Use Orion Alert Manager to detect unstaible Nodes which goes up and down?

You can make use of the Advance Alert trigger condition tab,especially you can look for the "Custom SQL" option in the Type of property to monitor.This will allow to write any custom sql using the values from the Orion database.I suppose this should work for you.

  Can you provide an example of how we would use "Custom SQL" for this, especially for those of us who are not DBA's?

Similar to my other post: ">

The following would trigger for more than 12 node downs in 12 hours.

Type of Property to Monitor: Custom SQL Alert
Set up your Trigger Query: Node

WHERE
Nodes.NodeID IN (
  SELECT NetObjectID
  FROM Events
  WHERE  NetObjectType = 'N' AND EventType = 1 AND EventTime >= DATEADD(HOUR,-12,GETDATE())
  GROUP BY NetObjectID
  HAVING COUNT(1) > 12
)

EventType = 1 is the node down code (see the EventTypes table for a list)
DATEADD(HOUR,-12,GETDATE()) calculates 12 hours ago
NetObjectType = 'N' pulls only Node events
HAVING COUNT(1) > 12 for those that match more than 12 times (adjust accordingly)