Migrate elastic search data from one cluster to other

Hi,

We have 3 node elastic search cluster and for certain reason we have to get rid of those VMs, now i need to migrate the data from the existing cluster to new one without a down time.

I thought of adding 3 new nodes to the existing cluster and then shut down the existing nodes one by one. is this a good idea at all?
or
please suggest a best method.

Hi,

Yes, it's the easy way.

1°/ Add new nodes in your cluster, with master eligible and data flags enable.

2°/ Exclude old nodes on by one from the cluster, this will move shards to new nodes:

curl -XPUT 'http://ip-new-node:9200/_cluster/settings?pretty' -H "Content-Type: application/json" -d '
{
"transient" : {
"cluster.routing.allocation.exclude._name" : "name-of-an-old-node"
}
}'

When the old node doesn't have data anymore, you can stop the service and stop the machine !

Repeat 3x for your 3 old nodes.

bye,
Xavier

Thanks a lot, @xavierfacq
One quick question. should i stop logstash from feeding the old ES node? before I do the second step. I am bit confused at that.?

regards
Parvat

Not certain, but it's quite possible that Logstash will see new nodes even if you stop the old. But, I think that you shoud restart your Logstash with new nodes IPS before stopping old nodes.

bye,
Xavier

This topic was automatically closed 28 days after the last reply. New replies are no longer allowed.