Elasticsearch cluster migration from 7.12 to 8.5

Hi,

we are running an 1 node elasticsearch cluster on 7.12. we want to setup a 3 node cluster on 8.5.
can someone let me know how to migrate the existing indexes to new cluster.

Thanks
Satendra

Hi Satendra,

To upgrade to 8.5, we recommend upgrading to 7.17 first and then using the upgrade assistant. Check out the below links for details:

  1. Upgrade Elasticsearch
  2. Prepare to upgrade from 7.x

Hi Carly,

Thanks for your response.
will mounting the data disk from old cluster (7.12) on new cluster (8.5) not work? since we are setting up a new cluster.

Thanks
Satendra

Depends on if you have depricated fields in your data. 7.17 changed a lot of stuff so its pretty likely that your indices will break without proper precautions.

Thanks Defalt, but reindexing to a 3 node cluster from a single node cluster, will it any impact?

Start by upgrading the single node to 8.5, then add your other nodes in. This won't be a problem :slight_smile:

1 Like

thats also not an option since the current setup with single node is resided on remote location and new 3 node cluster has to be setup in premise.

Then setup your new cluster and do a remote reindex?

will there be any downtime in this case for old cluster?

Yes, you need to switch to the new one at some point and that'll likely not be instantaneous.

thanks a lot. i believe reindexing using this technique on new cluster would not harm to existing indexes on old cluster even if there are any failures in reindexing process.