Problems with networking after editing /etc/network/interfaces.


New Member
Jun 5, 2023
Hello. I'm new to Proxmox and I'm trying to resolve my problems with network after editing "/etc/network/interfaces".

I edited manually "/etc/network/interfaces":
auto lo
iface lo inet loopback

iface eno1 inet manual

iface eno2 inet manual

iface eno3 inet manual

iface eno4 inet manual

auto vmbr0
iface vmbr0 inet static
bridge-ports eno1
bridge-stp off
bridge-fd 0

auto vmbr1
iface vmbr1 inet static
bridge-ports eno2
bridge-stp off
bridge-fd 0

auto vmbr2
iface vmbr2 inet static
bridge-ports eno3
bridge-stp off
bridge-fd 0

auto vmbr3
iface vmbr3 inet static
bridge-ports eno4
bridge-stp off
bridge-fd 0

I did "ifreload -a", rebooted a server.

My first interface eno1 in vmbr0 with WEB GUI doesn't work, Firefox says "timeout", can't ping.
This happen until I ping eno2 (vmbr1),
After this eno1 is starting to work, WEB GUI with adress appears.
Eno1 is working for some time, but after some time WEB GUI stops working, says "connection failure" and I must ping again eno2 to "wake up" eno1 and use WEB GUI.
And again and again.

What is happening? Some kind of sleep / hibernation of network cards?

first of all, there is no subnetmask (neither as CIDR or separate entry) in your configuration.

Then, your configuration will cause a lot of problems regarding routing:
  • You can only have one gateway
  • Never give adresses in the same subnet to different interfaces
Your sporadic timeouts are because there is no clear way for your Proxmox Host to answer to incoming packets, because the routing table is all over the place and thus the reply-packages get sent over random interfaces.

Kind regards,
  • Like
Reactions: bobmc
only vmbr0 needs a specific IP address, you can still create a bridge for your extra network interfaces if you like, just don't assign any ip addresses to them. You could still create a VM, attach it to vmbr2 and give the VM an IP of, that would work. Alternatively, you could bond two or more of your ports into one logical unit (link aggregation) if your network switch supports this functionality


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