Using Separate Ethernet Ports for Each VM

bannteagann

Member
Jan 11, 2020
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The goal is to have one node running Proxmox VE 6.1 hosting 4 VMs (Debian 10/Ubuntu 18) each utilizing one of the 5 physical ethernet ports (2 NICs). Setting all VMs to vmbr0 (NIC1) on enp3s0 works, but when I create a virtual bridge for each ethernet port (NIC2), no VM can be pinged from outside the host, nor do the VMs have internet access. Neither DHCP or manually configuring network settings within the VM works. I can't determine if I'm setting up the bridges wrong, or just going about this totally wrong. All ethernet ports on NIC2 show active and when assigned an IP address in webUI can be pinged. The appropriate bridges have also been changed under each VM's hardware tab.

Current /etc/network/interfaces for the host.

auto lo
iface lo inet loopback

iface enp3s0 inet manual

auto enp7s0f0
iface enp7s0f0 inet manual

auto enp7s0f1
iface enp7s0f1 inet manual

iface enp8s0f0 inet manual

auto enp8s0f1
iface enp8s0f1 inet manual

auto vmbr0
iface vmbr0 inet static
address 192.168.33.100
netmask 255.255.255.0
gateway 192.168.33.1
bridge-ports enp3s0
bridge-stp off
bridge-fd 0

auto vmbr1
iface vmbr1 inet manual
bridge-ports enp7s0f0
bridge-stp off
bridge-fd 0

auto vmbr2
iface vmbr2 inet manual
bridge-ports enp7s0f1
bridge-stp off
bridge-fd 0

auto vmbr3
iface vmbr3 inet manual
bridge-ports enp8s0f0
bridge-stp off
bridge-fd 0

auto vmbr4
iface vmbr4 inet manual
bridge-ports enp8s0f1
bridge-stp off
bridge-fd 0

Any assistance would be greatly appreciated.
 
Last edited:
No expert, but don't you need to set the "iface vmbr[1-4] inet" to static not manual and give them an address on the local subnet 192.168.133.xxx so that they see the same gateway, so the guests can get the DHCP and DNS from the gateway?
 
Thanks for the response YellowShed.

I changed the host's /etc/network/interfaces for vmbr1 to what's listed below.
Set the VM's network device to vmbr1
Statically assigned 192.168.33.102/24 to the VM. Then tried again setting the VM to DHCP/auto.

auto vmbr1
iface vmbr1 inet static
address 192.168.33.101
netmask 24
bridge-ports enp7s0f0
bridge-stp off
bridge-fd 0

Unfortunately I still cannot ping to or from the VM. vmbr1 can be pinged.
 
the other bridges don't necessarily need an IP address. They are basically a software version of a switch.
So you set the network interface of the VMs to the according bridges, configured the network inside the VM and still cannot reach anything?

On a hunch I would remove the auto enp7s0f1 parts in your Proxmox network config, reboot and see if it works.
Obviously that goes for all the interfaces that are used with bridges.
 
I set all ethernet ports to "iface enpXXX inet manual" but the problem still persists.
Also tried switching the Network Device Model from VirtIO to Intel, etc. same problem.

It was worth a shot though, thanks.
 
I’ve had the same problem and have tried every which way to get the interfaces to work In the way the OP describes. Nothing seems to work except setting the first interface to bridge and then not using the second interface. Kind of frustrating because I want to assign dedicated interfaces to certain VMs or containers.
 

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