The ifconfig command can tell you a lot about your Unix server’s connection to your network and the role it’s playing in both generating and receiving network traffic.
The newer ip command does much the same thing, but you won’t find it on all varieties of Unix. Both commands will display a lot of settings and numbers associated with your network connection. Let’s look into what all those numbers and settings mean.
For starters, ifconfig stands for “interface configuration”. The command provides options for viewing as well as changing your network settings.
By itself (no options), the ifconfig command shows active network interfaces (you may have others). This is generally the primary network interface – usually eth0 – and the loopback address as shown in the example below.
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