We have hosts with both nvme storage and sata storage. Currently we run a single elasticsearch instance on each host and to keep performance up we only use the nvme storage. Now, we would like to start using the sata-disks as well for cold storage, expanding our retention capacity.
Is it possible to start multiple nodes on 1 host, one node serving as warm/hot node with the nvme-storage, and one node serving as cold/frozen node with the sata disks? Would this come at a performance cost?
Yep that works.
Although the nodes have separate storage they will be sharing all sorts of other things (RAM, CPU, network bandwidth, ...) and any of these could be a source of contention. But they often aren't.
Thats great news. So basically the message is: give it a go, it'll probably work without much problems. Thanks, will try it out!
One more thing: We have a platinum license to run 3 nodes (each on its own host). Would starting a secondary frozen-data node on each of those hosts impact our licensing?
If you have a license for 3 nodes, you can run only 3 nodes no matter if they are on the same host or not.
That is not really the answer I was hoping for but totally understandable. Thanks for clarifying.
I would suggest that you reach sales/support, but from my experience on-prem platinum licenses are based on node count, so if you have a license for 10 nodes for example, you can run only 10 nodes.
I'm not sure if it blocks you for spinning up another node or not, but running more nodes than the number you have licensed would be a breach of contract I'm assuming.
I guess it'll be cheaper to just raise nvme-capacity in the existing nodes than to get extra licenses for extra nodes for the sata-storage.