Host management network drops when VMs start running.


Jun 18, 2021
I'm experiencing this strange issue on one of my boxes.

My network is configured as follows:
auto eno1 iface eno1 inet manual auto eno2 iface eno2 inet manual auto bond0 iface bond0 inet manual bond-slaves eno1 eno2 bond-miimon 100 bond-mode 802.3ad bond-xmit-hash-policy layer2+3 auto vmbr0 iface vmbr0 inet static address gateway bridge-ports bond0 bridge-stp off bridge-fd 0

I have VMs in the attached to vmbr0.
When the VMs start, they would cause the host management network to lose connection.
The VMs themselves would also become unreachable.

If I split the host management from the VM bridge like so, this work as expected.
auto eno1 iface eno1 inet manual address gateway auto eno2 iface eno2 inet manual auto vmbr0 iface vmbr0 inet static bridge-ports eno2 bridge-stp off bridge-fd 0

PowerEdge R6525
NIC NetXtreme BCM5720 2-port Gigabit Ethernet PCIe
Kernel 5.15.108-1-pve
Proxmox 7.4-16


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