Which UNIX/Linux command can display basic TCP/IP information? Best single command.

• A. ifconfig
• B. ip
• C. ifconfig and ip
• D. route

Answer: (B)

The essential idea is to use the ip command from the iproute2 suite, which is the modern, unified way to inspect TCP/IP settings. This single tool lets you see the key pieces of information you usually need: which interfaces exist, what IP addresses (IPv4 and IPv6) are assigned, and how traffic would be routed.

To view addresses on each interface, use the subcommand that shows addresses: ip addr (often abbreviated as ip a). This reveals the interface names, the assigned IPs, their prefix lengths, and the broadcast where applicable. If you also want to check the status of the interfaces themselves (up, down, and other link-level details), ip link provides that information. For routing information, ip route shows the current routing table.

The advantage over older tools is that iproute2 combines these capabilities in a single, consistent interface, and it’s the recommended tool on modern systems. Older utilities like ifconfig are often deprecated or incomplete, and route focuses only on routes without providing the fuller picture of interfaces and addresses. So, using ip gives you a comprehensive view of basic TCP/IP configuration with a single, cohesive command family.