ES and LUN

Elastic Stack Elasticsearch
1

I have a 6 node cluster(6.8.5). I need to change the storage and therefore the LUN of my linux server for three nodes. I am thinking to follow the steps:
1- exclude these nodes and shift the shards to the other nodes.
2- stop elasticsearch
3- change the lun of the nodes.
4. restore the cluster settings back and include all the nodes.

Will this be a good way to change the lun and the storage or will this cause any error if the data is mapped to the lun?

2

Your plan is generally sound.

  1. Exclude nodes and relocate shards.
  2. Stop ES on the target nodes (Gracefully stop ES on the nodes you plan to modify.). Ensure the shutdown is complete before proceeding.
  3. change the LUN/Storage (Double check file system permissions and mount options to ensure ES can read and write data).
  4. Restart ES and rejoin the cluster.
3

The issue with your approach is that you will remove exactly half of your nodes and may not have a majority of master eligible nodes available. If your cluster is correctly configured this should make the cluster go into red state.

5

I'm planning to change for one node at once.

1 Like