Traffic not received at the VM

HQuest

New Member
Jul 31, 2025
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0
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I have set up a simple network in Proxmox as follows: physical interface > bond0 (LACP) > vlan401 > vmbr401 > VM net1 (vrtio; untagged).

Code:
auto enp6s0
iface enp6s0 inet manual
        mtu 9000

auto bond0
iface bond0 inet manual
        bond-slaves enp6s0
        bond-miimon 100
        bond-mode 802.3ad
        bond-xmit-hash-policy layer2
        mtu 9000

auto vmbr401
iface vmbr401 inet manual
        bridge-ports vlan401
        bridge-stp off
        bridge-fd 0
        mtu 9000

auto vlan401
iface vlan401 inet manual
        mtu 9000
        vlan-raw-device bond0

If I tcpdump any interfaces on the Proxmox side, I see broadcast/multicast/unicast packets. If I tcpdump inside the VM on net1 interface, I only see broadcast/multicast packets. There is no firewall active at all within Proxmox or inside the guest OS. This behavior is the same on multiple Linux guests of different distros. However, I do see unicast traffic on different VLANs below 255.

What am I missing?
 
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