Slow network on Proxmox Host - rtl8125

[lolipop2010]

Hey there.
I'm using proxmox for a few weeks now and today I saw that I only get around 100mbit from my 1gbit network.

The fault HAS to be on the machine since if I use the same cable on another machine I get the full 1gbit.
lspci outputs this: Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller (rev 05)
What I also noticed is that when I start my first VM it drops down to 15mbit but this seems to be a separate issue to me.

What I tried:
- forcing the 1000 via ethtool -s eno1 autoneg on speed 1000 duplex full
This sadly didn't change anything.
- opt-in into newest kernel version with headers.
- r8125 driver from awesometic
This one didnt load somehow. Followed the how to but after blacklisting r8169 I lose all networking.

I hope you can help me.

Kind regards.

 

[RajatSharma]

Hi,
Check the network logs of the VM and of the Proxmox Host try tracing if any service is overwhelming the network.

Have you tried to re-install the drivers from scratch on the host ( DO NOT USE SSH,USE ONLY DIRECT CONNECTION TO MACHINE ).

Check the firewall of the host, Any negotiation settings which might be hindering the network.

Regards.

 

[lolipop2010]

I have the problems with all VM's turned off, so the VM's aint the problem.
Which drivers should I reinstall? The official one from realtek or the proxmox ones?

 

[RajatSharma]

I have the problems with all VM's turned off, so the VM's aint the problem.
Which drivers should I reinstall? The official one from realtek or the proxmox ones?

Try with proxmox drivers and if there's no luck go ahead and do the same with realtek

 

[lolipop2010]

Mhhm. In the meantime I ran a lperf from proxmox host as server and my local windows machine as client
Full 1gbit gets pushed through.

 

[lolipop2010]

Try with proxmox drivers and if there's no luck go ahead and do the same with realtek

Will try that.

 

[lolipop2010]

Mhm. Reinstalling the drivers didnt change anything.

 

[zzz09700]

Full 1gbit gets pushed through.

Then how did you notice you only get 100MBit from your 1GB NIC?
If you can get full 1GB through iperf then everything works as they should, just RTL NIC are not up for the task of virtualization. The bridging and stuff that virtualization depends on might put too much burden to the lousy NIC/crappy driver from RTL

Just noticed RTL8125 is a 2.5GB NIC so there could be compatibility problems if you are using Intel/Broadcom NICs on your local Windows machine.

From my past experience RTL can start a *** show if put in the same subnet with Broadcom NICs and switches from certain brands. Our solution back then was going all in with Intel. Even put in some old Intel 82599 that was scrapped from decommsioned servers in the process, but those worked like a charm.