[New Installation] Proxmox 8.0 - Network interfaces down and cannot be brought up

[Jephgag]

Hello,

I installed Proxmox 8.0 on a newly built PC and I cannot ping anything from my proxmox machine. The new machine has a dedicated 4 port Intel Nic (not sure if that makes a difference or not)

When I installed Proxmox, the DHCP server gave the ip 192.168.100.112.

Here is a screenshot of ip a command.



I can see that vmbr0 and enp5s0 are down. I tried to bring them up with ip link set dev <enp5s0/vmbr0> up, but nothing changed.

This is my /etc/network/interfaces file :


And this is the results of systemctl status networking:


I can see here that the networking process has exited. I am not sure if that is normal, but it feels like it should be active (running). I tried deactivating and reactivating the service to no avail. It always exits.

I am not sure where to go from there to debug this issue.

If that makes any difference, here is my setup:

AMD Ryzen 5 5600G 3.9 GHz 6-Core Processor

Gigabyte B450M DS3H WIFI Micro ATX AM4 Motherboard

TEAMGROUP T-Force Vulcan Z 16 GB (2 x 8 GB) DDR4-3200 CL16 Memory

Kingston A400 120 GB 2.5" Solid State Drive

Seagate IronWolf NAS 4 TB 3.5" 5400 RPM Internal Hard Drive

Seagate IronWolf NAS 4 TB 3.5" 5400 RPM Internal Hard Drive

and the Intel NIC Card is I350-T4V2. I tried removing this NIC card and only using the ethernet cable on the mobo, but I still get the same issues. So my guess is that there is an issue with Proxmox installation.

Thank you for your time.

 

[bbgeek17]

What makes you think that enp5s0 is the right interface to use in vmbr? It clearly states that the NIC detected "NO CARRIER", meaning either there is no cable or the other side of the cable is not plugged into anything.
Its unclear what the state of the PC was when you removed one NIC, because you do not post any output from that time.

Please be methodical in your testing/troubleshooting. Note the state at each point. Removing NIC is not enough to make things work, your interface naming could have changed.

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Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[Jephgag]

What makes you think that enp5s0 is the right interface to use in vmbr?

During the proxmox installation, there was an iteration through all the 5 physical ports and only one physical port was connected to the network and was able to get the ip address from the DHCP server.

I was simply stating that removing the 4-port NIC and reinstalling proxmox using only the motherboard ethernet port yielded the same end results. In the end, I need the 4-port NIC and the information presented above is the state I am in right now fresh off the installation process.

I feel that you are unjustly harsh when I feel like I've done my due dilligence in asking my question.

I do not have a deep knowledge of Proxmox and networking overall. I installed proxmox before and never had this issue.

 

[bbgeek17]

During the proxmox installation, there was an iteration through all the 5 physical ports and only one physical port was connected to the network and was able to get the ip address from the DHCP server.

This is new information that you did not provide in the opening. It is important for those who dont have access and history with your system.
Did you record which interface it was? Do you know what changed since that time? Did you bump the cable? Re-arranged PCI slots?

I was simply stating that removing the 4-port NIC and reinstalling proxmox using only the motherboard ethernet port yielded the same end results.

But thats different what you actually stated. There is nothing about removal of NIC coinciding with full re-install in your opening post. Volunteers here only have the data you provide to draw conclusions.

I feel that you are unjustly harsh when I feel like I've done my due dilligence in asking my question.

I've asked you to confirm things that only you would know - are you using correct interface? The interface you are using shows "NO CARRIER". This is a hardware link detection layer. There is nothing you can do in software/configuration to change that.
The solution could be as easy as moving or changing the cable, in which case there is no need to dive into deep network troubleshooting. It could be bad cable, bad NIC, bad port, Kernel incompatibility, PCI conflict, etc.
The first rule of any troubleshooting - look at low hanging fruit. In this case - link detection. Try other ports on your intel NIC.

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Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox