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Title
Rule variable displaying as "null" in alarm message. -
Description
I am trying to get the following expression to work within a SQLServer rule-level variables:
pct_used = (#DBAllocUsedMB#/#DBAllocSizeMB#)*100
mb_free = #DBAllocSizeMB#-#DBAllocUsedMB#
Whenever I reference these rule variables in my alarm message, they always show up as null.
I have tried using the # syntax as well as scope.get(DBAllocSizeMB), but neither works. -
Cause
The assigned variables were referencing incorrect field names for the agents table.
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Resolution
1) Verify the field names for the agents table in the Web Console | Administration | Tooling | Script Editor
2) Select the Query drop-down for the agents table (in this example it was SQLServer_Database_323)
3) Select List Instances (select one of your deployed agents - Note: select any one of the unique IDs presented).
4) Review the Object Properties section and scroll down to view all the tables fields & values.
5) Make proper edits in the Rule Editor.
ie.
These variables are referencing the fields in the SQLServer_Database_323 table.
The mb_free & pct_used variables are referencing DBAllocSizeMB and DBAllocUsedMB which dont exist.
They should be DataAllocSizeMB & DataAllocUsedMB.
Entries as shown in the MonitoringPolicies file:
<expression name=pct_used>return ((#DBAllocUsedMB#/#DBAllocSizeMB#)*100)]] <----DB should be Data
<expression name=mb_free>#DBAllocSizeMB#-#DBAllocUsedMB#]] <----DB should be Data
Alternately:
1) Create a support bundle
2) Open the support bundle and view the MonitoringPolicies.xml file
3) Search for your desired rule
4) Review all the conditional and action statements.