Command Line Tools (N10-007)

ifconfig

A TCP/IP configuration and management utility used with UNIX and Linux systems.

traceroute

A TCP/IP troubleshooting utility available in Linux, UNIX and MacOS systems that sends UDP messages to a random port on the destination node to trace the path from one networked node to another, identifying all intermediate hops between the two nodes

ping

A TCP/IP troubleshooting utility that can verify TCP/IP is installed, bound to the NIC, configured correctly, and communicating with the network. Really though, it just sends ICMP echo requests to see if it can contact an IP address.

netstat

A TCP/IP troubleshooting utility that displays statistics and details about TCP/IP components and connections on a host. It also lists ports, which can signal whether services are using the correct ports.

nslookup

A TCP/IP utility that allows a technician to query the DNS database from any computer on the network and find the host name of a network node by specifying its IP address, or vice versa. This ability is useful for verifying that a host is configured correctly and for troubleshooting DNS resolution problems.

route

A command line tool that shows a host's routing table

iptables

A command-line firewall utility for Linux systems

tcpdump

A free, command-line packet sniffer utility that runs on Linux and other UNIX operating systems

dig

A utility available on Linux and macOS that provides more detailed domain information than nslookup

pathping

A windows utility that combines the functionality of the tracert and ping utilities to provide deeper information about network issues along a route, similar to UNIX's mtr command

tracert

A windows utility that uses ICMP echo requests to trace the path from one networked node to another, identifying all intermediate hops between the two nodes

nmap

A scanning tool designed to assess large networks quickly and provide comprehensive, customized information about a network and its hosts

ipconfig

Windows command that shows the IP configuration settings on a PC

arp

displays and modifies entries in the Address Resolution Protocol (ARP) cache