I am having an issue with Proxmox and ARP changing the MAC address of virtual machines.
arp -a returns:
ipxxx.ip-51-89-201.eu (51.89.201.xxx) at fe:ed:de:ad:be:ef [ether] on vmbr0
This virtual machines MAC should not be that. Rebooting (the virtual machine) or flushing ARP cache fixes it temporarily.
The MAC fe:ed:de:ad:be:ef (feed dead beef) is a sign of someone flooding the network with a gratuitous arp? 51.195.234.254 is the gateway address on the machine
? (51.195.234.254) at fe:ed:de:ad:be:ef [ether] on vmbr0
Proxmox node /etc/network/interfaces
auto lo
iface lo inet loopback
auto enp193s0f0
iface enp193s0f0 inet manual
auto enp133s0f0
iface enp133s0f0 inet manual
auto enp133s0f1
iface enp133s0f1 inet manual
auto enp193s0f1
iface enp193s0f1 inet manual
iface enp9s0f3u2u2c2 inet manual
auto bond0
iface bond0 inet manual
bond-slaves enp193s0f0 enp193s0f1
bond-miimon 100
bond-mode 802.3ad
bond-xmit-hash-policy layer2+3
auto bond1
iface bond1 inet manual
bond-slaves enp133s0f0 enp133s0f1
bond-miimon 100
bond-mode 802.3ad
bond-xmit-hash-policy layer2+3
auto vmbr0
iface vmbr0 inet static
address 51.195.234.xxx/24
gateway 51.195.234.254
bridge-ports bond0
bridge-stp off
bridge-fd 0
post-up ip route add 51.89.201.xxx/28 dev vmbr0
post-up echo 1 >/proc/sys/net/ipv4/ip_forward
I have tried adding the following but it hasn't done much
net.ipv4.conf.vmbr0.arp_ignore=1
net.ipv4.conf.vmbr0.arp_announce=2
The only temporary fix I know now is to clear the current ARP cache
ip -s -s neigh flush all
