Latest Troubleshooting topics

Topic	Replies	Views	Activity
Troubleshooting FAQ This is a Wiki topic for troubleshooting Checkmk. Feel free to contribute! Template for troubleshooting posts Here is the post template that you can use to make your issue clearer to everyone. Just edit out the sample p…	1	5072	October 31, 2019
About the Troubleshooting category	3	1784	October 30, 2019
Webgui stopped working - Apache proxy error - undefined symbol: EVP_idea_cbc, version OPENSSL_3.0.0	4	127	June 19, 2026
Why was a specific contact notified about an event on a host? notifications , checkmk-v2	3	61	June 19, 2026
Sendmail fatal error	2	29	June 19, 2026
"Disabled services" rule causes massive "Unimplemented check ... service could not be found" warnings flooding nagios.log (Nagios core) checkmk-v2-5 , checkmk-raw	0	18	June 18, 2026
UP/DOWN Status of Docker Containers not Updating docker	13	137	June 18, 2026
“Unknown password type.” when trying to add AWS S3 Backup Target	8	73	June 18, 2026
SQL Plugin cannot find data for SQL jobs agent , mysql , checkmk-v2-1	4	482	June 18, 2026
MariaDB replication monitoring - need to add additional permissions on Debian Trixie+	1	28	June 18, 2026
Plugin cisco_qos uses 32bit counters instead if 64bit counters checkmk-v2-4 , bug , checkmk-raw , checkmk-v2-1	0	18	June 18, 2026
Error when tring to monitor or ignore sensor	8	48	June 18, 2026
"cmk -N" not working in 2.5 checkmk-v2-5	5	145	June 18, 2026
CheckMK 2.5 Swagger Yaml File Returns 404 on download checkmk-v2	3	60	June 18, 2026
2.5.0p6 ultimatemt not useable on el9 for new sites	3	54	June 17, 2026
Macro variable not working for check-mk 2.4 checkmk-v2-4 , checkmk-raw	1	25	June 17, 2026
SNMP Discovery failure (badValue) checkmk-v2-1 , checkmk-v2	2	44	June 17, 2026
Monitoring SSL Certs with "Check Certificates" checkmk-enterprise	4	243	June 16, 2026
ModuleNotFoundError: No module named 'cmk.utils.debug'	4	30	June 16, 2026
NagVis hover popup missing service list and status after update to 2.4.0p30 nagvis	3	52	June 16, 2026
Update to CMK 2.5 fails: Update aborted with Error: 'credentials'	0	28	June 15, 2026
Check_httpv2 cert check on own CA webservices: error trying to connect: invalid peer certificate: UnknownIssuer checkmk-raw , checkmk-v2	31	5625	June 15, 2026
Slow folder trees with hosts since upgrade to 2.5.0p5 checkmk-v2-5	1	28	June 15, 2026
SNMP Timeout > 60 sec – multiple devices affected checkmk-v2-4 , checkmk-enterprise	1	45	June 15, 2026
CHeckmk still try to use sendmail instead of my script , which cause failed notification checkmk-v2 , checkmk-v2-1	7	76	June 15, 2026
2.4.0p29 - RTA name from check_ping Nagios plugin is mangled and its perf-o-meter is missing	1	36	June 15, 2026
Updated to 2.5.0p2 - Parsing of section qmail_stats/iis_app_pool_state failed checkmk-enterprise , robotmk	5	87	June 15, 2026
Notes Domino Checks unknown after Domino Update	4	66	June 15, 2026
Brocade SFP monitoring --wrong values checkmk-v2 , checkmk-v2-2	3	44	June 14, 2026
discover windows service by agent checkmk-v2	1	33	June 13, 2026

Troubleshooting FAQ

This is a Wiki topic for troubleshooting Checkmk. Feel free to contribute! Template for troubleshooting posts Here is the post template that you can use to make your issue clearer to everyone. Just edit out the sample p…