Advanced TCP Monitoring
Confirm a service actually answers correctly — not just that its port is open.
Advanced TCP Monitoring adds TCP over TLS, send/expect validation and banner capture to TCP checks: connect to a TLS-wrapped port such as SMTPS, send a fixed payload, and require a matching reply — plain text or a regular expression — before the check passes. With banner capture on, the service's reply line is recorded so you can see its greeting or version and when it changed.
What it detects
- A service that accepts the connection but answers wrongly (e.g. send PING, require PONG)
- A protocol banner that changed or disappeared — an SSH or SMTP greeting with a new version
- TLS handshake failures and an expiring certificate on TLS-wrapped ports
How you're alerted
- A failed exchange fails the probe, so the automatically attached “TCP Down” rule fires.
- A diagnostic check is captured when the monitor goes down: connection, TLS handshake and expected reply shown separately, with the lines the service sent.
Notifications go to any of 8 channels — see notifications.
- Runs from
- Every probe region you assign — down only when all of them agree
- Adds to TCP
- TCP over TLS (optional skip-verify for internal services), send/expect with regex, banner capture
- Banner capture
- For services that speak first or answer your send text (SSH, SMTP, IMAP…) — a silent port such as HTTP would time out
- Available on
- Professional · Enterprise and Custom on request
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