CLI Networking Commands

The command-line tools network engineers, sysadmins, and power users rely on to diagnose connections, query DNS, scan ports, capture packets, and measure throughput. Start with a speed test to establish your baseline — then dig deeper with these tools.

Connectivity and Diagnostics

The ping Command

Test reachability, measure round-trip time, and detect packet loss with the most fundamental network tool.

traceroute / tracert

Map every router hop between you and a destination and find where latency or loss enters the path.

The pathping Command

Windows packet-loss testing by hop, combining ping and traceroute in one built-in tool.

The tracepath Command

Linux route and path MTU clues without root privileges.

The mtr Command

Combines traceroute and ping into a live display — the best tool for diagnosing intermittent packet loss.

The iperf3 Command

Measure actual TCP or UDP throughput between two hosts — the right way to benchmark a link.

DNS Lookup Tools

The dig Command

Query any DNS record type with full control over resolver, flags, and output format.

The nslookup Command

The cross-platform DNS lookup tool built into Windows, macOS, and Linux.

The host Command

Simple, readable DNS lookups — the fastest way to resolve a hostname from the terminal.

Network Interfaces and Routing

ipconfig and ifconfig

Display and manage network interfaces — the essential first stop when diagnosing a connection problem.

The ip Command (Linux)

The modern Linux tool for managing addresses, routes, and interfaces — replacing ifconfig and route.

The route Command

View and modify your system's routing table to control where traffic is sent.

The arp Command

View and manage the ARP cache that maps IP addresses to MAC addresses on your local network.

Connections and Port Scanning

The netstat Command

List active connections, listening ports, and per-protocol statistics — available on every OS.

The ss Command

The faster, more detailed replacement for netstat on modern Linux systems.

The netcat Command

Test TCP and UDP ports, create temporary listeners, and prove firewall reachability.

The ssh Command

Connect securely to remote shells, use key authentication, forward ports, and troubleshoot common SSH failures.

Telnet Port Testing

The old TCP connection trick that still helps when you need a quick port check.

The netsh Command

Windows network reset, WLAN, IP, Winsock, and firewall diagnostics from Command Prompt.

networksetup on macOS

Manage DNS, Wi-Fi, proxies, and service order from Terminal.

The nmap Command

Discover hosts and open ports on a network — the standard tool for network inventory and security audits.

Packet Inspection and HTTP

The tcpdump Command

Capture and inspect live network traffic from the command line — essential for deep protocol debugging.

Wireshark Basics

Capture packets without drowning in them: filters, retransmits, DNS, TCP, and privacy warnings.

The curl Command

Make HTTP requests, test APIs, download files, and inspect headers directly from the terminal.

The wget Command

Download, resume, test headers, and check URLs from the terminal.

The whois Command

Look up domain registration details, IP ownership, and ASN information in one command.