[pve-devel] [PATCH] run-env: fallback to all zero mac for interfaces without

[Thomas Lamprecht]

Am 11.07.25 um 12:03 schrieb Christian Ebner:
> On 7/11/25 11:47, Christoph Heiss wrote:
>> On Fri Jul 11, 2025 at 11:14 AM CEST, Thomas Lamprecht wrote:
>>> Am 11.07.25 um 10:27 schrieb Gabriel Goller:
>> [..]
>>>> To be honest I'd rather filter out this interface. A zeroed out mac is
>>>> reserved for loopback interfaces and usually isn't routed.
>>>
>>> It's not like we set the MAC to zero, rather it's just used for displaying.
>>> This way an admin can at least see the interface and select it for usage,
>>> even if they then need to correctly configure it manually after installation
>>> to make it actually work.
>>>
>>> That said, as manual intervention is required either way, filtering out
>>> might be OK, but your arguments here are IMO not justifying why that route
>>> should be chosen. FWIW, a third alternative might be that the rust
>>> implementation might also just have to learn to not expect a MAC...
>>
>> FWIW, there's also been a Bugzilla report a few days about this problem
>> [0].
>>
>> I've took a cursory glance at going about the third route here, although
>> didn't really get to write much code due to other, more pressing things.
>>
>> If anyone wants to pick that up, short summary w.r.t the Rust part:
>>
>> - It's mostly about doing a `String` -> `Option<String>` conversion for
>>    `proxmox_installer_common::setup::Interface`, the MAC address from
>>    that is then only ever used the post-hook.
>> - There's also `proxmox_auto_installer::sysinfo::NetdevWithMac`, which
>>    tries to read the MAC address from /sys/class/net.
>>
>> [0] https://bugzilla.proxmox.com/show_bug.cgi?id=6508
> 
> Okay, can have a look at this too, but do feel free to beat me to it! 
> Not so familiar with the installer codebase and this smells like having 
> some regression potential.

Yeah, maybe, that's why simply falling back to some "unknown"-like value
sounded promising to me. If we do not have any parsing/checks for the MAC
value, we could indeed fall back to a literal "unknown", then it would be
noticed if we try to use it (e.g., for interface link name-pinning in the
installer)

btw. what does the interface looks like, does it really have no MAC
in the ip link output?