We have AD on 2008R2 implemented and working fine. We have ONE Forest and 3 child domains city1.domain.lan, city2.domain.lan, city3.domain.lan with rootdc.domain.lan being the forest master. Forest functional level is Windows 2003.
I have recently inheritted this setup and my initial findings reveal that the child domains are not resolving DNS name lookups for external requests, rather the previous sys-admin was distributing DC IPADDRESS, 18.104.22.168 and 22.214.171.124 as DNS servers.
There are no forwarders configured on the DC DNS MMC, moreover the DC cannot browse the internet due to security reasons, they have a VPN tunnel connected to root site for replication but all other traffic is disabled on that circuit - so no internet connectivity for the DC itself - hence no external DNS lookups.
As they have around 500 - 700 Users and considering everyone is getting 126.96.36.199 and 188.8.131.52 for external dns lookups, I am thinking that would be a lot of requests going out there Internet Link for DNS (53).
Q1 - Do you think I should implement a windows based DC joined to the child domain for external look ups or the above setup seems ok?
Q2 - What do I look for to verify whether the DC is replicating fine (repadmin ?)
Q3 - I checked Sites and Services but I am not very good in AD and have to learn - so would be grateful if you could let me know what to look for ?
Q4 - I used AD topology diagrammer and it says Intersite Replication disabled ? Is this harmful ?
I will post more details about the AD topology and if one could let me know what to provide as info - I will do my best to get the question updated ASAP
Your help would be grately appreciated