What command checks if a computer is online?
ping [IP or website]
What does DNS do?
Translates website names into IP addresses.
Difference between a switch and a router?
Switch connects devices inside a network; Router connects networks to each other or to the internet.
How do you see your computer’s IP in Windows?
ipconfig /all
How do you see your computer’s IP in Linux?
ip addr or ifconfig
What is the difference between TCP and UDP?
TCP is reliable and checks delivery; UDP is faster but doesn’t guarantee delivery.
What is a subnet mask?
Defines which part of an IP address is network vs host.
What is a default gateway?
The IP address where your device sends traffic to reach other networks.
Command to trace the route packets take to a server?
tracert (Windows) or traceroute (Linux)
What is a private IP address?
An IP used within a local network, not routable on the internet (e.g., 192.168.x.x).
What is a domain?
A central system that manages users, computers, and security on a network.
What is Active Directory (AD)?
A directory that stores users, groups, computers, and policies.
Command to list users in Windows?
net user
Command to reset a user password?
net user username *
Command to list groups?
net group
What is an OU (Organizational Unit)?
A folder in Active Directory to organize users and computers.
What is Group Policy?
Rules in AD that control users’ or computers’ behavior.
If a user cannot log in, what should you check first?
Network connection, account status, domain connectivity.
What is Kerberos?
A Windows protocol for secure authentication.
How do you join a computer to a domain?
System settings → change computer name/domain → type domain → enter credentials.
Command to check which user you are?
whoami
Command to create a new user?
adduser username
Command to change a user password?
passwd username
Command to see files in a directory?
ls -l