We were given the task to create an aggregate alert for two different interfaces on two different devices. The alert is to trigger if the upstream or down stream exceeds 5Gbps for the two interfaces since its capable of a 10Gbps burstable but the company would be charged more.
This required some creativity as there was a few road blocks but it ended up being a custom SQL alert. The SQL itself is rather simple but I thought this may help some others who encounter the same or similar scenario.
The write up and how to is in our knowledge base, available here. If anyone has any questions just let me know.