修改Linux网卡连接速度

   发现内网一台Linux服务器向上传输文件时候速度很慢，只有1mb每秒，怀疑网卡运行模式不对，

   使用如下命令查看当前网卡运行模式

ethtool eth0

   得到信息

Settings for eth0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Speed: 10Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 0
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: Unknown
        Supports Wake-on: g
        Wake-on: d
        Current message level: 0x00000000 (0)

        Link detected: yes

   发现网卡是运行在低速的10mb模式下，使用如下命令调整网卡模式未100mb全双工

ethtool -s eth0 speed 100 duplex fullethtool -s eth0 speed 100 duplex full

   再次查看网卡得到信息如下

Settings for eth0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Advertised link modes:  100baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Speed: 100Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 0
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: Unknown
        Supports Wake-on: g
        Wake-on: d
        Current message level: 0x00000000 (0)

        Link detected: yes

   测试文件传输，达到每秒10mb，速度正常