The ip command has a lot to tell you about the configuration and state of your network connections, but what do all those words and numbers mean? Let\u2019s take a deep dive in and see what all the displayed values are trying to tell you.\nWhen you use the ip a (or ip addr) command to get information on all the network interfaces on your system, you're going to see something like this:\n$ ip a\n1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000\n link\/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00\n inet 127.0.0.1\/8 scope host lo\n valid_lft forever preferred_lft forever\n inet6 ::1\/128 scope host\n valid_lft forever preferred_lft forever\n2: enp0s25: mtu 1500 qdisc pfifo_fast state UP group default qlen 1000\n link\/ether 00:1e:4f:c8:43:fc brd ff:ff:ff:ff:ff:ff\n inet 192.168.0.24\/24 brd 192.168.0.255 scope global dynamic enp0s25\n valid_lft 57295sec preferred_lft 57295sec\n inet6 fe80::2c8e:1de0:a862:14fd\/64 scope link\n valid_lft forever preferred_lft forever\n\nThe two interfaces on this system \u2014 the loopback (lo) and network (enp0s25) \u2014 are displayed along with a lot of stats. The "lo" interface is clearly the loopback. We can see the loopback IPv4 address (127.0.0.1) and the loopback IPv6 (::1) in the listing. The normal network interface is more interesting.\n\n\n\n\n\nWhy enp0s25 and not eth0\nIf you're wondering why it's called enp0s25 on this system instead of the likely more familiar eth0, a little explanation is in order.\nThe new naming scheme is referred to as the \u201cPredictable Network Interface\u201d naming. It\u2019s been used on systemd-based Linux systems for some time. The interface name depends on the physical location of the hardware. The "en" simply means "ethernet" just like "eth" does for eth0. The "p" is the bus number of the ethernet card and the "s" is the slot number. So "enp0s25" tells us a lot about the hardware we're working with.\nThe string of settings tell us that ...\nBROADCAST the interface supports broadcasting\nMULTICAST the interface supports multicasting\nUP the network interface is enabled\nLOWER_UP the network cable is plugged in and device connected to network\nmtu 1500 the maximum transfer unit (packet size) is 1,500 bytes\n\nThe other values listed also tell us a lot about the interface, but we need to know what words like "brd" and "qlen" represent. So, here's a translation of the rest of the ip a shown above.\nmtu 1500 maximum transfer unit (packet size)\nqdisc pfifo_fast used for packet queueing\nstate UP network interface is up\ngroup default interface group\nqlen 1000 transmission queue length\nlink\/ether 00:1e:4f:c8:43:fc MAC(hardware) address of the interface\nbrd ff:ff:ff:ff:ff:ff broadcast address\ninet 192.168.0.24\/24 IPv4 address\nbrd 192.168.0.255 broadcast address\nscope global valid everywhere\ndynamic enp0s25 address is dynamically assigned\nvalid_lft 80866sec valid lifetime for IPv4 address\npreferred_lft 80866sec preferred lifetime for IPv4 address\ninet6 fe80::2c8e:1de0:a862:14fd\/64\t\tIPv6 address\nscope link valid only on this device\nvalid_lft forever valid lifetime for IPv6 address\npreferred_lft forever preferred lifetime for IPv6 address\n\nYou might have noticed that some of the information that the ifconfig command provides is not included in the ip a output \u2014 such as the stats on transmitted packets. If you want to see a list of the number of packets transmitted and received along with collisions, you can use this ip command:\n$ ip -s link show enp0s25\n2: enp0s25: mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000\n link\/ether 00:1e:4f:c8:43:fc brd ff:ff:ff:ff:ff:ff\n RX: bytes packets errors dropped overrun mcast\n 224258568 418718 0 0 0 84376\n TX: bytes packets errors dropped carrier collsns\n 6131373 78152 0 0 0 0\n\nAnother ip command provides information on a system's routing table.\n$ ip route show\ndefault via 192.168.0.1 dev enp0s25 proto static metric 100\n169.254.0.0\/16 dev enp0s25 scope link metric 1000\n192.168.0.0\/24 dev enp0s25 proto kernel scope link src 192.168.0.24 metric 100\n\nThe ip command is extremely versatile. You can get a helpful cheat sheet on the ip command and its options from Red Hat.