New Member
Jan 20, 2021

I am trying to change the port speed of my server port to 100baseT/Full. The port is part of a supermicro motherboard. The port is being used as a Linux bridge.

The ethtool output:
root@pve:~# ethtool eno1
Settings for eno1:
Supported ports: [ TP ]
Supported link modes: 1000baseT/Full
Supported pause frame use: Symmetric
Supports auto-negotiation: Yes
Supported FEC modes: Not reported
Advertised link modes: 1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown
Supports Wake-on: g
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes

root@pve:~# ethtool vmbr0
Settings for vmbr0:
Link detected: yes

I have tried variations of:
ethtool -s eno1 autoneg off speed 100 duplex full

ethtool -s eno1 speed 100 ...etc.

none seem to work.

Correct me if I am wrong please, but vmbr0 would not need to be changed as it inherits from eno1 settings?

I want to reduce to 100 because I am connecting it to an old cisco switch 2960 and the port will not come up with it since the supermicro server seems to have its port speed hardcoded as I see no other supported link modes in the ethtool output of eno1.

Any ideas if this port speed change is even possible?

Thank you for any guidance.


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