K8s PVC with ReadWriteMany in Couchbase Cluster

hi CB Team

I was trying to make POD up and running with below VolumeClaim definition in Yaml file for Couchbase provided Helm Chart .

volumeClaimTemplates:
- metadata:
name: couchbase
spec:
accessModes:
- ReadWriteMany
storageClassName: pure-file
resources:
requests:
storage: 50Gi

As per what I saw is POD up and running fine but the PVC definition has been modified to ‘ReadWriteOnce’ and it didn’t take ‘ReadWriteMany’ . So something is overriding the yaml that is being passed and might be Operator is doing that . So does that mean Couchbase by definition will not allow ReadWriteMany ?
Not sure if that make sense of having cluster pods will read and write on same shared address space in the storage .
Any insights ?

thanks

The underlying storage class doesn’t support ReadWriteMany so it’ll be defaulting to that. As a rule of thumb never use ReadWriteMany as that allows multiple pods to access the same storage, at which point you start to run into split brain problems potentially destroying your data.

Understand …thats what I think … so Couchbase StorageClass not supporting this and I guess Operator is ignoring that correct ? Even I make that in YAML POD is not allowing that so … so this not something done by K8s PVC and Storage .

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