How Do I Make A Persistent Volume Accessible to Multiple Kubernetes Pods?

2
votes

I've done quite a bit of research and have yet to find an answer to this. Here's what I'm trying to accomplish:

  • I have an ELK stack container running in a pod on a k8s cluster in GCE - the cluster also contains a PersistentVolume (format: ext4) and a PersistentVolumeClaim.
  • In order to scale the ELK stack to multiple pods/nodes and keep persistent data in ElasticSearch, I either need to have all pods write to the same PV (using the node/index structure of the ES file system), or have some volume logic to scale up/create these PVs/PVCs.
  • Currently what happens is if I spin up a second pod on the replication controller, it can't mount the PV.

So I'm wondering if I'm going about this the wrong way, and what is the best way to architect this solution to allow for persistent data in ES when my cluster/nodes autoscale.

1
elasticsearchgoogle-cloud-platformkubernetes

1 Answers

1
votes

Persistent Volumes have access semantics. on GCE I'm assuming you are using a Persistent Disk, which can either be mounted as writable to a single pod or to multiple pods as read-only. If you want multi writer semantics, you need to setup Nfs or some other storage that let's you write from multiple pods.

In case you are interested in running NFS - https://github.com/kubernetes/kubernetes/blob/release-1.2/examples/nfs/README.md

FYI: We are still working on supporting auto-provisioning of PVs as you scale your deployment. As of now it is a manual process.