We have a parent and child domain setup. All was working well till a week ago when the DNS server in the parent domain crashed and had to be rebuilt. Eversince then, the child DNS is not able to get updates (unless manually initiated from Replication Monitor) from the parent. Approx. every 7-8 hours, the zone for the parent expires causing some App's to be unavailable.
Even after a manual replication as mentioned above, the newly updated zone file in the child DNS is missing a WWW "A' record that DOES exist in the parent DNS. I am not clear as to why that is the only record that is not replicated time after time.