanted to use 3 rocketchat replicas with persistent storage.

This is the relevant part of the values.yaml in use:

persistence:
  enabled: true
  storageClass: "partition-silver"
  accessMode: ReadWriteOnce
  size: "50Gi"

As long as replicas is set to 1 it works. However, when I set it to 3, then it doesn't.

2 Pods are coming up, but the third one gives this error:

event:

Warning  FailedAttachVolume  3m44s  attachdetach-controller  Multi-Attach error for volume "pvc-d59480a9-9d13-408c-964f-94b145e034c5" Volume is already used by pod(s) rocketchat-integration-rocketchat-75d7b7cd44-txw5s, rocketchat-integration-rocketchat-75d7b7cd44-2psmn

pods:

NAME                                                              READY   STATUS              RESTARTS   AGE
rocketchat-integration-rocketchat-75d7b7cd44-2psmn            1/1     Running             0          19m                                                                           
rocketchat-integration-rocketchat-75d7b7cd44-7thmq            0/1     ContainerCreating   0          22m
rocketchat-integration-rocketchat-75d7b7cd44-txw5s            1/1     Running             0          94m

pvcs:

NAME                                   STATUS  VOLUME                                    CAPACITY  ACCESS MODES  STORAGECLASS      AGE   
rocketchat-integration-rocketchat  Bound   pvc-d59480a9-9d13-408c-964f-94b145e034c5  50Gi      RWO           partition-silver  642d

All 3 pods are configured to use the same PVC. I don't know why the 2nd one came up tough. It shouldn't have.

The helm chart should create 3 different PVCs, one for every replica and not share 1 PVC for all replicas.

I am using chart version 6.23.2.

[TLINDEN]

Ok, I further investigated this.

The ReplicaSet is ok as long we only need 1 pod. Once we need more, then it is useles. Especially if we want to use persistent storage.

You should toss the Deployment and replace it with a Statefulset, where we can add a PersistentVolumeClaimTemplate and easily scale to more than 1 pods.