if router is down alert only the router and not the switch and AP
if the switch or the AP is down alert only switch or AP.
There is a feature in Orion called Dependencies, which provides this function. Essentially you define that a Child's objects status is determined by he state of it 'Parent', whereby if the Parent is down, the Child object/s are placed in to state called 'UnReachable'. Therefore, an alert defined that has trigger as being 'Status is equal to Down' will not be triggered.
Tip: Create a Group for the AP and Switch (and any other tier 2 devices) and use that as the 'Child' object.
As an addendum to m_roberts reply you can also turn on auto-dependencies on a platform wide basis. This will take the hassle out of creating them all for a large environment. See this KB article for how.
The caveat here is that SolarWinds doesn't always get these right, so you can then create a manual one as per Marks answer, which overrides the auto-dependency.
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