I have a query which I hope someone out there could help with. If I
explain the problem

Site A - ServerA – ip:
Site A - ServerB – ip:
Site A - ServerC – ip:
Site B - ServerB – ip:
Site C - ServerC – ip:
Site D - ServerD – ip:

All server are at different sites connected by WAN links. All IP only
network and us

I have a DNS entry for my tree CO_TREE-

The problem is If site D loses its WAN connection, users from this site
can no longer logon/authenticate as they can no not resolve CO_TREE which
is across the WAN link.

SLP is configure and working.

Should I be setting a DNS entry for my tree?