Proxmox Ceph Pool specify disks

[Mike85]

It`s my first time using Ceph on Proxmox.

I have added the Monitors and Manager systems after it added all disks (OSDs, same Size and model) which should be used for ceph to generatign pools.
If I am correct ceph automatically assigns the ODS to the new defined pool?



We are now planing to add additional disks with different diskspace and rw speed, would it be possible to specify a pool which only includes the new disks?

I am using:
ceph version 16.2.7 (f9aa029788115b5df5eeee328f584156565ee5b7) pacific (stable)

 

[itNGO]

Hi, read about "CRUSH-MAP", you can nearly do everything you want for placement.
For example, we have 3-Node-Clusters where only 2 Nodes have OSDs and created Crush-Map which creates 4-Copies on 2 Servers.
But many settings can only be done via command line. The WebGui is very limited here, but that's ok. You should know what you are doing, when working with CEPH.

 

[Mike85]

Thanks, I will ceck it.

 

[zeuxprox]

Hi,

In my cluster I have 2 pools, one for NVMe disks and one for SSD disks. These are the step that I followed to achieve my goal:

Create 2 rules, one for NVMe and one for SSD:
ceph osd crush rule create-replicated <rule-name> <root> <failure-domain> <class>

So for NVMe disks the above command is (nvme_replicated is the name of my rule for NVMe disks, you can change it...) :
ceph osd crush rule create-replicated nvme_replicated default host nvme

Instead for SSD disks the command is (ssd_replicated is the name of my rule for SSD disks, you can change it...) :
ceph osd crush rule create-replicated ssd_replicated default host ssd

Now in the GUI you have to create 2 pools, one associated to the rule nmve_replicated (for NVMe disks) and one assiaceted to the rule ssd_replicated (for SSD disks). Finally, in each node, you have to associate each OSD to one class (nvme or ssd).

 

[Mike85]

Thanks a lot, I will try it.

One more question where or how do I associate each OSD to a class?

 

[zeuxprox]

Thanks a lot, I will try it.

One more question where or how do I associate each OSD to a class?

In the last step in the Gui, in each node under Ceph --> OSD, when you add OSDs to Ceph...

 

[Mike85]

Thanks, worked for me.

Thas what I did:

#Create new class
ceph osd crush class create ssd01


#move osd to device
ceph osd crush rm-device-class osd.X
ceph osd crush set-device-class ssd01 osd.X


#create crush rule
ceph osd crush rule create-replicated ssd01 default host ssd01


# create pool 3/2 via GUI or CLI


# Assign the new crush rule to that pool
ceph osd pool set ceph-vm01 crush_rule ssd01