Monitoring Backend not running

I get the error “Monitoring Backend not running” in the Icinga web interface.

icinga2.log shows:

[2024-08-20 22:44:44 +0200] critical/IdoMysqlConnection: Exception during database operation: Verify that your database is operational!
[2024-08-20 22:44:54 +0200] critical/IdoMysqlConnection: Connection to database ‘icinga2’ with user ‘icinga2’ on ‘localhost:3306’ failed: “Access denied for user ‘icinga2’@‘localhost’ (using password: YES)”
Context:
(0) Reconnecting to MySQL IDO database ‘ido-mysql’

When I do “validate” under Monitoring Backend settings, though it seems to be able to connect fine:

Validation Log
Connection to icinga2 as icinga2 on localhost: successful
have_ssl: DISABLED
protocol_version: 10 version: 10.11.6-MariaDB-0+deb12u1
version_compile_os: debian-linux-gnu

Same goes when I manually connect to the database via commandline, works fine:

: mysql -u icinga2 -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 40
Server version: 10.11.6-MariaDB-0+deb12u1 Debian 12

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the current input statement.

MariaDB [(none)]> use icinga2;

Database changed
MariaDB [icinga2]> show tables;
±---------------------------------------+
| Tables_in_icinga2 |
±---------------------------------------+
| icinga_acknowledgements |
| icinga_commands |
| icinga_commenthistory |
| icinga_comments |
| icinga_configfiles |
[…]

Why can’t icinga daemon connect to the db when the webinterface test can and it’s also working on the commandline?

Hmm it seems because the password that is put into the webinterface Backend configuration dialog does not seem to make it to the config files (?)

/etc/icinga2/features-enabled/ido-mysql.conf contained the wrong mysql db password, after changing it, it’s working now.