This note supplements CCNA Exam Topics 1.10

Different Operating Systems will use different interfaces and commands. In many cases you can accomplish the same goals via a GUI or a CLI, but which is better will depend on the particular system and your familiarity. While the broad strokes are usually the same, check the correct section for your system’s OS for the most relevant information.

Windows

CLI Commands

These commands can be run from Command Prompt, PowerShell, or Windows Terminal. For our purposes, the three are largely interchangeable.

  • ipconfig /all
    • Display basic configurations for each network interface on the device.
  • ipconfig /displaydns
    • Displays the DNS Cache. The whole thing. Expect a long output.
  • ipconfig /fushdns
    • Clear the DNS Cache.
  • ipconfig /release
    • Release IP address(es) automatically assigned by DHCP.
  • ipconfig /renew
    • Request a new IP address from the DHCP server.

Host File

Found at C:\Windows\System32\drivers\etc\hosts Contains a list of manually configured mappings of hostnames to IP addresses. Used as an alternative to DNS for mapping hostnames.

Note that the file has no file extension, and it should remain that way! You can still edit it with any normal text editor (notepad, for example).

Mac OS

CLI Commands

Mac OS’s command line app is called “Terminal”. Run these commands from there.

Linux

CLI Commands

There are a variety of flavors (distributions/‘distros’) of Linux, and the CLI commands for any one version may not work in another. Furthermore there are a multitude of Terminal applications (often called “Terminal Emulators”) available. Most distros will come with a default terminal app, usually called “Terminal”, “Console”, or similar. Any terminal emulator should work, but if you run into any trouble then you should seek support for your particular version of Linux.