Port monitoring for the services that don’t have a web page
Your database, mail server and SSH don’t answer HTTP. A port monitor opens a connection to the port they listen on and tells you, within a minute, when it stops being accepted.
Example check · demo data
Port monitoring checks whether a network service is accepting connections on a specific TCP or UDP port, such as 5432 for PostgreSQL or 587 for SMTP, and alerts you when it stops responding.
Common ports worth monitoring
Only expose a database port to monitoring if it’s already reachable from outside, and restrict it to StatusEagle’s addresses link IP list. Never open a database to the internet just to monitor it. Use a heartbeat from inside the network instead.
| Port | Service | Why monitor it | 22 | 25 / 465 / 587 | 53 | 443 | 3306 | 5432 | 6379 | 1194 / 51820 |
|---|---|---|---|---|---|---|---|---|---|---|
| SSH | Your way in when everything else is broken | |||||||||
| SMTP | Password resets, receipts and alerts depend on outbound mail | |||||||||
| DNS | If your own resolvers stop answering, everything looks down | |||||||||
| HTTPS | A lightweight check below the website monitor | |||||||||
| MySQL / MariaDB | The app can’t work without it | |||||||||
| PostgreSQL | Same, and connection limits are a common failure | |||||||||
| Redis | Sessions and queues often live here | |||||||||
| OpenVPN / WireGuard | Remote staff lose access silently |
How StatusEagle checks a port
Port monitoring vs ping vs HTTP
Layering them makes incidents faster to read: ping green, port red means the host is fine but the service crashed.
| Ping | Port | HTTP | Proves the host is reachable | Proves the service is listening | Proves the service responds correctly | Works for databases, mail, SSH | |
|---|---|---|---|---|---|---|---|
| Yes | Yes | Yes | |||||
| No | Yes | Yes | |||||
| No | No | Yes (status code, keyword) | |||||
| Partly | Yes | No |
Tips from running this ourselves
Related monitoring
Pair these monitoring checks to ensure complete stack coverage.
Frequently asked questions
Still deciding? Start monitoring free and verify your first service in ~2 minutes.
Port monitoring checks whether a service is accepting connections on a given TCP or UDP port, and alerts you when it stops.
Your first monitor takes about two minutes.
Free plan: 10 monitors, 3 locations, 1 status page. No credit card.