Linux - The ifconfig command

10.2.3.2. The ifconfig command

While ip is the most novel way to configure a Linux system, ifconfig is still very popular. Use it without option for displaying network interface information:

els@asus:~$ /sbin/ifconfig
eth0      Link encap:Ethernet  HWaddr 00:50:70:31:2C:14
          inet addr:60.138.67.31  Bcast:66.255.255.255  Mask:255.255.255.192
          inet6 addr: fe80::250:70ff:fe31:2c14/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:31977764 errors:0 dropped:0 overruns:0 frame:0
          TX packets:51896866 errors:0 dropped:0 overruns:0 carrier:0
          collisions:802207 txqueuelen:1000
          RX bytes:2806974916 (2.6 GiB)  TX bytes:2874632613 (2.6 GiB)
          Interrupt:11 Base address:0xec00
                                                                                lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:765762 errors:0 dropped:0 overruns:0 frame:0
          TX packets:765762 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:624214573 (595.2 MiB)  TX bytes:624214573 (595.2 MiB)

Here, too, we note the most important aspects of the interface configuration:

The IP address is marked with "inet addr".
The hardware address follows the "HWaddr" tag.

Both ifconfig and ip display more detailed configuration information and a number of statistics about each interface and, maybe most important, whether it is "UP" and "RUNNING".