Output only MAC address on Ubuntu

In Ubuntu, with command ifconfig -a, I obtain all the information about my ethernet/wifi interfaces.

But I need to obtain as output only the MAC address, like:

ab:cd:ef:12:34:56
57:89:12:34:ac:23
12:34:56:ab:cd:ef

How can I obtain this?

Solution 1:

You can access the address file for each device on the /sys virtual filesystem. The MAC address should be in /sys/class/net/<device-name>/address:

$ cat /sys/class/net/enp1s0/address
34:17:eb:5d:88:7c

For all devices:

$ cat /sys/class/net/*/address
34:17:eb:5d:88:7c
00:00:00:00:00:00
64:5a:04:69:50:45

Solution 2:

The easiest way would be to use grep with PCRE:

$ ifconfig -a | grep -Po 'HWaddr \K.*$'
74:d4:35:84:34:13  

• grep -P will enable us to use perl compatible Regex

• grep -o will only take the matched portion of the line

• We have matched HWaddr before our desired match (MAC addresses) and then discard HWaddr by \K to print only the MAC addresses.

@Helio has mentioned an important point, this is highly dependent on your language i.e. locale settings. To overcome that you can use the C locale (uses ASCII character set) for this command only:

$ LANG=C ifconfig -a | grep -Po 'HWaddr \K.*$'
74:d4:35:84:34:13