[SOLVED] virtual machine connectivity issue on Proxmox

Spart

New Member
May 2, 2024
8
0
1
I'm having a problem with Proxmox, more specifically with my Debian virtual machines not having access to the Internet. I verified that Proxmox can ping to 8.8.8.8 as well as the gateway, and everything seems to be working fine there. However, when I launch a virtual machine, it cannot connect to the Internet.

Here is some additional information:

-I use Proxmox version 8.2.2

cat /etc/resolv.conf
search home
nameserver 192.168.1.1

root@pve:~# cat /etc/network/interfaces
auto lo
iface lo inet loopback

auto enp0s3
iface enp0s3 inet manual

auto vmbr0
iface vmbr0 inet static
address 192.168.1.61/24
gateway 192.168.1.1
bridge-ports enp0s3
bridge-stp off
bridge-fd 0

source /etc/network/interfaces.d/*

I would also like to point out that I am new to using Proxmox, so any additional explanations or instructions would be greatly appreciated.
Thank you for your understanding and help!

Thank you in advance for your assistance!
 

Attachments

  • Debian_Hardware.png
    Debian_Hardware.png
    26.4 KB · Views: 19
  • Debian_Option.png
    Debian_Option.png
    30.8 KB · Views: 20
  • ip.png
    ip.png
    44.3 KB · Views: 14
Last edited:
If you want to be able to use IPv4 (and ping 8.8.8.8 is IPv4) you need to give your guest an IPv4 address. The third screenshot shows only a IPv6 one.

Something like "ip addr add 192.168.1.123/24 dev ens18 && ip route add default via 192.168.1.1" may be sufficient for a non-persistent test. (From my mind, not verified.)
 
I thank you in advance for your response, I made the modifications given but the problem persistsip a .png
 
Okay, next round...
  • you set 192.168.1.123 as the local address - fine!
  • you can ping .1.61 - fine! Physical connectivity is present!
  • you can NOT ping .1.1 - BAD!
So... Is 192.168.1.1 the "exit" out of this network? It should answer to "ping"! (Or it is something esoteric and blocks icmp echo requests. What kind of device is it?)

You need to find out more details about your network. Only you can do that.

What kind of router is it? Does it have a web frontend? Does it have a status page? Does is show the network configuration it serves?

On the pingable system .1.61: what is this? Also Linux? Can it ping .1.1? Can it access the internet? How is routing configured there? What gives "ip route" on that system?
 
-192.168.1.1 is the IP address of the 'Livebox Orange Fibre,' which acts as the main router in the network and has a web interface.
-192.168.1.61is the IP address of the Proxmox control panel interface, which is virtualized within VirtualBox. It can successfully ping both 192.168.1.1 and 8.8.8.8.


Here is a screenshot giving more detail:
ProxMox Interface
Proxmox 192.168.1.1.png
NetWork interface Option.pngDebian.png
 
to confirm within guest network conf error, boot from Live Debian or Ubuntu
 
  • Like
Reactions: UdoB
After following your advice, I installed Ubuntu "debian-live-12.5.0-amd64-cinnamon". I manually made some changes through the network interface, and I've made progress! I can now ping my gateway, but I still lack the ability to ping 8.8.8.8. Here's a screenshot where I made the modification:
 

Attachments

  • ping 192.168.1.1.png
    ping 192.168.1.1.png
    196.6 KB · Views: 5
I tried to do the configuration manually but nothing works, impossible to ping anything. I don't understand except for 192.168.1.61

and I changed 192.168.1.123 to 192.168.1.49 which is also free
 

Attachments

  • Picture1.png
    Picture1.png
    15.3 KB · Views: 6
  • picture2.png
    picture2.png
    43 KB · Views: 5
  • picture3.png
    picture3.png
    168.5 KB · Views: 6
  • ping 192.168.1.1.png
    ping 192.168.1.1.png
    117.8 KB · Views: 6
Last edited:
I found the problem, wow! I searched everywhere, and it just shows that perseverance always pays off! I tried disabling firewalls everywhere, but it didn't change anything. The issue was with VirtualBox. In the tutorials I followed to install VirtualBox, it wasn't mentioned at all that you needed to have multiple network interfaces, such as adapter 1 needing to be set to bridged mode and in the advanced network settings, to paravirtualization (virtio-net). Then, you need an adapter 2 in NAT. In Proxmox, you need to add vmbr0 to the bridge connection. The new interface that was added in my case is enp0s8.

source :

Install and Run Proxmox VE

https://pve.proxmox.com/wiki/Proxmo...n_requires_VirtualBox_NIC_in_promiscuous_mode

Here are some screenshots, as my translation might not be correct.
picture2.pngadd enp0s8 in the bridge port


picture1.pngpicture1.pngpicture1.png
 
Last edited:
The issue was with VirtualBox.
This information was important to write in your first post !

In the tutorials I followed to install VirtualBox, it wasn't mentioned at all that you needed to have multiple network interfaces
It's not needed at all.
Docs says you can use NAT from VirtualBox if you want an isolated network for your main network (like a nested network)
OR
if you want network "Bridged" (=Accès par pont) to your main primary network, you need to switch promiscuous mode ( = Mode Promiscuité ) from Deny (=Refuser) to Accept (= Accepter).
 

About

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!