Hello,
I have a (for me) weird problem on a bookworm system
rd@h370:~$ inxi -S
System:
Host: h370 Kernel: 6.1.0-23-amd64 arch: x86_64 bits: 64 Desktop: KDE Plasma
v: 5.27.5 Distro: Debian GNU/Linux 12 (bookworm)
rd@h370:~$
It uses bridging network connections with libvirt work unreliable.
I have in /etc/network/interface bridging networks e.g.
iface eno1.2 inet manual
# libvirt VM
auto br2
iface br2 inet dhcp
# Use the MAC address identified above.
hwaddress ether 18:31:bf:52:1b:1c
bridge_ports eno1.2
# If you want to turn on Spanning Tree Protocol, ask your hosting
# provider first as it may conflict with their network.
bridge_stp off
# If STP is off, set to 0. If STP is on, set to 2 (or greater).
bridge_fd 0
to make the interface available for libvirt.
In addition there are non-bridging networks, e.g.
allow-hotplug eno1.4
iface eno1.4 inet dhcp
All of them share the same physical network but defined separate VLANs.
The full /etc/network/interface file of the machine is here https://
bokomoko.de/~rd/Debian/interfaces
That works well for many hours or even days, but at some point in time the
network is suddenly gone, and all network services die.
root@h370:~# ifdown br2
and
root@h370:~# ifup br2
heals the issue immediately. The non-bridging networks don't see the problem.
The problem occurs independently of libvirt running or not.
In the systemd log, the first entry indicating network problems is that the DNS
server switches to another interface. But it could easily be a consequence and
not the cause of the issue:
Aug 28 06:57:54 h370 dhclient[1195]: DHCPREQUEST for 192.168.4.203 on eno1.4
to 192.168.4.1 port 67
Aug 28 06:57:54 h370 dhclient[1195]: DHCPACK of 192.168.4.203 from 192.168.4.1
Aug 28 06:57:54 h370 dnsmasq[2386]: reading /etc/resolv.conf
Aug 28 06:57:54 h370 dnsmasq[2386]: using nameserver 192.168.4.1#53
Aug 28 06:57:54 h370 dhclient[1195]: bound to 192.168.4.203 -- renewal in
18265 seconds.
As a workaround I could probably write a small script, which pings another
network host and restarts the br interfaces, but I would prefer to understand
why the problem occurs at the first place.
Any idea or hint is welcome.
Many thanks
Rainer
--
Rainer Dorsch
http://bokomoko.de/
