Installing proxmon on a server with multiple network cards, results in UI not being available some times


New Member
Jul 5, 2023
I am installing proxmox on a server with 2 x 1Gbps network cards, both are active and both are connected to the nework.
During the proxmox installation, I am selecting one of them (as there is no way to select both), setting the IP, hostname, etc, and the installation process completes successfully.

Now the fun begins:
After the restart if I am lucky I will be able to access the UI at the URL provided by proxmox, but about in half of the restarts, the UI console is not available, although nothing changes at the system level.

Digging a bit into the problem, I've noticed the what actuallyis changed at the connection level, in between the restarts after which the UI console works and the ones in which the UI is not available, is the MAC address of my connection. The IP is the same but the 2 networks cards are switching roles, causing this intermitent behavior . So it sounds like proxmox UI is boud to the network interface selected during installation.

My question is: Is there a way to keep both network cards activ and at the same time have the proxmox UI running ?
If you want to use both NICs you could create a bond and assign your IP to that bond. Then the webUi will be available on both NICs.

If you only want to use a single NIC and the names of those NICs are changing names on reboot (PVE will use whatever NIC now is named like the NIC name in /etc/network/interfaces) you could set some naming rules:
Last edited:
I've already tried to create a bond for the 2 NICs but the result was the same. The problem seems to agravate when I have 2 independent proxmox servers (they are not clustered togather) running in the same network. If I stop one of the servers, the problem goes away.
only bond balance-alb or tlb works with regular switch.
of course you cannot have two pve with same local ip in the same time.
It turned out to be a DNS problem. I'm not 100% sure what was causing it becouse I did a couple of things at the same time to fix it: rename the hosts, and changed the DNS server. Thanks!
Last edited:


The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!