Introduction

I’ve noticed some confusion regarding the differences and reasons to migrating to Exchange 2000 from Exchange 5.x, and wanted to clarify some of the primary differences between the two products. This article will clarify SOME of the differences, without launching into an exhaustive feature comparison. Most 5.5 Admin’s would like to know what the beef is with this new, improved, and safe for fabric’s version of Exchange . Lets look at some areas where were likely to notice the largest differences from an Exchange administrators point of view:

Storage and Scalability

Exchange 5.5 is able to support two databases per server: public – public folders and private – mailbox store.

Exchange 2000 is able to support four Storage groups housing five databases EACH. If you do your maths correctly, this results in a possible 20 stores PER machine.

This has a massive impact on server scalability and consolidation. Why? Well consider the fact that the change in storage organisation allows you to consolidate three or four mail stores onto one machine and more – depending on the “beefiness” of your box. I’m currently running 16 databases on an active-active cluster, supporting more than 308GB of mail, excluding Public Folders. The only limiting factor is storage and backup windows, while each node is well capable of supporting in excess of 2000+ clients.

Directory and Administration

One of the first benefits that come to mind is Mailbox Moving Without Borders. Yes oh fearless messaging admin – you are finally able to move a mailbox From anywhere, To anywhere. Yes really. No more exporting and importing to PST’s. If you’ve got the bandwidth to do it  - you can.

User mail admin now occurs through the user administration tool, while Exchange admin occurs via a number of tools, most MMC based for your viewing pleasure. AD hosts configuration info for each server and for global settings, adding and offloading resilience issues from yourselves.  Administrating this product is one of the first differences to hit the admin out of the box. Lots of things have been centralised to the directory and permission based task delegation and different Exchange administrator levels are supported. An example of this is that trigger happy Bob can now only VIEW Exchange information for the enterprise, while remaining able to administer public folders only.

Unified directory – only one directory to manage. Directory replication is now offloaded to AD. Since AD (Active Directory) hosts the configuration and user information of Exchange, there is no need for a separate Exchange directory. Since AD is LDAP addressable (LDAP support exists for Ex 5.5 as well after SP3), updating users in bulk is much easier than before. Several third party products exist to enforce directory content, further offloading administrative tasks. A plethora of material has been written around this, so I won’t expand much more unless asked.