ping example.com
Tests connectivity to a server by sending ICMP echo requests. Shows round-trip time and packet loss.
tracert example.com
Shows the route packets take to reach a server, including all intermediate hops.
ipconfig /all
Displays detailed network configuration including IP address, DNS servers, and DHCP information.
nslookup example.com
Queries DNS servers to find IP addresses for a domain name.
nslookup -type=MX example.com
Finds mail server (MX) records for a domain.
DNS resolution is like a phone book for the internet, translating domain names to IP addresses.
ipconfig /release
Releases the current DHCP lease and IP address.
ipconfig /renew
Requests a new IP address from the DHCP server.
If you see an IP address starting with 169.254.x.x, it means DHCP failed and you're using a self-assigned address.
systeminfo
Shows detailed system information including CPU, RAM, and OS version.
tasklist
Lists all running processes and their memory usage.
wmic cpu get name
Shows the CPU model name.
nslookup -type=MX gmail.com
Finds Gmail's mail servers.
telnet smtp.gmail.com 587
Tests connection to Gmail's SMTP server (email sending).
Email servers use different ports: 25 (SMTP), 587 (Submission), 993 (IMAP), 995 (POP3)