Maybe someone else will jump in and correct me, but I don't think it's possible to build this suppression. Suppression works by letting you specify a query; if that query matches any nodes, then the alert is suppressed (i.e., not triggered). But what you need for this purpose is a query that checks the state of two nodes.
I can't necessarily prove tdanner wrong, but you might try the following:
Add two simple conditions for the first node - one for system name and one for Node Status = Down.
Add a condition group using "all", then add two more simple conditions for the second node (system name and status)
I am thinking that thus will equate to having two sets of simple conditions connected by an ALL=AND statement so that if both nodes are down then the trigger will suppress.
Let me know if this works.
Sorry for such a late reply but I wanted to get back to you. I did try this and unfortunately it did not work. I think I tried every possible combo under the sun but it appears that tdanner was correct as I could not find any way to pull it off.
Instead I wound up keying off of the core switch stack at each location as that should always be available and 999 times out of 1000 if it's down then both lines are down.
Thanks for your help.