Shard Relocation||ES expansion

Hi Team, Can someone guide us on this.
How to find out the default retention for ES cluster for indices.
also how to check the default on what basis the shards relocation happens.
is it like cluster tries to bring the same number of shards on all the nodes based on number of shards or does it based on the space of the disks on the nodes.

Welcome to our community! :smiley:

What problem are you trying to solve here?

we have 5 node cluster and that nodes have 2 TB space.
each of the node has 1000 shards on each node.

yesterday we have added 6 more nodes(each has 500 GB of space) to make it 11 in total, after the node addition we saw the relocation of the shards took place automatically and this morning we could see they are relocated to new nodes as well (not same number of shards as old nodes).

Problem is as new nodes has less space, they already reached their 85% of the threshold(it seems this is the default threshold).

So would like to know is this the default behaviour that it will try to allocate the same number of shards on all the nodes.

So my earlier questions is related to above ask.

Yes, that is the default.