Add OSD's to new Cluster

[Chadlee]

Hi guys,

I had a power outage that caused me to re-image one of the two servers in my ProxMox cluster. After re-imaging I wasn't able to get the monitors or managers to come up. I ended up wiping the monitors/managers.

I now have a new Ceph cluster with new monitors/managers but no pool(s) and no OSD's. That said the osd disks were untouched in this process as they are on separate disks and still mount to /var/lib/ceph/osd.

Is there a way to add the OSD's to this new cluster and use the same pools so I can run the VM that was running on them.

Environment:
Proxmox 5.1
Ceph luminous

 

[wolfgang]

Hi,

Ceph needs min 3 nodes 2 are not enough.

You can add osd without problem to an existing cluster and pool.

 

[Chadlee]

Thanks Wolfgang. I am working on getting a third server very soon.

How would I add the rbd/osd's back?

 

[sg90]

If you lost all your monitor's it's not as straight forward as just adding the OSD's to a new CEPH Cluster as you will have a lost the key's and the metadata of which PG is where and so on.

Unless the data is 100% critical your best to start from fresh, even if you can get an extra server that just act's as a monitor and no OSD's at least protects you from a re-occurrence.