[SOLVED] Ceph configuration question

[starkruzr]

Hi gang,
I'm trying to figure out how pools work in Ceph, and trying to figure out what the best configuration of the devices I have would be. I have three machines in my homelab, and between them I have 3 NVMe 1TB drives, six 512GB spinning drives and six 256GB SATA3 SSDs. I'm trying to puzzle out what the best configuration for these would be. Proxmox was a little opaque in terms of helping understand what kind of configurations were available.

I have no data stored in my current Ceph installation so I can completely redo it if necessary, but I was wondering if something like, "one pool is the 3 1TB NVMes plus 3 of the SATA SSDs, and the other pool is the 6 spinning disks plus 3 of the SATA SSDs used as DB/WAL devices" makes sense or even is possible, the idea there being "one volume oriented around performance and the other around capacity."

But upon reading more of the documentation, I think my understanding of "pools" as "separate storage volumes" is wrong. Can someone help me put this together?
Thanks.

 

[Alwin]

Proxmox was a little opaque in terms of helping understand what kind of configurations were available.

In what sense and where?

But upon reading more of the documentation, I think my understanding of "pools" as "separate storage volumes" is wrong. Can someone help me put this together?

What do you mean by separate volumes?

The Ceph Architecture guide is always a good point to start.
https://docs.ceph.com/docs/nautilus/architecture/#about-pools

 

[starkruzr]

So I figured this out -- basically, to do what I wanted, I needed to create new CRUSH rules on the command line such that the storage classes I wanted were separated out, like so (except I didn't do the tiering): http://tacoisland.net/2019/01/06/hyperconverged-hybrid-storage-on-the-cheap-with-proxmox-and-ceph/