Virtualized OpnSense full download speed but 10% of upload


Dec 7, 2020
So, this is a weird situation.

I have a virtualized OpnSense under Proxmox. In fact they are two acting as HA. Last week I had a hardware failure on the main Proxmox hw and had to change the hardware. I returned the backuped VM on the new HW and it appeared to be fine.

When I checked the upload speed it is not going beyond 20 mbps, it should be 150 mbps. The download speed is fine at 350mbps. It showed me that the speed of the virtual NIC seems to be ok. I have changed the physical switch port, the ethernet cable the USB NIC dongle and the situation is the same.

I entered in Temp Maintenance mode and the secondary OpnSense can upload up to 150 mbps. So, there is no problem at the ISP side.

I've reinstalled OpnSense from the scratch and the situation persists.

I don't know what is going on. How can I solve this problem ?
How does your VM-Config look like? For example: qm config 101 So the hw changed, is it the same hw? Maybe the usb port is different, something changed? Have you checked your bios for some settings that might affect performance of your usb nic dongle?
I have checked the usb config, changed the usb port , changed the cables etc.

My line of thought is, if it can download at 350mbps it shouldn’t be any hw issue nor the cable or port. It kind of proved that it can handle higher speeds.

My thoughts are now with the Realtek drivers. The old hardware came from version 7 of Proxmox. Even though I have upgraded it to latest version, I was wondering if the old driver where there and was being used. There could be a cause.
So, I was able to figure this out. I had to install the r8168-dkms to make it work properly. Looks like the r8169 or something wasn't 100% compatible.

Once I installed it the performance went back to the normal.

Not sure if it will be ever fixed on the newer driver
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