Connection Refused vs Reset vs Timed Out: What They Mean
Connection refused, reset, and timed out mean very different things. What each error reveals about where a failure is, and how to monitor and debug them.
How to Check if a Port Is Open (Windows, macOS & Linux)
Check if a port is open with telnet, netcat (nc), nmap, PowerShell Test-NetConnection and /dev/tcp on any OS — plus how to monitor ports continuously.
Server Monitoring Basics: Uptime, Reachability, and Response Checks
Server monitoring starts with uptime, reachability, and response checks. Learn what to monitor first and how to catch failures before users notice.
Port Monitoring: How to Check if a Server Port is Open and Responding
TCP port monitoring catches service failures that HTTP checks miss. Learn which ports to monitor and how to alert when they stop responding.