[SOLVED] Loss of network when install in TP-Link TX201

Jungle153

New Member
Feb 19, 2025
10
0
1
Good evening,

I am running into some issues when trying to add a new NIC to an existing Proxmox install.

My current network setup is via an onboard Realtek 1gb ethernet controller on a Gigabyte motherboard (all consumer grade equipment, in a homelab setup). I am trying to add a TP-Link TX201 2.5gb PCIe NIC.

Symptom of issue: When I add the card and power up the server the pve boots up (I know this as I have attached a monitor and keyboard and can log in to the CLI with my normal credentials). However there is no network connectivity via either of the NIC's. When booting the CLI login screen the advertised GUI weblink defaults to the IP generated when Proxmox was installed (before I gave it a new IP on a different subnet (server)). When added back to the original subnet (home office) again no network connectivity on either NIC.

Other things I have tried:
1. Disabling onboard NIC to rule out a hardware conflict - same issue
2. Installing new instance of Proxmox on a spare SSD with both NIC's active - All works as expected with both network interfaces visible (This is a possible solution, however I rather not try and migrate all lxc's, vm's and zfs pools to a new install).

When logged in via CLI (without connectivity) and viewing the /etc/network/interfaces file, the config reflects the setup for normal operation on the server subnet via the onboard NIC. When TX201 card installed lspci shows both network interfaces.

What I think is happening: when I install the new NIC and boot up Proxmox is giving the onboard NIC a new interface name (currently enp4s0) as well as issuing a name for the new NIC. This is resulting in a mismatch with the config in /etc/network/interfaces and loss of network connectivity.

What I don't know:
1. How to identify enp name given to both NIC's by proxmox from CLI in order to try and edit /etc/network/interfaces and change interface name.
2. How to force Proxmox to keep enp name for onboard NIC so that I can set up the new one via the GUI.
3. If the above are viable solutions to the problem.

If anyone has had a similar experience and could help I would be very grateful, or if anyone can give guidance on how to solve the problem either via CLI or re-establishing GUI access and I can go from there.

Please let me know if you need any further information to help problem solve, any configs and messages will have to be added as a jpeg.

Many thanks
Jungle
 
Thanks for the quick response. I forgot to mention that in the OP. There is no connectivity at all. Proxmox is not getting an IP, I can see that in the DHCP Leases page on pfSense. Also there is no outgoing network traffic (tries pining local IP's and google)
 
Thank you for your response. Proxmox is configured on my network and has been working perfectly with the onboard 1gb NIC. The problem only occurs when I add the new 2.5gb NIC. It takes out all conectivity, when the card is removed conectivity returns to normal.

The static mappings show up in pfSense DHCP leases.
 
How to force Proxmox to keep enp name for onboard NIC so that I can set up the new one via the GUI
Proxmox added a NIC name pinning tool in v8 that links the names nic0/1/2/3/etc. to the MAC address of the card, so the names don't change if you add cards or upgrade kernels. It will change once but then should never change again.

https://pve.proxmox.com/wiki/Network_Configuration#:~:text=Overriding Network Device Names

basics:
run: pve-network-interface-pinning generate
do NOT apply changes, you must restart Proxmox
 
  • Like
Reactions: Jungle153
Proxmox added a NIC name pinning tool in v8 that links the names nic0/1/2/3/etc. to the MAC address of the card, so the names don't change if you add cards or upgrade kernels. It will change once but then should never change again.

https://pve.proxmox.com/wiki/Network_Configuration#:~:text=Overriding Network Device Names

basics:
run: pve-network-interface-pinning generate
do NOT apply changes, you must restart Proxmox
Thank you, that looks like a possible solution. I'll give it a try in the morning. Fingers crossed it does the job.
 
I would think you'd need to run it a second time to pin the new NIC, after it's installed? I haven't gotten that far, haven't actually added any NICs to Proxmox... There are command line options to do it only on certain NICs, I see.
 
  • Like
Reactions: Jungle153
Your network Interface names will be change, when you at another PCI Express device. you must check, if you have the right driver for your TX 201. Please see: https://www.tp-link.com/us/support/faq/3435/
Hi, thank you. I suspected this to be the case as mentioned in my OP. What I was hoping for is a way to identify the new names from the CLI so that I can update the interfaces config.

As I understand it the driver for the Realtek chip on the TX201 is now in the kernel.

Once I can find the new enp names and the config is updated I can then access the GUI.
 
I would think you'd need to run it a second time to pin the new NIC, after it's installed? I haven't gotten that far, haven't actually added any NICs to Proxmox... There are command line options to do it only on certain NICs, I see.
That's worth knowing, although I've never had any problems with kernel updates killing network connectivity. Been on proxmox since v7.something. That said I've only ever has the one NIC so may well have auto updated everything.
 
Run ip a in CLI
Apologies, I misunderstood your answer earlier. With you now. I didn't consider that IP a doesn't just give allocated IP addresses. That's all I've used it for in the past.

Still on a steep learning curve with Linux CLI use.

Thank you, I'll give it a try in the morning.
 
@news and @SteveITS thank you both for your help. I've got the NIC installed and working. I tried editing the interfaces config with new enp name, this didn't work (I suspect I need to change some other config to activate the nic).

Final solution was to pin the nic ID, add the card and reboot. I could then complete the setup in the GUI and change vmbr0 to default to the new nic (also pinned).

Thank you again. And if you celebrate Merry Christmas.