Hello,
I have created a container named "Critical Nodes" and any object assigned to that container will have an attribute named "CriticalNode" set to 1.  When I get a node down alarm, I would like to check if CriticalNode equals 0 and set an alarm severity to warning or minor.  I am new to NetXMS.

Hello!

Probably easiest way is to create two rules in event processing policy, one for critical nodes and one for everything else, and set different severity to generated alarms. See attached screenshot for an example.

Best regards,
Victor

Thank you Victor, that worked perfectly.