Check manual page of mssql_blocked_sessions
MSSQL Blocked Sessions
This check lists all blocked sessions on a MSSQL Server. As
long at least one session is blocked, it will be CRITICAL.
This state is configurable with a default value of CRITICAL.
Alternatively you can configure thresholds for the SQL output
These two options can not be combined. If thresholds are set,
they will have precedence.
This check needs the Check_MK mssql.vbs -plugin installed in
the agent. Please refer to the online documentation
for how to install that plugin.
One check per host will be created