Upgrading an Active Directory Domain from Windows Server 2003 to Windows Server 2008 or Windows Server 2008 R2
!!!NEVER START BEFORE HAVING CREATED AND TESTED A BACKUP OF YOUR DATA/MACHINE!!!
If you have installed Exchange 2003 in the domain see the following article first, Exchange requirements otherwise follow the steps below
- On the old server open DNS management console and check that you are running Active directory integrated zone (easier for replication, if you have more then one DNS server)
- run replmon from the run line or repadmin /showrepl(only if more then one DC exist), dcdiag and netdiag from the command prompt on the old machine to check for errors, if you have some solve them first. For this tools you have to install the support\tools\suptools.msi from the 2003 installation disk.
- run adprep /forestprep and adprep /domainprep and adprep /rodcprep from the 2008 installation disk against the 2003 schema master(forestprep) / infrastructure master(domainprep/rodcprep), with an account that is member of the Schema/Enterprise/Domain admins, to upgrade the schema to the new version (44) or 2008 R2 (47). On the Windows Server 2008 R2 disk are adprep32.exe (32bit) and adprep.exe (64bit) located, so make sure to use the correct version.
- see here about adprep in detail (http://technet.microsoft.com/en-us/library/cc731728(WS.10).aspx)
- you can check the schema version with "schupgr" or "dsquery * cn=schema,cn=configuration,dc=domainname,dc=local -scope base -attr objectVersion" without the quotes in a command prompt
- Install the new machine as a member server in your existing domain
- configure a fixed ip and set the preferred DNS server to the old DNS server only, think about disabling IPv6 if you are not using it, some known problems exist with it. Follow (http://blogs.dirteam.com/blogs/paulbergson/archive/2009/03/19/disabling-ipv6-on-windows-2008.aspx) to disable it
- run dcpromo and follow the wizard to add the 2008 server to an existing domain, make it also Global catalog and DNS server.
- for DNS give the server time for replication, at least 15 minutes. Because you use Active directory integrated zones it will automatically replicate the zones to the new server. Open DNS management console to check that they appear
- if the new machine is domain controller and DNS server run again replmon, dcdiag and netdiag (copy the netdiag from the 2003 to 2008, will work) on both domain controllers
- Transfer, NOT seize the 5 FSMO roles to the new Domain controller (http://support.microsoft.com/kb/324801) applies also for 2008), FSMO should always be on the newest OS DC
- after transfer of the PDCEmulator role, configure the NEW PDCEmulator to an external timesource and reconfigure the old PDCEmulator to use the domainhierarchie now. Therefore run on the NEW "w32tm /config /manualpeerlist:PEERS /syncfromflags:manual /reliable:yes /update" where PEERS will be filled with the ip address or server(time.windows.com) and on the OLD one run "w32tm /config /syncfromflags:domhier /reliable:no /update" and stop/start the time service on the old one. All commands run in an elevated command prompt without the quotes.
- you can see in the event viewer (Directory service) that the roles are transferred, also give it some time
- reconfigure the DNS configuration on your NIC of the 2008 server, preferred DNS itself, secondary the old one
- if you use DHCP do not forget to reconfigure the scope settings to point to the new installed DNS server
- if needed move the DHCP database to the Windows server 2008 machine, follow (http://support.microsoft.com/kb/962355), for more details see (http://technet.microsoft.com/en-us/library/cc772372.aspx)
Demoting the old DC (if needed)
- reconfigure your clients/servers that they not longer point to the old DC/DNS server on the NIC
- to be sure that everything runs fine, disconnect the old DC from the network and check with clients and servers the connectivity, logon and also with one client a restart to see that everything is ok
- then run dcpromo to demote the old DC, if it works fine the machine will move from the DC's OU to the computers container, where you can delete it by hand. Can be that you got an error during demoting at the beginning, then uncheck the Global catalog on that DC and try again
- check the DNS management console, that all entries from the machine are disappeared or delete them by hand if the machine is off the network for ever
- also you have to start AD sites and services and delete the old servername under the site, this will not be done during demotion
