default Health check port ranges & how exclude using some port

As Odaah said, should be high ports (1024-65535). I could't find any way to change that, neither via monitor or db keys for bigd.

However, if you disable port reuse for bigd, the monitor should fail only once (when uses the blocked port). As the default monitor settings (and F5 recommendation even if you change), is to have 3 fails before the member is marked down, it should not mark the pool member down.

Solution about socket reuse:

https://support.f5.com/kb/en-us/solutions/public/13000/800/sol13820.html