Very new to networking and proxmox in general, changed some things in the /etc/network/interfaces and now none of my vms have internet.

[TeenagedLime3]

Hi,
I am unable to access any of my vms outside the proxmox window. None of the vms have internet, and im guessing its to do with the vmbr0 confirguration as I had to add that back after changing the file (see below) but I have no clue what it should be so my vms ips work. Ideally I would not like to have to change the vms static ips since it would mean changing them in a lot of other locations too and it was working fine before. I get that wiping the whole server and reinstalling proxmox would probably fix the issue but im hoping there is a simple fix that wont require that.
Proxmox has internet, however none of the vms do. Doing the ping google.com command gives the "temporary failure in name resolution" error and doing ping 1.1.1.1 gives the "destination host unreachable" error.
I did have a skim read through the proxmox network configuration docs but since I am new to networking I was very confused.

My network setup is running through a custom openwrt router that has the gateway 192.168.1.2. It is running a vpn client, although I assume this isnt relevant.

My proxmox version is 6.0.15-edge

I changed the /etc/network/interfaces file on proxmox a bit to fix a network issue using https://wiki.debian.org/NetworkConfiguration. I deleted the old file since proxmox didnt have internet and added the lines to make proxmox connectable.

auto lo
iface lo inet loopback

auto enp8s0
iface enp8s0 inet static
        address 192.168.1.16/24
        gateway 192.168.1.2
        dns-nameservers 1.1.1.1 1.0.0.1

However, I didnt realise that I would need the vmbr0 bits as well, so I added what I thought was right for the bridge bits however now my vms cannot access the internet, and I cannot access them outside of proxmox.
Here is the full /etc/network/interfaces proxmox file:

auto lo
iface lo inet loopback

auto enp8s0
iface enp8s0 inet static
        address 192.168.1.16/24
        gateway 192.168.1.2
        dns-nameservers 1.1.1.1 1.0.0.1
auto vmbr0
iface vmbr0 inet static
        address 192.168.1.1/24
        gateway 192.168.1.2
        bridge-ports eno1
        bridge-stp off
        bridge-fd 0

here are the interfaces (when I do ip a) on proxmox

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp8s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 0c:9d:92:79:09:a2 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.16/24 scope global enp8s0
       valid_lft forever preferred_lft forever
    inet6 fd89:14d0:7cce:0:e9d:92ff:fe79:9a2/64 scope global dynamic mngtmpaddr
       valid_lft forever preferred_lft forever
    inet6 fe80::e9d:92ff:fe79:9a2/64 scope link
       valid_lft forever preferred_lft forever
47: tap101i0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master fwbr101i0 state UNKNOWN group default qlen 1000
    link/ether 56:3a:af:f3:38:1f brd ff:ff:ff:ff:ff:ff
48: fwbr101i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 0a:a0:6a:73:df:c3 brd ff:ff:ff:ff:ff:ff
49: fwpr101p0@fwln101i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 0e:7a:02:60:57:5b brd ff:ff:ff:ff:ff:ff
    inet6 fe80::c7a:2ff:fe60:575b/64 scope link
       valid_lft forever preferred_lft forever
50: fwln101i0@fwpr101p0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr101i0 state UP group default qlen 1000
    link/ether ea:4d:24:aa:23:64 brd ff:ff:ff:ff:ff:ff
56: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 06:44:67:be:8a:16 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.1/24 scope global vmbr0
       valid_lft forever preferred_lft forever
    inet6 fe80::444:67ff:febe:8a16/64 scope link
       valid_lft forever preferred_lft forever
57: tap100i0: <BROADCAST,MULTICAST,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master fwbr100i0 state UNKNOWN group default qlen 1000
    link/ether 82:fd:23:01:bd:d9 brd ff:ff:ff:ff:ff:ff
58: fwbr100i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether d6:d7:13:b9:02:44 brd ff:ff:ff:ff:ff:ff
59: fwpr100p0@fwln100i0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master vmbr0 state UP group default qlen 1000
    link/ether fe:47:d8:d4:de:a2 brd ff:ff:ff:ff:ff:ff
60: fwln100i0@fwpr100p0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master fwbr100i0 state UP group default qlen 1000
    link/ether 96:2d:25:a5:61:34 brd ff:ff:ff:ff:ff:ff

and here is my ubuntu 22.04 vm /etc/netplan/00-installer-config.yml file

and here is the list of interfaces, most of which I assume are docker


I am relatively new to networking and vms in general and it has been working fine till I tried to install and nvme ssd and I had to mess around with the files again.

any other information you need just let me know, and thanks in advance!

 

[vesalius]

Try

auto lo
iface lo inet loopback

auto enp8s0
iface enp8s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.1.1/24
        gateway 192.168.1.2
        bridge-ports enp8s0
        bridge-stp off
        bridge-fd 0

Then reboot or do a ifreload -a. You probably should update your proxmox to 6.4, then to the latest 7.3. Although you may be referring to a 6.0.15-edge kernel and not proxmox 6 . What does the command pveversion -v return?

