whatis ip-address
IP Address
Also known as: IPv4, IPv6, CIDR
The numeric address identifying a network interface, such as 192.168.1.10 (IPv4) or 2001:db8::1 (IPv6).
What Is an IP Address in Linux?
IPv4 addresses are 32 bits written as four decimal numbers; IPv6 addresses are 128 bits written in hex. CIDR notation like /24 gives the prefix length, which defines the local subnet.
On Linux, ip addr shows addresses on each interface and ip route shows where traffic goes. Private ranges (10.x, 172.16-31.x, 192.168.x) are not routable on the internet and rely on NAT.
Example
ip -br addr
ip routeLearn more about IP Address
- IP Addresses Explained IP addresses are how devices on a network identify themselves. This guide covers IPv4 and IPv6 addressing, CIDR notation, public vs private addresses, subnetting basics, and how Linux assigns and displays addresses.
- IPv6 on Linux: Addresses, Autoconfiguration, and Why Your Firewall Might Be Open IPv6 is on by default and most people never configure it, which is exactly how a machine ends up firewalled on IPv4 and reachable on IPv6. Here is what the address types mean and what to check.
- Linux Networking Basics Understanding how Linux handles networking -- interfaces, IP addresses, routing, DNS, and the tools to inspect all of it -- is foundational for anyone administering a Linux system or working with servers.
Related tools
- Subnet Calculator Work out network, broadcast, host range, and masks for any IPv4 or IPv6 CIDR block, and split networks into subnets.