Sites in DNS Server not replicating

We have DNS server running on our domain at our main site. We have 4 remote sites connected via a vpn. So we have a domain controller at each location. DNS server is setup on each of those servers as a secondary zone to the main DNS server at our main location.

Weird thing going on, on our main DNS server, it shows all the computers and IP's of the main site and only two of the remote sites. However, the two remote sites that are not showing up, it at least shows the server for each site.

Now if you go to the remote site server and look at that DNS server, it shows all 5 sites and their computers and IP's.

Why would our primary DNS server be missing the two sites?

Solution 1:

If "DNS server is setup on each of those servers as a secondary zone" then this zone is not Active Directory-integrated.

I need to check this but I thought secondary zones were read-only even in Windows DNS server. Assuming dynamic DNS updates, clients attempt to register their records with their primary servers, which is probably the DC at each site, depending on how you have configured your DHCP. If you really have those servers configured as secondary servers then they won't accept updates (?) and no zone transfers will be pulled by the master DNS server.

Something doesn't make sense here - can you add detail to the question?

Solution 2:

Sounds like a replication issue. Go into "Active Directory Sites and Services" and verify that your main site is configured with links to pull info from your remote sites. Sounds like you have AD-integrated DNS so I believe replication happens through AD.