====== Ethtool ======

**General Information**

Display and set ethernet interface settings. 

**Checklist**
  * Distro(s): Enterprise Linux

----

====== Display Settings ======

To display the settings of a network interface:
<code bash>
ethtool eth0
</code>

----

====== Set Speed/Duplex ======

Set eth0 to 100 Mbps and full duplex
<code bash>
ethtool -s eth0 speed 100 duplex full autoneg off
</code>

===== Permanent Settings =====

To make speed settings permanent, edit the network script at /etc/sysconfig/network-scripts/ifcfg-eth0 and append:

For 100 Mbps
<code bash>
ETHTOOL_OPTS="speed 100 duplex full autoneg off"
</code>
\\

For 1000 Mbps (1 Gbps)
<code bash>
ETHTOOL_OPTS="speed 1000 duplex full autoneg on"
</code>
  * **Note:** Gigabit requires autoneg to be on, even though you are manually specifying speed and duplex.

----