Poichè è nota la mia innata antipatia per Microsoft Exchange, mi trovo spesso a discutere con dei fan di Exchange sulle lacune che ha questo prodotto. Purtroppo la maggior parte delle persone non ha mai usato seriamente altri prodotti e usa la pappa pronta di mamma Microsoft, quindi è difficile fare con loro dei confronti con altri Mail Server. Mi viene spesso detto che il grande vantaggio è l’integrazione con Active Directory, ma per esperienza personale so che questo può anche essere uno svantaggio, in particolare quando bisogna migrare da Windows 2000 Server a Windows Server 2003 (piccolo O.T. mi fa sempre sorridere il fatto che la parola Server venga posizionata diversamente a seconda delle due versioni, ma io non sono un genio del marketing e quindi non posso capire ).

Chi mi fa andare in bestia sono le persone, considerate degli esperti, che nei Forum consigliano di installare Microsoft Echange Server 2003 su un Domain Controller, quando la stessa Microsoft lo sconsiglia (per non parlare dei siti dei veri esperti del prodotto in oggetto).

Microsoft Exchange Server TechCenter
Running Exchange 2003 on a Domain Controller

As a best practice, you should not run Exchange 2003 on servers that also function as Windows domain controllers. Instead, you should configure Exchange servers and Windows domain controllers separately.

However, if your organization requires that you run Exchange 2003 on a domain controller, consider the following limitations:

If you run Exchange 2003 on a domain controller, it uses only that domain controller. As a result, if the domain controller fails, Exchange cannot fail over to another domain controller.

If your Exchange servers also perform domain controller tasks in addition to serving Exchange client computers, those servers may experience performance degradation during heavy user loads.

If you run Exchange 2003 on a domain controller, your Active Directory and Exchange administrators may experience an overlap of security and disaster recovery responsibilities.

Exchange 2003 servers that are also domain controllers cannot be part of a Windows cluster. Specifically, Exchange 2003 does not support clustered Exchange 2003 servers that coexist with Active Directory servers. For example, because Exchange administrators who can log on to the local server have physical console access to the domain controller, they can potentially elevate their permissions in Active Directory.

If your server is the only domain controller in your messaging system, it must also be a global catalog server.

If you run Exchange 2003 on a domain controller, avoid using the /3GB switch. If you use this switch, the Exchange cache may monopolize system memory. Additionally, because the number of user connections should be low, the /3GB switch should not be required.

Because all services run under LocalSystem, there is a greater risk of exposure if there is a security bug. For example, if Exchange 2003 is running on a domain controller, an Active Directory bug that allows an attacker to access Active Directory would also allow access to Exchange.

A domain controller that is running Exchange 2003 takes a considerable amount of time to restart or shut down. (approximately 10 minutes or longer). This is because services related to Active Directory (for example, Lsass.exe) shut down before Exchange services, thereby causing Exchange services to fail repeatedly while searching for Active Directory services. One solution to this problem is to change the time-out for a failed service. A second solution is to manually stop the Exchange services before you shut down the server.

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Why is it NOT recommended to install Exchange Server 2003 on a computer that is also a Domain Controller?

Exchange on a DC