Prelimanary thoughts Proxmox + Ceph Upgrading Nodes

[JeanB Brewp]

Hi Folks,

I'm in need of a hypervisor cluster. I've been thinking about using proxmox and ceph for it instead of vmware. I like opensource tech etc.
I was thinking of upgrading when new versions of proxmox and ceph come out. The logical way I think would be move the VMs to the two other nodes, Upgrade. Move the VMs to one node, upgrade the second node. Move the VMs to the newer installs and upgrade the last node. I'm hoping it's that easy... However, I have my doubts, I'd like to make sure that moving from one version to the next is something we can handle without much fuss.

Is my assumption correct? if not, why, and how does one go about upgrading a cluster, from proxmox 4.4 to 5.0 and ceph from one version to next?
I've not used Promox before but I have experience with qemu/kvm.

 

[udo]

Hi,
normaly you can do such updates - but it's depends on the updates. Years ago, with an new qemu-version, you can't use live-migration and must stop the VMs and start on the updated host again... so it's not easy to speak for updates in the future.

I use ceph since some years (if i remember right i started with 0.6x) and all updates runs with an accessible ceph-cluster. But you must update in the right order (read the update notes!). Normaly update the mon's first and the osds after that.

Udo

 

[JeanB Brewp]

Hi,
I use ceph since some years (if i remember right i started with 0.6x) and all updates runs with an accessible ceph-cluster. But you must update in the right order (read the update notes!). Normaly update the mon's first and the osds after that.
Udo

Thanks for your response.

So I am thinking the way work around that would be to have a backup shared storage to add to the cluster. So that if Ceph dies or needs to be upgraded. I can move the VMs to that storage.

I'm just trying to think ahead and prep my team to be able to support this. What are people doing? etc.

 

[alexskysilk]

I'm in need of a hypervisor cluster. I've been thinking about using proxmox and ceph for it instead of vmware.

If I understand you correctly, you do not have an existing infrastructure and are currently evaluating.

I was thinking of upgrading when new versions of proxmox and ceph come out.

Upgradability is never a foregone conclusion. Generally speaking, if this is meant for production use, before even THINKING about upgrading a working environment you do everything in the lab, and once you stop breaking stuff document what you did and follow that procedure. This proceduce will be different depending on the scope of the upgrade. Anything less is asking for pain and sleepless nights.

I use ceph since some years (if i remember right i started with 0.6x) and all updates runs with an accessible ceph-cluster. But you must update in the right order (read the update notes!).

This.

I'm hoping it's that easy.

Its not. it never is. Upgrading should never be taken lightly for a production environment because murphy's law.

how does one go about upgrading a cluster, from proxmox 4.4 to 5.0 and ceph from one version to next?

you read the update instructions. Then you read it again. Then you perform the upgrade as instructed in the lab. Then when it all goes sideways, reset your lab and do it again, paying attention to where you messed up/misread/misunderstood the directions, mistyped something, etc. You take notes. Once you succeed, try to break it for at least a week, and once you're confident that its not completely misconfigured AND that you can do it again, THEN you try it on production.