Do not install Exchange Server 2003 on a Domain Controller

Do not install Exchange Server 2003 on a Domain Controller computer

Attempting to install Exchange Server 2003 onto a Domain Controller computer does create problems, including performance issues.

• The server cannot be a cluster. Exchange Server 2003 clusters which co-exist alongside Active Directory Servers will not be supported by Microsoft
• The server cannot just be Domain Controller, and will also need to be a Global Catalog server
• DSAccess/DSProxy/Cat will not fail-over or load balance to another Domain Controller or Global Catalog server.
• Use of the /3GB switch may cause the Exchange cache to use up the majority of system memory. It is also important that the number of user connections is kept to the minimum, this will also help in avoiding the need for the /3GB switch
• There is a security risk that could see services that are being run under LocalSystem being susceptible to security bugs. If a bug attacks Active Directory then it will also attack Exchange Server, and if one attacks Exchange Server then it will also be able to attack the Active Directory
• Administrators may be able to increase their permission levels within Active Directory as they are able to access the Domain Controller
• There will be an issue in the speed of server closedown as well. Times in excess of ten minutes are not unknown as the AD service (LSASS.EXE) will have to shut down prior to the shutdown of Exchange services. You will also find that DSAccess will timeout on several occasions before it will eventually shutdown. The only way to make this process faster is to have the Exchange services manually stopped before a computer shutdown is commenced

Article written by MyComputerAid.com