Usually the "status" item (as in "status.last(0)=...) is handled correctly if a system is monitored directly.

But a system behind a proxy is shown as "unreachable" all the time. A possible workaround is to change the trigger from

status.last(0)=2

to

agent.ping=0

I had rather expected that the 'status' parameter shows that a system is reachable - even when being located behind a proxy.