Werk #19012: Reuse comment and downtime IDs

Component

Core & setup

Title

Reuse comment and downtime IDs

Date

Nov 20, 2025

Level

Trivial Change

Class

Bug Fix

Compatibility

Compatible - no manual interaction needed

Checkmk versions & editions

2.5.0b1	Checkmk Pro, Checkmk Ultimate, Checkmk Ultimate MT
2.4.0p17	Checkmk Pro, Checkmk Ultimate, Checkmk Ultimate MT
2.3.0p42	Checkmk Pro, Checkmk Ultimate, Checkmk Ultimate MT

The core now reuses free comment and downtime IDs. This prevents ID space overflow.

This prevents errors when modifying downtimes via a livestatus connection.

Existing downtime IDs remain unchanged, so users do not need to take any action.