Is there a way to export index from one cluster and import into another cluster ?
We call it snapshot and restore.
Otherwise we have reindex from remote.
if i copy index from 5.3 cluster into 6.2 cluster will it be fine ?
If the first time you indexed it was a 5.x cluster then yes it should work.
transferring via logstash be faster than remote reindex ? trying to check which one is advantageous
Not sure what role has logstash here.
Do you mean to do the reindex?
I'd personally start a 7.1 cluster and use reindex from remote api to read the 5.x cluster.
If I can use logstash to copy index from one cluster to another cluster ...
Surely but that's the same as using the reindex api.
True. But using the reindex API , we have to make the config change and restart the cluster. However, using log stash we do not require config change and cluster restart. Please clarify.
Valid concern.