The default uc500 config (using cca) puts fxo ports in a hunt group and applies the hunt group to the pots dial peers.
Problem is if one fxo trunk is oos, the hunt group does not hunt around .ie unplug trunk 1, and outbound calls are busy signals. Hard to believe the hunt group can't get around a failed trunk?
Whats the point of a hunt group?
I could just put preferences on the ports directly, but default config from cca builds hunt groups when you select the north american dial plan.