Server HDD Failure

[jftuga]

The "Microsoft Exchange Server Best Practices Analyzer Tool" recommends not running Exchange on a DC.

http://www.microsoft.com/downloads/details...&displaylang=en

-John

[cluberti]

i totally value what you say cluberti as you are so experienced, can you tell me why please?

Exchange is very poor at memory management, and also generally requires the use of the /3gb switch to make sure it's databases don't corrupt due to lack of virtual address space. This, however, halves the amount of kernel paged and nonpaged pool memory resources, as well as drastically limits the amount of available system PTEs required for memory operations.

Domain controllers require a lot of process address space and kernel paged and nonpaged pool resources, and also can require a good number of system PTEs for authentication and replication operation, especially lsass.exe.

If you're running Exchange, you are going to generally be using up lots of virtual address space (and thus RAM), as well as a good amount of kernel memory and PTEs. When running Exchange on a DC, something has to give when they both need resources - and it's usually your server, either when lsass.exe crashes and the server bugchecks or automatically reboots (because system security is lost when lsass.exe quits), or you start to get random Exchange database corruption due to lack of resources available to Exchange.

This happens so often that I wonder why this isn't more well-known, but I'll state it here for all - do NOT run Exchange on a DC, ever, unless it's SBS. SBS has been modified to do different things and run some things that a normal Windows server is NOT tuned to do.

There are reasons that there are limitations as to why we only allow up to 75 users in an SBS domain, and it is not (as you may start to understand as you run a DC, Exchange, and ISA on an SBS box) some draconian number meant to bleed you dry - it's actually somewhat technical in nature, as you can hopefully understand. SBS can only be tuned so far before you have to move away from the one-size-fits-all SBS server into more specialized servers that will run better when separated (like separate DC's and Exchange servers). SBS does a lot of things, and does them fairly well, but it does none of them very well like a dedicated server would.

Edited April 15, 2006 by cluberti

[nmX.Memnoch]

i was in discussion with someone today and he propose a HP ML360 to replace my current server, it would come with dual xeon process, 2.0GB RAM, 2 X 73GB RAID 1 for the OS and 3 X 142GB RAID 5 for the file.

we will also put in a new gigabit switch for the backbone, connecting the new and old servers, the firewall and adsl modem. The current ML150 server will be upgraded and use as a secondary backup incase the first server should fail. For a staff strength of 60 do you think this is good enough?

An equivalently configured Dell server will probably come in quite a bit cheaper.

Check out either a PowerEdge 1800 or PowerEdge 2800 (basically the same hardware but the 2800 can hold more drives). If you're looking for rackmount then those numbers translate to the 1850 (1U, 3 drives) and 2850 (2U, six drives).