Hi there
Active Directory is designed to be installed on more than one server in a
domain to provide fault-tolerance. If you only have one DC at the moment,
you should consider adding the new server and leaving the old one in place.
Before you do this, you need to check your DNS is correctly configured
across your whole network.
Check that the following is true to make this go smoothly.
1) DNS is installed on your existing domain controller
2) Your existing DNS is active directory-integrated
3) Your existing DC has itself as the only DNS server in its TCP/IP
configuration
4) Your workstations have only existing domain controller's IP address in
their TCP/IP configuration
5) Your DNS server uses a forwarder to provide DNS resolution of external
addresses.
6) You configure your workstations' TCP/IP using DHCP only
If the above are all true, then that's fine. Otherwise, do some reading and
thinking.
The following will work for your small network.
1) Perform a full backup
2) And again
3) Check your backups are good.
4) Install the OS on your new server.
5) Configure the new server's TCP/IP data to point DNS at the existing DC
only.
6) Add the Microsoft DNS server to your new DC. No need to do any
configuration yet.
7) Ensure your DNS domain name is correctly-recorded in the TCP/IP config on
your new DC.
8) Run dcpromo and add the new server as an extra server in the existing
domain.
9) When the wizard has finished and you've restarted, switch the DNS server
to active directory integrated DNS.
10) Using the nslookup tool, use the "server" command to switch to your new
DNS server. Type the name of each DC to check that DNS information has
replicated fully. It would not harm to do some additional testing at this
point.
11) Change the new DC to point to itself only for DNS in the TCP/IP config
and reboot.
12) Transfer the operations master roles as appropriate.
13) Change DHCP to include both DNS servers. Depending on your plans, you
may want to install DHCP on your new server and disable it on the old one.
If you really do want to remove the old server and leave yourself with only
one (not advisable), I'd be inclined to wait a few days before demoting it.
You use dcpromo for the demotion task as well.
Hope this helps
Oli
