Proxmox Ceph Cluster with SATA drives

[mkokani]

Dear Experts,

Need you valuable inputs on below queries.

Current Cluster Setup : Hyper-Converged Ceph Cluster

Dell R630 * 9 with all flash SSD's --> Will be creating Ceph pool for storage purpose.

Future addition :
Dell R730 *3 with SATA drives -->

Query to experts is can we expand the existing Ceph cluster with new different model H/W , SATA drives and create separate Ceph pool using only SATA drives.
If yes please suggest your inputs and if not what will be the bottle neck/Limitation for that.

Thanks & Regards
mkokani

 

[Alwin Antreich]

Query to experts is can we expand the existing Ceph cluster with new different model H/W , SATA drives and create separate Ceph pool using only SATA drives.
If yes please suggest your inputs and if not what will be the bottle neck/Limitation for that.

Yes, you can. The disks need to be distributed evenly across the nodes. And the slowest disk for a pool will determine the performance of the cluster.

 

[mkokani]

Yes, you can. The disks need to be distributed evenly across the nodes. And the slowest disk for a pool will determine the performance of the cluster.

Thank you Alwin for your Input, Can you share your more insights on " slowest disk for a pool will determine the performance of the cluster", is that overall cluster performance will be down with introducing SATA disks.

 

[Alwin Antreich]

Thank you Alwin for your Input, Can you share your more insights on " slowest disk for a pool will determine the performance of the cluster", is that overall cluster performance will be down with introducing SATA disks.

Ceph allows to use device class based rules. If a pool uses such a rule, the slowest disk of that device class will determine the overall performance of that pool. With the default rule (replicated_rule) it will be the whole cluster.
https://pve.proxmox.com/pve-docs/chapter-pveceph.html