Use the Ethtool tool to see if the NIC is working

Description:
Ethtool is a command for querying and setting network card parameters.
Summary:
ethtool ethx      //Query EthX network port basic Settings
ethtool–h     & nbsp;  //Display ethtool command help
Ethtool–i ethx   //query EthX port information  
Ethtool–d EthX    /Query EthX network Port registration information
Ethtool–r ethx   //reset EthX port to adaptive mode
Ethtool–s ethx   //Query EthX Network Port Receive package statistics
Ethtool–s EthX [Speed 10|100|1000]\         //set port rate 10/100/1000m
[Duplex half|full]\           //Set the network port half/full Duplex
[Autoneg on|off]\            //Setting the network port is self-negotiating
[port tp|aui|bnc|mii]\         //Setting the port type
[Phyad n]\                 
[XCVR internal|exteral ]\
[Wol p|u|m|b|a|g|s|d ...] \
[Sopass xx:yy:zz:aa:bb:cc]\
[msglvl n]   

Example:

[[Email protected] ~]# Ethtool eth0settings foreth0:supported ports: [TP] supported link Modes:1000baset/Full 10000baseT/Full supported pause frame use:no Supports Auto-negotiation:no advertised Link Modes:not reported advertised pause frame use:no advertised Auto-Negotiation:no SPEED:10000MB/s Duplex:full port:twisted Pair Phyad:0Transceiver:InternalAuto-Negotiation:off MDI-X:unknown Supports Wake-On:uag Wake-on:d Link detected:yes[[email protected]~]# Ethtool eth1settings foreth1:supported ports: [TP] supported link Modes:1000baset/Full 10000baseT/Full supported pause frame use:no Supports Auto-negotiation:no advertised Link Modes:not reported advertised pause frame use:no advertised Auto-Negotiation:no Speed:unknown!Duplex:unknown! (255) port:twisted Pair Phyad:0Transceiver:InternalAuto-Negotiation:off MDI-X:unknown Supports Wake-On:uag Wake-on:d Link Detected:no

Use the Ethtool tool to see if the NIC is working