Continuing the discussion on TrueNAS Virtualization Plans for 25.04.2

[Protopia]

@Captain_Morgan

When a new version (fish) is BETA or RC.1 it indicates the whole release is still being validated. Even when it gets to Release, we still recommend using the software Status advice based on a self-assessment.

Software quality improves with large numbers of users/system configs and bug fixes which come in the form of software updates. The nature of TrueNAS software is that it runs on an enormously diverse set of hardware with very diverse use-cases. User skills and expectations also vary widely. Nothing substitutes for mass testing. 25.04 has 80,000+ systems and so we have found most of the significant bugs; some will be fixed in 25.04.2

I agree with everything that you said here. Realistically you can never deliver bug-free software.

@Captain_Morgan

We decided to classify the lack of libvirt KVM as a bug and fix it in 25.04.2 version.

So it wasn’t a mistake to remove it, but rather a bug as a consequence of its removal - and apparently not what the community might actually like to hear i.e. an admission that:

1. It could have been left in in the first place to allow parallel running and users migrating at a time of their choosing; and
2. It should have been left in in the first place to allow parallel running, and thus reduce risk and make life easier for virtualisation users; and
3. It (or similar) will be left in to allow parallel running for at least one major release whenever similar situations occur in the future.

@Captain_Morgan

When we apply “experimental” to a feature. It does mean that the rest of the system is operating as expected. If the feature (instances) is not used, we expect no side effects. We think about 85% of Fangtooth users are not using instances.

If that is the case, then why am I not being recommended to move to 25.04.1 (since I don’t user virtualisation and don’t want to use LXCs)?

I don’t have a pressing need to upgrade, but equally I am pretty confident that I would upgrade successfully, and equally confident that I could revert back again if I had problems. So if you think that it is stable, and I think it is stable enough to upgrade to despite being very risk averse, then why are you not recommending me to go and why are you applying the same criteria to people who do use virtualisation as to those that don’t?

@Captain_Morgan

We always attempt to migrate from previous versions (e.g the transition of Apps from K8s to Docker), but we clearly can’t claim 100% success. Data in host paths has generally always migrated.

However from 25.04 (Fangtooth) Version Notes | TrueNAS Documentation Hub :

Manual Migration Required

Due to configuration incompatibilities between the previous libvirt implementation (TrueNAS 24.10 and earlier) and Incus in TrueNAS 25.04, existing VM configurations do not transfer automatically during the upgrade. However, TrueNAS retains storage zvols, allowing you to manually recreate the previous VM configurations and get them back online.

So

1. “We always attempt to migrate from previous versions” is not true in this case; and
2. Perhaps I mis-understood, but aren’t there driver changes needed too which are not even mentioned? e.g. see GUIDE: How to install/migrate Windows VM to Fangtooth/Incus using Virtio drivers

@Captain_Morgan

In future, we’d like to provide that update advice in the UI…but ironically, it will only help future users not current users getting to that state. Current users have to read the software status page.

I note the language used here. “In future, we’d like to provide that update advice in the UI” is not the same as “In future, we will provide that update advice in the UI”.

And of course, had you listened to the similar complaints/advice/discussions given when EE upgrades were happening, the better “update advice” could indeed have been provided for the EE → FT update - but you didn’t and they weren’t.