Guidance on Active Directory design for Exchange Server 2007
With Exchange Server 2007, Microsoft recommends that you deploy one 32-bit GC CPU core for each four Exchange 2007 mailbox server CPU cores.
You must have enough RAM installed on the 64-bit server to cache the entire Active Directory database in memory.
On a 32-bit machine, no matter how much RAM you install, you’re unlikely to be able to cache the whole database unless it is less than 1.5-1.7 GB in size.
(If you’re thinking, well, my AD database is a couple of gigabytes in size, but what if I were to use the /3GB switch to get some extra 32-bit address space for cache? Theoretically, yes, you can increase the amount of cache this way. As a practical matter, you would likely only get about 2.5-2.7 GB consistently in cache, and that would come at the price of system stability. Use of the /3GB switch on domain controllers is discouraged because it is likely to starve the machine of critical kernel resources. When this happens, the typical result is that after several days or weeks of operation, or after a peak in client demand, the server becomes unstable or unresponsive.)
RAM & Event log size
the event log service is using memory mapped files, but No process can have more than 1GB of memory-mapped files in total.
Q: If we wanted to use StaticDomainControllers and StaticGlobalCatalogs, how can we definine multiple Domain Controllers and Global Catalogs?
A: set-exchangeserver -id <E2K7 server> -staticDomainControllers ‘dc.domain.com’, ‘dc2.domain.com’