MAC keeps changing in arp

[vapour]

I don't think it's related, but why do you have "gateway 192.168.1.1" in vmbr3 ?

Good point. The gateway has been removed from vmbr3 and was added to vmbr0.

Should vmbr3 even be given an IP address? I can still access my firewall, which has the gateway IP, from the LAN.
The same question applies for my DMZ on vmbr2.

The flip-flopping seems to have stopped after I made your suggested change, plus hard coded the MAC address 'hwaddress xx:xx:xx:xx:xx:xx' in /etc/network/interfaces for vbmr0 and created a static DHCP entry for the PVE host.

The issue that still remains is the terrible speed. The max i'm seeing with iperf3 from the PVE Host is 30Mbps on a 500Mbps up-link. Now internally, with a more realistic Iperf3 test, iperf3 -c 192.168.1.1 -P 75 -fg -t 10 , the results are scary slow:

[ ID] Interval Transfer Bitrate Retr
[SUM] 0.00-10.00 sec 1.09 GBytes 0.93 Gbits/sec 3487 sender
[SUM] 0.00-10.01 sec 1.07 GBytes 0.92 Gbits/sec receiver

The test increased Memory by 1%. CPU jumped from 0% to 44%



It's obvious that i'm not lacking resources. But for the speed between VM's to be this slow is concerning.

 

[da-alb]

I have the same issue and I'm not using any kind of bond.

 

[bignay2000]

I am experiencing a similiar issue on Debian 12 Proxmox 8.0.4. I had 2 nics in a load balanceed configuration (balance-rr) that did not perform well. I then changed the networking to 1 nic to vmbr0 and created vmbr1 with the other nic. Even thought my network config is accurate (built by the proxmox 8.0.4 GUI and /etc/network/interfaces looks correct), I am getting PFSense's Arpwatch flip flop alerts...

I think their is a bug where ARP is permanently remembering a old configuration, when its suppose to rebuild cache every 5 minutes.

I ran a arp flush and I am hoping this forces the local arp table to forget the prior load balanced nics...

ip -s -s neigh flush all

 

[bignay2000]

This might be the solution
https://serverfault.com/questions/5...ces-on-the-same-machine-to-flip-flop-their-ip

https://serverfault.com/questions/834512/why-does-linux-answer-to-arp-on-incorrect-interfaces

Update Linux to only reply arp from the nic that matches the MAC Address?

sysctl -w net.ipv4.conf.all.arp_ignore=1
sysctl -w net.ipv4.conf.all.arp_announce=2