Pve cluster upgrade 8.4 to 9.2 adding pve-entreprise subscription

[Valombre]

Hello,

I’m writing this post to best prepare for the migration of my cluster of two Proxmox 8.4 servers to the latest version, 9.2 (no ceph)

I’m carefully reviewing the procedure at https://pve.proxmox.com/wiki/Upgrade_from_8_to_9

For your information, I already migrated from version 7 to version 8 some time ago on same hardware.

The difference this time is that I’m in the process of acquiring licenses to upgrade to the Enterprise version.

Goal: to have a minimum level of official license support and gain access to the pve-entreprise repositories for greater stability.

My questions regarding this critical upgrade (already behind schedule, as end-of-support for version 8 is August 31, 2026):

1) Is it better to enable the pve-enterprise repository on version 8 Bookworm (by updating to the latest packages and then rebooting) and then perform the upgrade procedure to version 9 pve-enterprise, followed by another reboot?

Or

Should I install the missing Version 8 updates (with a reboot) on pve-no-subscription, then perform the upgrade procedure and, at that point, switch to the pve-entreprise Version 9 repository instead of the pve-no-subscription Version 8 repository?

2) For safety’s sake (in addition to backups), I plan to move my VMs and LXCs via replication/migration to one of the servers running version 8 before the upgrades/reboots, then upgrade the other server to version 9, migrate all VMs/LXCs to the version 9 server, and finally upgrade the second server from version 8.

Question: Is this the safest method, and is there another option?

3) How long can I reasonably delay the second part of the upgrade from version 8 to 9 ? Basically, is there a risk that the replication/migration of the VMs/LXCs will no longer work if I wait a few days (2–3), given that my goal is to verify the stability of version 9 on my hardware (I don’t have any spare hardware and i do that for my normal kernel upgrades since version 7.x ) ?

Thank you in advance for sharing your experiences and insights on this topic.

 

[leesteken]

The enterprise repository is always a little behind (or equal) and never ahead of the no-subscription. There is no reason to enable the enterprise repository on the old version as it will not give you newer updates than no-subscription.
Make sure you have a QDevice when running only two nodes, because one never has quorum without it when the other is turned off (temporarily).
PVE 8 and its kernel versions are out of support, so you should upgrade now to get some important security updates. Or not, it's your choice between various different kind of risks.

 

[VictorSTS]

You don't specify which packages you have on PVE8 at the moment.

A safe path is:

• Activate subscription now on PVE8.
• apt update && apt dist-upgrade
  • If you already have latest packages for PVE8 from no-subscription, few or no packages will be installed.
• Pin your nic's names pve-network-interface-pinning generate.
• Reboot.
• Follow the official PVE8to9 procedure.
  • As you already have subscription active, you'll install PVE9 from Enterprise repo (this is the main reason why I recommend enabling it on PVE8).

As mentioned above, remember that in a 2 node cluster, if one is down the other has no quorum, /etc/pve goes readonly and you can do almost nothing besides shutting down VMs/LXC. If HA is enabled, the surviving node will fence itself, resetting itself and taking down all resources with it.

 

[Valombre]

Hello,
thanks for you answers, i will do my best to install and configure a Qdevice before the upgrades.

Any clues about the question 3) ?

3) How long can I reasonably delay the second part of the upgrade from version 8 to 9 ? Basically, is there a risk that the replication/migration of the VMs/LXCs will no longer work if I wait a few days (2–3), given that my goal is to verify the stability of version 9 on my hardware (I don’t have any spare hardware and i do that for my normal kernel upgrades since version 7.x ) ?

 

[leesteken]

A good time to do that would have been when PVE 9.0/9.1/9.2 was first released and 8.4 was still in support. You are now very much behind in security updates, but which is more important (or risky) for you is eventually up to you to decide.

 

[sterzy]

To add to what leesteken said, you should also not rely on a cluster that is split between two different PVE versions for too long. Note that we try our best to support live migrations of guests from an older PVE version to a newer one, but not the other way round. So if you need to migrate guests from a PVE 8 host to a PVE 9 host, that is fine. Should something happen that makes a migration in the other direction necessary there are no guarantees that this will work.

As for replication, I am not aware of any specific issues that would break that, but again, there are no guarantees here.