 

[TeenagedLime3]

I changed the /etc/network/interfaces file, did ifreload -a and now I am unable to access proxmox using the webui. Here is the ip a command and pveversion -v command

 

[B.Otto]

What address did you input into your browser? Maybe you have used the 192.168.1.16 address? With the configuration as above you should be able to connect through https://192.168.1.1:8006/

 

[TeenagedLime3]

nope i cannot connnect to https://192.168.1.1:8006/. That ip is already being used anyway for my router ip (https://192.168.1.1), as well as https://192.168.1.2.

 

[B.Otto]

nope i cannot connnect to https://192.168.1.1:8006/. That ip is already being used anyway for my router ip (https://192.168.1.1), as well as https://192.168.1.2.

Well then your original configuration was wrong from the start, which led vesalius to recommend you a wrong interfaces file. There should never be two of the same IP addresses in the same subnet, and both your router and the vmbr0 bridge seem to hold the 192.168.1.1 address. I suppose you added the 192.168.1.2 because of inconsistencies?

If we assume that you want to assign the 16 to your Proxmox host, and that your Proxmox should use the 192.168.1.2 as gateway, edit the interfaces-file like this and do another interface reload:

auto lo
iface lo inet loopback

auto enp8s0
iface enp8s0 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.1.16/24
        gateway 192.168.1.2
        bridge-ports enp8s0
        bridge-stp off
        bridge-fd 0

 

[TeenagedLime3]

My current setup uses 2 routers, one acting i suppose as a bridge. The bridge router is connected into the main router that is connected to the outside. the bridge router is using 192.168.1.2 and the other router is using 192.168.1.1. The bridge router is there to route all traffic through a vpn.
I'll try the above interface file.

 

[vesalius]

Agree @B.Otto,

@TeenagedLime3 what is the output of cat /etc/hosts? This is the primary location the proxmox host expects to get WebGui traffic. Also, do you want proxmox always to use the VPN (change to gateway 192.168.1.2 under vmbr0) or not (change to gateway 192.168.1.1 under vmbr0)?

As to the out of pveversion -v. You are running proxmox 7.3. At some point you want to get off the edge kernel, not sure how or why you have that kernel at this point, and at least move to the linux 6 no-subscription repository kernel. see the first post under https://forum.proxmox.com/threads/opt-in-linux-6-1-kernel-for-proxmox-ve-7-x-available.119483/. I would suggest removing the test repository from your repository list unless you have some very specific reason to utilize it.

 

[TeenagedLime3]

@B.Otto I changed the interfaces file and rebooted the machine, however I can still not access the webui. It also seems the server cannot access the internet as doing "ping google.com" results in the "temporary failure in name resolution" error.

@vesalius

 

[TeenagedLime3]

actually it seems i didnt change the bridge-ports line interface name to be the same as my other interface. It was eth0 rather than enp8s0
im rebooting it now

 

[TeenagedLime3]

i can now access the web ui. I am just seeing now if my vms can be accessed from the network

 

[TeenagedLime3]

it seems my ubuntu vm cannot access the internet still. Here is the netplan config file

 

[TeenagedLime3]

Agree @B.Otto,

@TeenagedLime3 what is the output of cat /etc/hosts? This is the primary location the proxmox host expects to get WebGui traffic. Also, do you want proxmox always to use the VPN (change to gateway 192.168.1.2 under vmbr0) or not (change to gateway 192.168.1.1 under vmbr0)?

As to the out of pveversion -v. You are running proxmox 7.3. At some point you want to get off the edge kernel, not sure how or why you have that kernel at this point, and at least move to the linux 6 no-subscription repository kernel. see the first post under https://forum.proxmox.com/threads/opt-in-linux-6-1-kernel-for-proxmox-ve-7-x-available.119483/. I would suggest removing the test repository from your repository list unless you have some very specific reason to utilize it.

I want all the vms to use the vpn and i dont mind if proxmox does too. I'll go and change back to the non edge repository now.

 

[vesalius]

What network device (listed under Datacenter/ubuntu vm/hardware in the webgui) does the Ubuntu VM use?

Is either or both of your routers (192.168.1.1 or .2) doing DHCP?

 

[TeenagedLime3]

This is the network device on the ubuntu vm

I think both of the routers are doing DHCP for all my wireless devices. I thought if i set it as static in the settings of the device that would be all I would need to. Do I need to set it as static on the router webui too?

 

[TeenagedLime3]

this might be helpful, although idk how to see the list of adapaters (like using ip a) in a compressed version since there are so many devices... I tried using ip link show but I dont think it shows the ipv4 addresses

 

[vesalius]

So if both of the cascaded routers are doing DHCP on the same 192.168.1.0/24 subnet and likely handing out differing DNS/gateways to DHCP clients on your local network, you will inevitably end up with issues. One or both of them may have already handed out 192.168.1.16 or .64 to another DHCP client. Turn DHCP off on at least one (likely easiest to turn it off on 192.168.1.1, since you want .2 to be the vpn gateway). Then best practice is to also reserve the ip (via dhcp reservation and/or a static address) on the router even though your Proxmox and Ubuntu clients are staically assigning themselves that IP.

 

[TeenagedLime3]

since the router not running the vpn is shared I am not allowed to tamper with that. I disabled DHCP on the openwrt vpn router, however it is running through a network switch so i dont know how to reserve ips or change ips on the router. Should I also change the subnet for the vpn router to 192.168.2.0/24?