I have deployed an N150 based Proxmox 9.1.6. home server. To speed up my NAS VM I bought a UGREEN 2.5G USB ethernet adapter. However it only connects at 1G. To my surprise both the interface and the switch show 2.5G capabilities, but that speed is not advertised.
This is from the Proxmox shell:
# ip link
[..]
14: enx6c1ff7044e92: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
link/ether 6c:1f:f7:04:4e:92 brd ff:ff:ff:ff:ff:ff
# ethtool enx6c1ff7044e92
Settings for enx6c1ff7044e92:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
2500baseT/Full
Supported pause frame use: No
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: No
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
2500baseT/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
Port: MII
PHYAD: 32
Transceiver: internal
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00007fff (32767)
drv probe link timer ifdown ifup rx_err tx_err tx_queued intr tx_done rx_status pktdata hw wol
Link detected: yes
ethtool -s enx6c1ff7044e92 speed 2500 duplex full autoneg off
Does not help either (link settings update failed)
The same adapter connects at 2.5G on a Windows 11 laptop.
