Replicas count in a helm chart

[jurim76]

Hello

The helm chart has a condition "if statefulset replica count == 4; then create 4 rustfs{0...3} subdirs in /data".
Is it ok, if I want to use 4 sts replicas pods on a different nodes (using podAntiAffinity) and use only /data directory (and one PVC per replica) on every pod?

[majinghe]

@jurim76 Currently, rustfs helm chart support two mnmd type: 4 pods and each pod has 4 pvc, 16 pod and each pod has 1 pvc, total disks(pvc) is 16. If you want to use 4 sts replicas with each pod has 1 pvc, you should modify the helm chart,

    {{- if eq (int .Values.replicaCount) 4 }}
    {{- range $i := until (int .Values.replicaCount) }}
    - metadata:
        name: data-rustfs-{{ $i }}
      spec:
        accessModes: ["ReadWriteOnce"]
        storageClassName: {{ $.Values.storageclass.name }}
        resources:
          requests:
            storage: {{ $.Values.storageclass.size}}
    {{- end }}
    {{- else if eq (int .Values.replicaCount) 16 }}
    - metadata:
        name: data
      spec:
        accessModes: ["ReadWriteOnce"]
        storageClassName: {{ $.Values.storageclass.name }}
        resources:
          requests:
            storage: {{ $.Values.storageclass.size}}
    {{- end }}

the right configuration will be as below and there is no if condition, because 4 pods and 16 pods are same.

    - metadata:
        name: data
      spec:
        accessModes: ["ReadWriteOnce"]
        storageClassName: {{ $.Values.storageclass.name }}
        resources:
          requests:
            storage: {{ $.Values.storageclass.size}}

By the way, you also need to change the configmap

RUSTFS_VOLUMES: "http://{{ include "rustfs.fullname" . }}-{0...3}.{{ include "rustfs.fullname" . }}-headless:9000/data/rustfs{0...3}"

Above configuration should be

RUSTFS_VOLUMES: "http://{{ include "rustfs.fullname" . }}-{0...3}.{{ include "rustfs.fullname" . }}-headless:9000/data"

[majinghe]

/cc @loverustfs

[majinghe]

If possible, we strongly recommend 4 pods and each has 4 pvc, due to a better data security.

[jurim76]

@majinghe
Do we really need to keep this hardcoded schema with 4 or 16 pods only?
What happened if I want to use 8 pods or 32 pods?
Let's make it simpler - use 4 replicas with 4 or 1 PVC per replica or use > 4 replicas with 1 PVC per replica
Also I will prepare the PR with 4 replicas with 1 PVC per replica support

[HaveFun83]

Any news here?

The docs show something like

A minimum of 4 servers is required, with each server needing at least 1 disk to safely start a distributed object storage cluster.

So 4 replicas with one pvc per replica should be sufficient?

[harrytang]

Any updates so far ? 🙂