Recently, I was troubleshooting an issue with Nagios XI where host and service details where not being displayed from the web management console.
On investigating the log file at ‘/var/log/messages’ there was a number of errors identifying that a table in the MySQL database was crashed and was required to be repaired.
ndo2db: mysql_error: 'Table './nagios/nagios_timedeventqueue' is marked as crashed and should be repaired'
In order to repair the table marked as crashed, I ran the below on the Nagios XI monitoring server , reconnected to the web management console and both host and service details were displayed as expected.
myisamchk --safe-recover /var/lib/mysql/*/*.MYI
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