Problem excluding nodes in trigger condition

Question

I am having difficulty with a particular alert trigger condition, and I'm hoping the community may be of assistance. The alert in question is meant to trigger when a node has rebooted. However, a few nodes in our environemtn restart their SNMP services on a nightly basis--a seperate issue we are working to resolve--and I want to exclude these nodes from the reboot alarm. I have implemented the following trigger condition, but I am still getting alerts on the two nodes grouped under the last, None condition. I am at a loss to explain why this is happening. Can anyone out there shed some light on the problem?

Many thanks in advance!

superfly · Answer

"None" would work if you only have 1 condition under it. As you have 2 conditions, it will still trigger the alert. Which is why you have to use "Not All"

Here's the details from the help file.

None Condition Group

Changing the condition group to Trigger Alert when none of the following apply means that all 
conditions in the group must be false before the alert is triggered.

In this example the alert trigger would read:

Alert when: (Node Status = Down) and (Percent Loss <= 75) and (CPU Load <= 85)

Each condition is separated by an and statement just like the all condition group; however, the conditions have been 
inverted (Node Status = Down instead of Node Status = Up).

Not All Condition Group

Changing the condition group to Trigger Alert when not all of the following apply means that any 
condition in the group must be false before the alert is triggered. So, in this 
example the alert trigger would read:

Alert when: (Node Status = Down) or (Percent Loss <= 75) or (CPU Load <= 85)

Each condition is separated by an or statement just like the any condition group; however, the conditions have been 
inverted (Node Status = Down instead of Node Status = Up).

bsciencefiction.tv · Answer

If you are comfortable with SQL,  gave me this  tip: if you change the rule to be a custom SQL alert you get the syntax being used, which often exposes the translation...

rprovost76 · Answer

Thank you! I have implemented the suggested change and will wait to see if it does what I need it to do. I can't say I fully understand the difference between Not All and None in the logical conditions, so I will do some additional reading to get a clearer understanding.

Thanks again for your assistance.