VLAN for Proxmox and VMs -- VM not getting an IP

[Bastian987]

Hi,

Im new to Proxmox and I'm lost on the VLAN setup despite quite some reading :
I have created a new VLAN "4" on my Unifi controller (on a Dream machine), this VLAN 4 is configured to not use DHCP. I assigned VLAN 4 to the the switch port the Proxmox VE hardware is connected to. Finally, I used a static IP for the Proxmox VM, 192.168.4.40. So far, this setup is working.

As a last step, I activated 'VLAN aware' in the Proxmox GUI for the network. The interfaces file looks like this

auto lo
iface lo inet loopback

iface enp86s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.4.40/24
        gateway 192.168.4.1
        bridge-ports enp86s0
        bridge-stp off
        bridge-fd 0
        bridge-vlan-aware yes
        bridge-vids 2-4094

iface wlo1 inet manual

Now I tried to spin up a home assistant OS VM. However, the new VM does not seem to get a IP. My assumption: the new container expects to get a IP from DHCP, but the machine in the VLAN 4 does not have a DHCP.

How can this problem be solved?

I see two options:
- give also each VM a static IP address manually
- assign VMs the default VLAN 1 to get it to the default VLAN with active DHCP

Is that correct? I tried to go the second path and added "tag=1" to network of the HA VM. I assume that overwrites the setting I made for the switch port of the dream machine. However, the HA VM does still not get an IP address.

Any advice how to solve that issue as a beginner in the topic?

 

[MarkusKo]

if you want dhcp you can set your vm's network to be on another vlan that has dhcp




in general i would use static ip's for something like that - you want your services to have a static ip, especially if other devices access it.

 

[Bastian987]

Thanks for your reply! I have set this VLAN tag. But the HA VM still did not get an IP. Then, I changed the configuration of the switch port from network with VLAN 4 to 'NONE' in my Unifi controller. Now the HA VM spins up and gets an 192.168.1.x IP address. However, I can then no longer access Proxmox on 192.168.4.40

 

[MarkusKo]

switch ports have a native (untagged) vlan and a tagged vlan
proxmox uses by default the native vlan (in your case vlan 40), if you set a vlan on your vm then proxmox "tags" the traffic with a vlan header and the switch will filter the traffic to that specific vlan. you can try to add vlan 1 as tagged vlan on that switch port but i'm not sure if unifi will let you do that because vlan 1 is somewhat "special"

 

[Bastian987]

ah, I see. How about that approach, as I want to have my VMs in the vlan 1: I remove the native vlan in Unifi to do all IP / vlan assignments in proxmox:

auto lo
iface lo inet loopback

iface enp86s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.1.3/24
        gateway 192.168.1.1
        bridge-ports enp86s0
        bridge-stp off
        bridge-fd 0

auto vmbr0.4
iface vmbr0.4 inet static
    address 192.168.4.40/24
    gateway 192.168.4.1

That should expose the Proxmox VE as 192.168.4.40, to have a static IP outside of any DHCP (I have read that's a recommendation to have). All VMs I will create can use the vmbr0 interface to get an IP assigned by DHCP in the 192.168.1.3/24 range.

Could that work and makes sense?

Edit: updated the code, address removed in vmbr0 and gateway added in vmbr0.4

 

[MarkusKo]

you should set a gateway for vmbr0.4 otherwise you cant connect to the internet with proxmox (no updates)

remove the gateway and ip address from vmbr0, you don't need an ip address on a vlan aware bridge if only your vlan tagged vm's will use it
in general you should only assign one gateway otherwise you get connectivity issues

 

[Bastian987]

That's the setting I use now:

auto lo
iface lo inet loopback

iface enp86s0 inet manual

auto vmbr0
iface vmbr0 inet static
        bridge-ports enp86s0
        bridge-stp off
        bridge-fd 0
        bridge-vlan-aware yes
        bridge-vids 2-4092

auto vmbr0.4
iface vmbr0.4 inet static
    address 192.168.4.40/24
    gateway 192.168.4.1
iface wlo1 inet manual

 

[MarkusKo]

does everyting work as expected?
proxmox webui reachable via 192.168.4.40?

 

[Bastian987]

initial test: Proxmox available at 192.168.4.40, home assistant OS VM gets an IP in vlan 1 and is accessible as well => looks good to me, thanks a lot for your help!