指定网卡工作模式使用 ethtool命令，有时候会使用mii-tool ，但是这个命令显示不太准确，1000M的也会显示成100M


ethtool eth0  #产看eth0网卡的信息

[root@localhost ~]# ethtool  eth0

Settings for eth0:

        Supported ports: [ TP MII ]

        Supported link modes:   10baseT/Half 10baseT/Full 

                                100baseT/Half 100baseT/Full 

                                1000baseT/Half 1000baseT/Full 

        Supported pause frame use: No

        Supports auto-negotiation: Yes

        Advertised link modes:  1000baseT/Full 

        Advertised pause frame use: Symmetric Receive-only

        Advertised auto-negotiation: Yes

        Link partner advertised link modes:  10baseT/Half 10baseT/Full 

                                             100baseT/Half 100baseT/Full 

                                             1000baseT/Full 

        Link partner advertised pause frame use: No

        Link partner advertised auto-negotiation: Yes

        Speed: 100Mb/s  #此处为当前的工作模式信息

        Duplex: Full

        Port: MII

        PHYAD: 0

        Transceiver: internal

        Auto-negotiation: on

        Supports Wake-on: pumbg

        Wake-on: g

        Current message level: 0x00000033 (51)

                               drv probe ifdown ifup

        Link detected: yes


更改网卡的工作模式：使用-s 参数

# ethtool -s eth0 autoneg on speed 1000 duplex full



[root@localhost ~]# ethtool  eth0

Settings for eth0:

        Supported ports: [ TP MII ]

        Supported link modes:   10baseT/Half 10baseT/Full 

                                100baseT/Half 100baseT/Full 

                                1000baseT/Half 1000baseT/Full 

        Supported pause frame use: No

        Supports auto-negotiation: Yes

        Advertised link modes:  1000baseT/Full 

        Advertised pause frame use: Symmetric Receive-only

        Advertised auto-negotiation: Yes

        Link partner advertised link modes:  10baseT/Half 10baseT/Full 

                                             100baseT/Half 100baseT/Full 

                                             1000baseT/Full 

        Link partner advertised pause frame use: No

        Link partner advertised auto-negotiation: Yes

        Speed: 1000Mb/s

        Duplex: Full

        Port: MII

        PHYAD: 0

        Transceiver: internal

        Auto-negotiation: on

        Supports Wake-on: pumbg

        Wake-on: g

        Current message level: 0x00000033 (51)

                               drv probe ifdown ifup

        Link detected: yes