Werk #18247: Certificate check: STARTTLS is now possible for SMTP

Component

Checks & agents

Title

Certificate check: STARTTLS is now possible for SMTP

Date

Oct 7, 2025

Level

Trivial Change

Class

New Feature

Compatibility

Compatible - no manual interaction needed

Checkmk versions & editions

2.5.0b1	Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT

When using "Check certificates", you can now select "SMTP STARTTLS" as connection type.

This allows checking the certificate of SMTP servers that require a STARTTLS procedure to use TLS (SSL).