I am a programmer who has been bumped up to system admin. So my sysadmin knowledge is limited. We have several servers running Windows Server 2003. We need to replace one of the servers and the powers that be want the latest and greatest operating system. The domain controller will continue to run on 2003. Will 2008 play nice within this configuration or will it try to take over? We had an issue previously with trying to add in a server with Small Business Server 2003 that we ended up having to install standard 2003 on.
You should be fine bringing up a "member server" running Windows Server 2008. WS 2008 does run a different Active Directory than WS 2003, but as long as the WS 2008 server is not a DC, it won't change the AD schema or take over any of the AD "roles" and responsibilities. It can join a WS 2003 AD domain without problems.
Don't promote it to a DC until you are ready to use the new version of AD.
SBS 2003 wants to be a domain controller (that is part of the package) and generally does not play well with other Windows servers, particularly if it isn't the first server installed.
NOTE on server "modes": WS can (basically) exist in 3 modes.
- One is as a Domain Controller. You want more than one DC in a network and they need to be the same version of WS. Ideally they should be at the same patch/service pack level.
- Another mode is as a "member" of an AD domain. This mode allows the server to use AD authentication and permissions. This is what I recommend for the WS 2008 server in the WS 2003 AD domain.
- A third mode is "standalone"; not a member of a domain. This will also work in your situation, but the server will essentially be it's own domain, requiring it's own user and security management. I generally do not recommend this; administration is more difficult.
Small Business Server by default will try to be a domain controller, but if you're installing Windows Server Standard 2003 or 2008 it will play nicely with your existing domain unless you specifically want to promote it to be a domain controller. By default it will just be standalone unless you join it to the domain though.