Werk #18213: Prometheus special agent: Circumvent maximum length of argument list

Component

Checks & agents

Title

Prometheus special agent: Circumvent maximum length of argument list

Date

Jun 27, 2025

Level

Trivial Change

Class

Bug Fix

Compatibility

Compatible - no manual interaction needed

Checkmk versions & editions

2.5.0b1 Not yet released	Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)
2.4.0p7	Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)
2.3.0p35	Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)

For very extensive rulesets for the Prometheus special agent the passed arguments could exceed the system limit for the argument list. This resulted in a OSError(7, 'Argument list too long'), which prevented the special agent from running.

This werk passes the more extensive parts of the data via a pipe to STDIN of the special agent instead of passing them as CLI arguments.

To the list of all Werks