6.11.5 virbr0 disappears when restarting VM Manager

[Sascha_B]

Hello, everyone!

 

I noticed this behavior after putting the libvirt image on a new SSD. I stopped VM Manager, put the share on the new SSD, copied the libvirt file, checked permissions and started VM Manager again.

 

Before restarting the VM Manager or after rebooting the server, it looks like this.

 

virsh # net-list --all
 Name      State    Autostart   Persistent
--------------------------------------------
 default   active   yes         yes
 

virsh # net-edit default

<network>
  <name>default</name>
  <uuid>62eaa0bf-331c-47ac-9189-56a25fa38d2c</uuid>
  <forward mode='nat'/>
  <bridge name='virbr0' stp='on' delay='0'/>
  <mac address='52:54:00:e5:88:d8'/>
  <ip address='192.168.122.1' netmask='255.255.255.0'>
    <dhcp>
      <range start='192.168.122.2' end='192.168.122.254'/>
    </dhcp>
  </ip>
</network>

 

 route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.178.1   0.0.0.0         UG    1004   0        0 br0
10.253.0.2      0.0.0.0         255.255.255.255 UH    0      0        0 wg0
172.17.0.0      0.0.0.0         255.255.0.0     U     0      0        0 docker0
172.31.200.0    0.0.0.0         255.255.255.0   U     0      0        0 br-af3bd9cc0c24
192.168.122.0   0.0.0.0         255.255.255.0   U     0      0        0 virbr0
192.168.178.0   0.0.0.0         255.255.255.0   U     1004   0        0 br0
 

 

When I restart the VM Manager, virbr0 does not start again automatically and the VM are no longer displayed but the following error under VMS

 

Libvirt Service failed to start.

 

This can only be fixed by restarting the Docker Service. After that, the VMs are displayed again, but virbr0 does not start automatically.

 

In the routing table, virbr0 is no longer displayed and all VMs that use this adapter do not start and show the following error:

 

Cannot get interface MTU on 'virbr0': No such device

 

virsh shows the following output

virsh net-list --all
 Name      State      Autostart   Persistent
----------------------------------------------
 default   inactive   yes         yes

 

If I start the adapter manually, everything goes back to normal

 

virsh net-start default
Network default started

virsh net-list --all
 Name      State    Autostart   Persistent
--------------------------------------------
 default   active   yes         yes

 

Even after a server restart everything starts normally. Is this behavior normal?

 

A second question would be, how do I find out what kind of interface this is? -> br-af3bd9cc0c24

Edit: Found it, was an orphan Docker Adapter

 

Thanks in advance, Sascha

zeus-diagnostics-20230119-1221.zip

Edited January 19, 2023 by Sascha_B

[PZ303]

Did you figure this out? I'm running into a similar issue.

[RayCN]

On 2/23/2023 at 1:18 PM, PZ303 said:

Did you figure this out? I'm running into a similar issue.

same problem

need help!

[kennymc.c]

I also have this problem. Possibly it has to do with a DNS server running at the same time via Docker.