Having difficulty setting up a second linux bridge vmbr1 (solved, had to clear virtual mac)


Feb 14, 2022
I have 4 nics in my system, two onboard of the HP Z4 that have bugs and hang under high use. I have added 2 via PCIe card.
I have created a 2nd bridge vmbr1 and assigned one of the new ports enps30f1 as a port to the vmbr1 bridge I don't have an IP address here as I am still doing management through vmbr0. If I take a dummy vm and move it to the vmbr1 bridge I loose network. if I move it back it works.
eno1 is one of the onboard integrated Nics.

enp3s0f1 and enp3s0f0 are the new intel NICs that aren't supposed to not hang.

I had assumed that just flipping vmbr0 to vmbr1 would work?
Thanks in advance!

cat 500.conf
agent: 1
boot: order=scsi0;ide2;net0
cores: 2
ide2: none,media=cdrom
memory: 4096
meta: creation-qemu=7.2.0,ctime=1700786949
net0: virtio=9A:F0:E6:02:07:D4,bridge=vmbr0
numa: 0
ostype: l26
scsi0: PMbackup:500/vm-500-disk-0.qcow2,iothread=1,size=50G
scsihw: virtio-scsi-single
smbios1: uuid=c9f7d6d6-0e87-4dc4-a380-8f0b86f6ff8c
sockets: 1
vmgenid: 1ee18009-bf02-4997-a1be-8b45ff1f0efd

auto lo
iface lo inet loopback

auto eno1
iface eno1 inet manual
    post-up /usr/sbin/ethtool -K $IFACE tso off gro off gso off

iface eno2 inet manual

auto enp3s0f0
iface enp3s0f0 inet manual

auto enp3s0f1
iface enp3s0f1 inet manual

auto vmbr0
iface vmbr0 inet static
    bridge-ports eno1
    bridge-stp off
    bridge-fd 0
    post-up /usr/sbin/ethtool -K $IFACE tso off gro off gso off

auto vmbr1
iface vmbr1 inet manual
    bridge-ports enp3s0f1
    bridge-stp off
    bridge-fd 0
    post-up /usr/sbin/ethtool -K $IFACE tso off gro off gso off
Last edited:
I could be a DA, I wiped out the MAC address in the vmbr1 config and it is working, really, is that it? We seem to be missing a "slam my head" emoji

Was it an arp cache somewhere?


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