Question : 2nd domain controller for remote site

we've main site and remote in a single domain, and they are located diffrent subnet.  there is no any DC at remote site, all the networked equipment are connected to main site through P2P T1, VPN (DSL) as backup connection. in order to improve performance of site 2, I would like to promo one of file server at main site to DC and put it to remote site and setup this DC as primary DNS for all the workstation at remote site. Now, all the IP of remote site is assigned by the router (DG and DHCP server). I'm not pretty sure that will this scheme works.

Answer : 2nd domain controller for remote site

This is a simple enough proceess

Install Windows 2003 on the new machine

Assign the new computer an IP address and subnet mask on the existing network

Make sure that the preferred DNS server on new machine points to the existing DNS Server on the Domain (normally the existing domain controller)

Join the new machine to the existing domain as a member server

Promote the server to a domain controller by running DCPROMO from the command line - select "additional domain controller for an existing domain"

Once Active Directory is installed then install DNS. You can do this through Add/Remove Programs->Windows Components->Networking Services->DNS.  If you are using Active Directory Integrated DNS then DNS will br replicated from the other DC/DNS.

Next make the new machine a global catalog server, go to Administrative Tools, Active Directory Sites and Services, Expand, Sites, Default first site and Servers. Right click on the new server and select properties and tick the Global Catalog checkbox. (Global catalog is essential for logon as it needs to be queried to establish Universal Group Membership)

Install DHCP on the router and install DHCP on the new DC. You can do this through Add/Remove Programs->Windows Components->Networking Services->DHCP.

You will then need to remove any existing DHCP prior to authorising the new DHCP Server. When setting up the new DHCP server dont forget to set the default gateway (router) and DNS Servers. Talking of which all the clients (and the domain controllers themselves) need to have their Preferred DNS server set the new domain controller.

Both Domain Controllers by this point will have Active Directory, Global Catalog, DNS and the domain could function for a while at least should any one of them fail.

for best efficiency define the sites and subnets in Adctive Directory Sites and Services and move the new DC into the new site. Make sure that clients on each site point to their local DC as their preferred DNS server