Werk #20067: Windows agent: register agent updater during auto-registration
| Component | Checks & agents | ||||
| Title | Windows agent: register agent updater during auto-registration | ||||
| Date | May 27, 2026 | ||||
| Level | Trivial Change | ||||
| Class | Bug Fix | ||||
| Compatibility | Compatible - no manual interaction needed | ||||
| Checkmk versions & editions |
|
Previously, the Agent controller auto-registration ruleset (a
Checkmk Ultimate feature) did not register the Windows agent updater
even when the bakery option Agent Updater → Registration was
set to On first agent controller registration (keep) or On every
agent controller registration (overwrite). The agent controller
itself registered successfully; only the agent updater part was
skipped, and the controller logged:
You requested to register for automatic updates, but the Agent
Updater is not found. Skipping Agent Updater registration.
(check_mk_agent.exe not found in the same directory as
cmk-agent-ctl)
This has been fixed for new auto-registrations after the upgrade.
Hosts whose controller was already registered are not retried by
auto-registration (it only runs for not-yet-registered hosts). To
add the agent updater registration on such hosts, either de-register
the controller first (e.g. via cmk-agent-ctl.exe delete-all) and
let auto-registration run again, or register the agent updater
manually from the install directory:
cd "C:\Program Files (x86)\checkmk\service"
check_mk_agent.exe updater register -s <server> -i <site> ...
Technical background
Agent controller auto-registration runs under the agent controller daemon,
spawned by the Windows agent service from C:\ProgramData\checkmk\agent\bin\cmk-agent-ctl.exe.
The controller used to look for check_mk_agent.exe next to itself,
which succeeds for manual agent controller calls, but fails for the daemon
mode, since it's located only in the service's
installation directory at C:\Program Files (x86)\checkmk\service\.
The Windows service executable is now retrieved reliably via the registered binary path of the CheckmkService service.