Shard allocation filtering for replications

Elastic Stack Elasticsearch
1

Hi i was wondering if there was a way to route replicas to specific nodes in a cluster in the same way you can do shards with the allocation filtering. ??

My scenario is : I have a server with two blades in - each blade runs a couple of nodes - all of it clustered together.
I want to configure all my indexes to allocate Only on nodes on bladeA ...and all replications only to allocate on nodes on bladeB - so that I can lose a blade and still have a full set of data available.

If each blade was running just one node , ES would automatically allocate it as such - but it doesnt really help me if bladeA:node1 replicates to bladeA:node2 (Well, not for redundency)

Regards

2

It sounds like you want Cluster-level shard allocation and routing settings | Elasticsearch Guide [8.11] | Elastic :

You can use custom node attributes as awareness attributes to enable Elasticsearch to take your physical hardware configuration into account when allocating shards. If Elasticsearch knows which nodes are on the same physical server, in the same rack, or in the same zone, it can distribute the primary shard and its replica shards to minimise the risk of losing all shard copies in the event of a failure.

3

Ah - looks like Exactly what I want !
Thanx. Will try it out - once I actually get my cluster up :smiling_face_with_tear: