[SOLVED] How can I specifiy a nominal speed of a kvm virtio NIC?

[UdoB]

Good morning,

while expanding monitoring of my PVE systems I am stumbling over a (for me) problematic detail: the reported speed of a virtual NIC is always "10", which means 10 MBit/s. Specifically the host tells me this for any VM:

root@pm1:~# cat /sys/class/net/tap110i0/speed
10

Just for comparision: the hardware NICs shows 1000 MBit/s:

root@pm1:~# cat /sys/class/net/enp3s0f0/speed
1000

This is a virtual NIC using the virtio driver. It is expected to not report the physical speed. I know it is not limiting the actual transfer speed in any way. So there is no problem regarding performance.

Except for monitoring it triggers warnings much too early: saturation of a link in percent is calculated like $actualvalue/$maxvalue*100. So when I transmit 20 MBit/s I get a warning that my network is overloaded because it transmits 200 percent of its capabilities

My question boils down to: how can I specify the nominal speed of a virtio-NIC in a sane way?


While I CAN spedifiy a nominal speed this way:

root@pm1:~# ethtool -s tap110i0 speed 1000
root@pm1:~# cat /sys/class/net/tap110i0/speed
1000

... this is probably not the correct way to do it - and it is not persistent...



Also "man qm" --> "net[n]: [model=]<enum> [,bridge=<bridge>] [,firewall=<1|0>] [,link_down=<1|0>] [,macaddr=<XX:XX:XX:XX:XX:XX>] [,mtu=<integer>] [,queues=<integer>] [,rate=<number>] [,tag=<integer>] [,trunks=<vlanid[;vlanid...]>] [,<model>=<macaddr>]" doesn't help as "rate" is a different thing here.

The configuration of the NIC is simply this:

root@pm1:~# grep net0:  /etc/pve/local/qemu-server/110.conf
net0: virtio=4E:69:F4:3C:C0:97,bridge=vmbr0,firewall=1,tag=814

Any idea and any pointer welcome...

Best regards

---

Edit a few minutes later: @fabian postet a Link in the german forum: https://bugzilla.proxmox.com/show_bug.cgi?id=4220
My Bridge has a physical NIC with 1GBit/s already...
2. Edit: referenced bug reopened

 

[nobody0815]

as described here: https://forum.proxmox.com/threads/l...t-mit-10mbit-s-link-speed.112167/#post-528373
Maybe an Cron helps to set new TAPs to whatever you think:
lshw -class network | grep "ogical name: tap*" |while read line ; do ethtool -s ${line/"logical name: "/""} speed 1000 ; done

 

[UdoB]

Solved by "cron" (see above) and also with another approach in https://forum.proxmox.com/threads/l...rt-mit-10mbit-s-link-speed.112167/post-568146 (German)