network does not work for VM after a while, only resolves after changing MAC

dk flag

I have installed pfSense as a KVM guest in a Debian 11 host using libvirt. The host has two interfaces. One is attached to the VM using macVLAN driver, and serves as pfSense's WAN interface. The other is attached to a linux bridge, and serves the LAN (thus the linux bridge has three ports: the actual physical NIC, a tap interface for VM, and one for the host).

Everything works fine at first. However, after a day or two, the VM's tap interface in the linux bridge (LAN side) becomes unresponsive. I can access the host, but not the VM, even after destroying/starting it. The only way to make it work again is to change the MAC address. Then, the VM becomes accessible, until one/two days. I think the amount of network load also affects the timing. In case of very low load, it takes much longer for the VM's tap interface to become unresponsive.

update: I have also tested OVS bridge, and the results are exactly the same.

Brian avatar
gq flag
This sounds like a bug. You should report it.
Mustafa Mohiuodin avatar
dk flag
Yes it is. However, I have not deployed any special configuration. Just basic libvirt, linux bridge/OVS, and pfSense. There are pretty mature ones. It is very unexpected to be a bug.
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