[Pkg-utopia-maintainers] Bug#983750: Bug#983750: networkmanager: NM takes over slave interfaces of bond

[Michel Meyers]

On 2021-03-01 11:27, Michael Biebl wrote:
> Am 01.03.21 um 10:41 schrieb Andrei POPESCU:
>> Control: reassign -1 network-manager
>> 
>> On Lu, 01 mar 21, 10:00:26, Michel Meyers wrote:
>>> Package: networkmanager
>>> Severity: normal
>>> 
>>> Dear Maintainer,
>>> 
>>> I had a bond configured as described in Example 1 on: 
>>> https://wiki.debian.org/Bonding
>>> 
>>> This morning, my server's bond interface showed down, and its slaves
>>> kept getting removed. After some digging, I found that networkmanager
>>> had gotten installed and a check in nmcli showed that it had taken 
>>> over each of the slave interfaces
>>> while listing bond0 as unmanaged.
>>> 
>>> It appears that NM ignores the "slaves eth0 eth1" directive in
>>> /etc/network/interfaces so unless each of the interfaces is 
>>> specifically
>>> named as in Example 2, NM takes over the slaves, killing the bond.
> 
> If you want to prevent NM to "auto" manage your devices, you could use
> /usr/share/doc/network-manager/examples/server.conf (copy it to
> /etc/NetworkManager/conf.d/)
> 
> 
> Alternative, you can tell NM explicitly which devices it should ignore.
> See man NetworkManager.conf → unmanaged-devices

I don't normally use NM and don't have it installed. It must've gotten 
pulled in as a dependency of some package (my fault for not catching it 
really) and the nightly systemd restart of services then somehow caused 
it to take over.

I have now created [device] sections declaring the slaves as managed=0 
in the NetworkManager.conf (left over after uninstalling NM), but anyone 
with the same config as me making the same mistake of inadvertently 
installing NM will land in the same weird situation where their bond0 
interface is up but not getting its slaves. (I've also started looking 
at specifically declaring the slave interfaces in 
/etc/network/interfaces, but not had success with that so far as it 
stops the bond0 interface from coming up correctly. "Example 2" from the 
docs seems broken here ... more debugging to be done.)

- Michel