Hey all, please be patient: I'm an absolute noob, I don't know what I'm doing 
Since yesterday, the download speed of my Proxmox VE 8.4.18 node ('cause I still have 900 Mb/s on my other equipments, including on the switch where the node is plugged in) has brutally dropped from 900 Mb/s to...under 10.
This is my Home Assistant History (one of the two VMs of the node) showing it's a fairly recent issue:
ping and upload speed (it's capped at only 60 Mb/s, though) are unaffected.
Running a speed test on the other VM confirms the internet bandwidth issue:
I didn't test the node itself with a speedtest client but the download speed during an apt install are very bad as well
ethtools looks ok to me:
iperf from the node to a VM is excellent:
iperf from the node to my desktop (upstairs, using Wifi) is pretty good too (500 Mb/s).
It started yesterday but I don't think (I'm sometimes wary of my memory) I've done anything to the Proxmox. The logs in /var/log/apt/ show some upgrade activity on 2026-03-26 and 2026-04-11 (so, today but not yesterday).
What I've tried: I saw there had been issues between Realtek RTL8111 and r8169 and blindly rushed to install the r8168 that seems to solve the problems for some people. It was a mess: r8168, along with dkms and pve-headers had not installed properly and I rebooted the node in that state. Anyway, I fixed that, my node is back on r8169 and connected but the download problem persists.
What can I do?
(Keep in mind I'm pretty useless)
Since yesterday, the download speed of my Proxmox VE 8.4.18 node ('cause I still have 900 Mb/s on my other equipments, including on the switch where the node is plugged in) has brutally dropped from 900 Mb/s to...under 10.
This is my Home Assistant History (one of the two VMs of the node) showing it's a fairly recent issue:
ping and upload speed (it's capped at only 60 Mb/s, though) are unaffected.
Running a speed test on the other VM confirms the internet bandwidth issue:
I didn't test the node itself with a speedtest client but the download speed during an apt install are very bad as well
ethtools looks ok to me:
Code:
root@proxmox:/var/log/apt# ethtool enp1s0
Settings for enp1s0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Link partner advertised pause frame use: Symmetric Receive-only
Link partner advertised auto-negotiation: Yes
Link partner advertised FEC modes: Not reported
Speed: 1000Mb/s
Duplex: Full
Auto-negotiation: on
master-slave cfg: preferred slave
master-slave status: slave
Port: Twisted Pair
PHYAD: 0
Transceiver: external
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: d
Link detected: yesiperf from the node to a VM is excellent:
Code:
root@proxmox:~# iperf3 -c 192.168.0.46
Connecting to host 192.168.0.46, port 5201
[ 5] local 192.168.0.42 port 41978 connected to 192.168.0.46 port 5201
[ ID] Interval Transfer Bitrate Retr Cwnd
[ 5] 0.00-1.00 sec 1.94 GBytes 16.6 Gbits/sec 0 1.72 MBytes
[ 5] 1.00-2.00 sec 1.93 GBytes 16.5 Gbits/sec 0 1.72 MBytes
[ 5] 2.00-3.00 sec 1.93 GBytes 16.5 Gbits/sec 0 1.72 MBytes
[ 5] 3.00-4.00 sec 1.91 GBytes 16.4 Gbits/sec 0 2.03 MBytes
[ 5] 4.00-5.00 sec 2.34 GBytes 20.1 Gbits/sec 0 3.09 MBytes
[ 5] 5.00-6.00 sec 2.61 GBytes 22.4 Gbits/sec 0 3.09 MBytes
[ 5] 6.00-7.00 sec 2.48 GBytes 21.3 Gbits/sec 0 3.09 MBytes
[ 5] 7.00-8.00 sec 2.76 GBytes 23.7 Gbits/sec 86 3.09 MBytes
[ 5] 8.00-9.00 sec 2.57 GBytes 22.1 Gbits/sec 0 3.09 MBytes
[ 5] 9.00-10.00 sec 2.26 GBytes 19.4 Gbits/sec 0 3.09 MBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.00 sec 22.7 GBytes 19.5 Gbits/sec 86 sender
[ 5] 0.00-10.00 sec 22.7 GBytes 19.5 Gbits/sec receiver
iperf Done.iperf from the node to my desktop (upstairs, using Wifi) is pretty good too (500 Mb/s).
It started yesterday but I don't think (I'm sometimes wary of my memory) I've done anything to the Proxmox. The logs in /var/log/apt/ show some upgrade activity on 2026-03-26 and 2026-04-11 (so, today but not yesterday).
What I've tried: I saw there had been issues between Realtek RTL8111 and r8169 and blindly rushed to install the r8168 that seems to solve the problems for some people. It was a mess: r8168, along with dkms and pve-headers had not installed properly and I rebooted the node in that state. Anyway, I fixed that, my node is back on r8169 and connected but the download problem persists.
What can I do?
(Keep in mind I'm pretty useless)
Last edited: