MSSQL Log Cache Hit Rate

[jameyw]

We had a UP fail last week and as a result, my entire data center lost power. Once I got everything back up and running I get Critical notifications for two of my MSSQL databases:

CRITICAL: Log Cache Hit Ratio is 98.624329942%.

The server seems to be OK and I don't see any performance issues but I can't really tell if this is a problem with the database or if it is with the query in NagiosXI. Prior to the outage, I was not receiving any notifications. To make matters more confusing, articles I find online regarding Log Cache Hit Rate seem to indicate these numbers should be high, indicating the transactions are hitting the cache more and are requiring less disk I/O. I'm not an expert in MSSQL so that doesn't help matters either.

Here is the command associated with the service:
check_xi_mssql_database!-U 'user' -P 'password' -T 'databasename' -p 1433 --logcachehit --warning 0:95 --critical 0:97!!!!!!!

Thanks in advance.

[lmiltchev]

I'm not an expert in MSSQL, either and I am not familiar with your specific environment, but I can tell you that you are getting a CRITICAL output as the "Log Cache Hit Ratio" value exceeds your critical threshold of 97.

check_xi_mssql_database!-U 'user' -P 'password' -T 'databasename' -p 1433 --logcachehit --warning 0:95 --critical 0:97!!!!!!!

You can either fix the issue on the server or increase the thresholds according to your environment/needs.

Read more on the threshold and ranges here:
https://nagios-plugins.org/doc/guidelin ... HOLDFORMAT