[pve-devel] [PATCH manager 2/2] pve6to7: storage content: ignore misconfigured unreferenced volumes

[Thomas Lamprecht]

On 08.07.21 09:29, Fabian Grünbichler wrote:
> On July 7, 2021 12:22 pm, Fabian Ebner wrote:
>> If the same local storage is configured twice with content type
>> separation, migration in PVE 6 would lead to the volumes being
>> duplicated. As that would happen for every migration, such an issue
>> would likely be noticed already, and in PVE 7 such configuration is
>> not problematic for migration anymore. Also, misconfigured
>> unreferenced volumes are not an issue with respect to the upgrade
>> itself, just drop the check.
> 
> but those checks also catch storages that are misconfigured for which no 
> such inverse storage with opposite content type and otherwise identical 
> settings exists? we can't just drop them altogether?
> 
> we COULD skip them conditionally for storage pairs (same type, same 
> 'path'/pool/pool+mons/.., one with images on with rootfs), but such 
> setups are still wrong and not properly separated IMHO. and stuff like 
> dir-storage on-top of other dir-like storage with volumes stored in the 
> same path are not really "detectable" in a reliable and cheap fashion 
> and should really be fixed by the user (e.g., by moving the dir storage 
> into a non-confusable sub-dir of the backing storage).

as long as the content types are non-overlapping it is separated though,
a user in the forum had a GlusterFS entry used by QEMU directly and that
GlusterFS mounted on the system for containers, both added as storage but
strictly separating content types.

I.e., an OK setup where changing anything could actually lead to breakage,
but the warning as it was did not really reflect that. If that can be
improved then OK, but as is it was just not worth for what I perceive as
rather small in-practice risk of that change.