Hi,

I would like to know how to find out ACTUAL speed of NIC Card.

I have used the command ethtool eth0, it is showing supported modes,

but what is acutal speed ? how to find out?

# ethtool eth0
Settings for eth0:
    Supported ports: [ TP ]
    Supported link modes:   10baseT/Half 10baseT/Full 
                            100baseT/Half 100baseT/Full 
    Supports auto-negotiation: Yes
    Advertised link modes:  10baseT/Half 10baseT/Full 
                            100baseT/Half 100baseT/Full 
                            1000baseT/Full 
    Advertised auto-negotiation: Yes
    Speed: 100Mb/s             <-------------- !

Thanks RudiC,I am confused becuase mii-tool is showing diffrent speed.


output of eth-tool

 ethtool eth1
Settings for eth1:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 1
        Transceiver: internal
        Auto-negotiation: on
        Supports Wake-on: g
        Wake-on: d
        Link detected: yes

mii-tool eth1
eth1: negotiated 100baseTx-FD flow-control, link ok

I don't think gigabit uses mii anymore. That is to say, mii has no way of reporting speeds above 100baseT, a new standard was made.

Many Many Thanks Corona688.