ceph qestion, sas3 and nvme on separate bucket

[ilia987]

currently i have one ceph poll consists of mix of sas3 ssds , (different models and sizes , but all in the same performance category )

i thinking of creating another bucket (i dont know if bucket is the right name for what i want to do )
currently we have the default (consists of sas3 ssds)


but i would like to add another pack of nvme ssds separated from the existing pool . the pool above is mainly read intensive, and the planed one for write intensive

 

[Alwin]

Then you want pools based on device classes. You will need to create rules for your current pool first.
https://pve.proxmox.com/pve-docs/chapter-pveceph.html#pve_ceph_device_classes

 

[ilia987]

can i do it on existing (running) pool ?

 

[Alwin]

can i do it on existing (running) pool ?

Yes.

If the pool already contains objects, all of these have to be moved accordingly. Depending on your setup this may introduce a big performance hit on your cluster. As an alternative, you can create a new pool and move disks separately.

 

[ilia987]

the pool is very fast (based on high end sas ssds and 40gb network) so a dont think we will have such a big performance hit. worst case the storage will be down for 10 hours (we can do it over night)

currently there are only sas ssds (nvme are not yet connected) will i still have the effect?
can you guide me of the commands needed to do it?

 

[Alwin]

currently there are only sas ssds (nvme are not yet connected) will i still have the effect?

Do the device class based rule for the current pool first. This should introduce minimal rebalance/recovery.

can you guide me of the commands needed to do it?

See the documentation.
https://pve.proxmox.com/pve-docs/chapter-pveceph.html#pve_ceph_device_classes