I have a box running 24.10. I did not upgrade to 25.04 because I have several VMs, and release notes at the time recommended against upgrading. And apparently upgrading to 25.04 causes loss of virtual machines (is this still the case?).
What is the appropriate upgrade path to 25.10? Ideally I don’t want to lose my virtual machines, is there an upgrade path for them?
I tried looking here at the 25.10 upgrade paths page:
But it seems to suggest that I need to go via 25.04, and if 25.04 doesn’t support my VMs, that doesn’t seem correct.
But maybe my information is dated, I see 25.04.02 has in its release notes: “(Updated for 25.04.2) Reintroduced “classic virtualization” with the [Virtual Machines] feature.”
Does this mean it is now safe for me to upgrade to 25.04 and then 25.10?
There seems to be conflicting information here, not sure which is the current advice.
In TrueNAS 25.04.2 and later, virtual machines are created and appear on the Virtual Machines screen. Legacy VMs created in 25.04.0 or 25.04.1 using the Instances feature and some VMs migrated to those versions from TrueNAS 24.10 continue to function and appear on the Containers screen. Legacy VMs on the Containers screen do not autostart in 25.10 or later.
OK, so does this mean legacy VMs will continue to work in 25.10, but I have to start them manually?
chatgpt suggests that upgrading to 25.04.2 should automatically migrate my VMs. And if this doesn’t work for any reason I should do it manually before upgrading to 25.10. But of course, not chatgpt can really be trusted.
Release notes seem to indicate I should not attempt any migration until I after I install 25.10.
Release notes for 25.04:
You do not need to migrate existing VMs from the Containers screen to the Virtual Machines screen at this time. We are developing additional guidance for these legacy VMs for the TrueNAS 25.10 release.
Release notes for 25.10:
Users with existing VMs on the Containers screen should consider migrating associated zvols to the Virtual Machines screen at this time to ensure compatibility with future TrueNAS releases. For information on migrating your zvol storage volume to a new VM created in 25.10 or later, see Migrating Containers VMs.
What bothers me about this is the “Legacy VMs on the Containers screen do not autostart in 25.10 or later.” - does this mean I can manually start legacy VMs in 25.10? Or that legacy VMs are broken in 25.10 until after I do the migration?
with 25.04.2 the same vm backend got re-enabled that 24.10 uses. There’s literally nothing you have to do. Only if you have had used 25.04.0 or .1 and migrated your existing vms into the “new” incus vm backend you’d have to do any migration at all.
You don’t have to migrate anything. if you jump to the last available version of 25.04
OK, so maybe chatgpt was close to correct. I just upgrade to 25.04, and then I upgrade to 25.10, and the upgrade process should take care of everything?
If an upgrade is not urgent or you are not using smb shares, I’d avoid switching to 25.10 because a fair bit of people, me included are having issues with smb shares which make them practically unusable.
