[CentOS] GRabbing MAC address

On Thu, 28 Feb 2008, Wojtek Pilorz wrote:

> On Thu, Feb 28, 2008 at 08:13:17AM -0600, Les Mikesell wrote:
>> Jerry Geis wrote:
>>> I am trying to grab the mac address for eth0 on centos 5.1 with
>>>
>>> ifconfig | grep eth0 | cut -d ' ' -f 5 and I dont get anything.
>>>
>>> What am I not doing right?
>>>
>>> ifconfig | grep eth0 | cut -d ' ' -f 1 gives me eth0 but anything 
>>> else like -f 2, -f 3 etc I get nothing.
>>
>> If sed had been invented first, we wouldn't need grep.
>>
>> ifconfig |sed -n -e 's/eth0.*\(..:..:..:..:..:..\)/\1/p'

Or awk! :-) And you can ditch ifconfig entirely and use /sbin/ip,
which defaults to a lower-case version of the MAC rather than the
upper-case presentation used by ifconfig:

   ip link show eth0 | awk '/ether/ {print $2}'

I mean, doesn't everyone use lower-case MACs in dhcpd.conf? :-)

-- 
Paul Heinlein <> heinlein at madboa.com <> http://www.madboa.com/