一、命令描述：

ethtool 是用于查询及设置网卡参数的命令。

ethtool eth0      		 //查询eth网口基本设置
ethtool –h       		 //显示ethtool的命令帮助(help)
ethtool –i eth0    		 //查询eth0网口的相关信息 
ethtool –d eth0    	     //查询eth0网口注册性信息
ethtool –r eth0    		 //重置eth0网口到自适应模式
ethtool –S eth0   	     //查询eth0网口收发包统计
ethtool –s eth0 [speed 10|100|1000] [duplex half|full] [autoneg on|off] //设置网口速率10/100/1000M、网口半/全双工、网口是否自协商
ethtool -E eth0 magic 0x10798086 offset 0x10 value 0x1A     //修改网卡EEPROM内容（0x1079 网卡device id , 0x8086网卡verdor id  ）
ethtool -e eth0       //dump网卡EEPROM内容

二、使用举例：
1） ethtool ens33


2） ethtool -i ens33

3） ethtool -S ens33

4）ethtool -a ens33 查找流控开关

5）ethtool -t ens33

[root]# ethtool -t ens33
The test result is PASS
The test extra info:
Register test (offline) 0
Eeprom test (offline) 0
Interrupt test (offline) 0
Loopback test (offline) 0
Link test (on/offline) 0

5）ethtool -h
关于更大用法，可以查询

ethtool -h
ethtool version 5.4
Usage:
        ethtool DEVNAME	Display standard information about device
        ethtool -s|--change DEVNAME	Change generic options
		[ speed %d ]
		[ duplex half|full ]
		[ port tp|aui|bnc|mii|fibre ]
		[ mdix auto|on|off ]
		[ autoneg on|off ]
		[ advertise %x ]
		[ phyad %d ]
		[ xcvr internal|external ]
		[ wol p|u|m|b|a|g|s|f|d... ]
		[ sopass %x:%x:%x:%x:%x:%x ]
		[ msglvl %d | msglvl type on|off ... ]
        ethtool -a|--show-pause DEVNAME	Show pause options
        ethtool -A|--pause DEVNAME	Set pause options
		[ autoneg on|off ]
		[ rx on|off ]
		[ tx on|off ]
        ethtool -c|--show-coalesce DEVNAME	Show coalesce options
        ethtool -C|--coalesce DEVNAME	Set coalesce options
		[adaptive-rx on|off]
		[adaptive-tx on|off]
		[rx-usecs N]
		[rx-frames N]
		[rx-usecs-irq N]
		[rx-frames-irq N]
		[tx-usecs N]
		[tx-frames N]
		[tx-usecs-irq N]
		[tx-frames-irq N]
		[stats-block-usecs N]
		[pkt-rate-low N]
		[rx-usecs-low N]
		[rx-frames-low N]
		[tx-usecs-low N]
		[tx-frames-low N]
		[pkt-rate-high N]
		[rx-usecs-high N]
		[rx-frames-high N]
		[tx-usecs-high N]
		[tx-frames-high N]
		[sample-interval N]
        ethtool -g|--show-ring DEVNAME	Query RX/TX ring parameters
        ethtool -G|--set-ring DEVNAME	Set RX/TX ring parameters
		[ rx N ]
		[ rx-mini N ]
		[ rx-jumbo N ]
		[ tx N ]
        ethtool -k|--show-features|--show-offload DEVNAME	Get state of protocol offload and other features
        ethtool -K|--features|--offload DEVNAME	Set protocol offload and other features
		FEATURE on|off ...
        ethtool -i|--driver DEVNAME	Show driver information
        ethtool -d|--register-dump DEVNAME	Do a register dump
		[ raw on|off ]
		[ file FILENAME ]
        ethtool -e|--eeprom-dump DEVNAME	Do a EEPROM dump
		[ raw on|off ]
		[ offset N ]
		[ length N ]
        ethtool -E|--change-eeprom DEVNAME	Change bytes in device EEPROM
		[ magic N ]
		[ offset N ]
		[ length N ]
		[ value N ]