One of the biggest changes in Microsoft's thinking is that Exchange 2007 now has
five server roles. This passion for 'Roles' mirrors Microsoft's
philosophy of 'Customize This Server' on Windows Server 2008.
At one extreme you could deploy a single 2007 Server with four roles and forget about the
Edge (Gateway) server role. At the other extreme you could have five separate
Exchange servers, one for each role. Microsoft call this increased scalability, I think of it more as increased flexibility.
Exchange 2007 with its five roles, and greater 64-bit power, will benefit
those who have a clear plan of what they want to achieve with their email servers. In retrospect it could be argued that Exchange 2000 and 2003 tried to be all things to all people.
As a result add-ons like
Conference Server and Instant Messaging are not available, instead Exchange
2007 concentrates on being a premier email server.
Exchange 2007 -
Five Server Roles
In previous versions of Microsoft Exchange Server you could not select
specific roles, because all features were installed on each server.
Exchange Server 2007 uses the concept of server roles to control which
capabilities are installed on which Exchange server. The benefit of
this new arrangement is improved scalability, better security and simplified
administration.
Note: Exchange Server 2007 should be installed on a
member server, and not a domain controller.
Mailbox is a good name for the core server, which stores all the email. Incidentally, remember to install IIS and the World Wide Web (WWW) service. Deploying a Mailbox Server
linked to CAS (Client Access Server) would be like pairing the Back-end / Front-end
servers in Exchange 2003.
One surprise is that Mailbox servers do not transfer messages between mailboxes,
for this message delivery you need a Hub Transport server. Bear this in
mind when troubleshooting non-delivery of internal email. For smaller
Exchange Organization you could combine the Mailbox and Hub Transport roles
on the same server.
From a planning point of view, consider SAN (storage area network) for Mailbox
servers to improve performance, availability and backup.
See more on the Mailbox Server Role
The
Client Access Server (CAS) is installed by default. Plan to have for a
Client Access server in each site that has an Exchange 2007 mailbox server.
Your main clients will probably be desktop machines running Microsoft Outlook
2002 or later.
Other client types include POP3, IMAP4, Exchange ActiveSync, Web, and Outlook
Anywhere.
In terms of transition from Exchange 2003 servers, CAS replaces those front-end
servers. As expected CAS also supports OWA (Outlook Web Access) clients.
The Client Access Server also supports Autodiscover. For those who require
internet access then configure and ISA server to manage the transition across
the firewall from internet to internal network.
See more on the CAS Role
The hub transport role replaces the old routing connectors. Smaller organizations would probably add this role to the Mailbox
Server or
possibly the Client Access server. The key point is that even for
large organizations, the Hub Server manages the delivery of all internal
Exchange 2007 email. At its heart, the Hub Server has a categorizer, which
analyzes each email and delivers it to the appropriate mailbox.
Hub Servers also have a Journaling Agent. You have the technical ability
to save a copy of all email, how much, or how little use you make of this
facility is best discussed with your company lawyers.
This server hosts the integration of voice (voice-mail), calendar, email and fax. Unified messaging enables
voicemail and faxes to be delivered to the Outlook 2007 (Version 12) inbox. This role needs
'speechify', most likely the wizard will install it automatically.
This Edge Transport (Gateway) server is a new development for
Microsoft's Exchange. Think of the
Gateway server as the hygiene server, as a rival of Message Labs or as a replacement for your third party email cleaning service. An absolute requirement is that the
Edge server must be in it's own
workgroup and must not, repeat not, be a member of the Exchange Organization's Active Directory domain. For this reason the Role Selection wizard displays a horizontal separator between this and the
other server roles.
For a variety of reasons the Edge server has proved to be the least popular
Exchange Server 2007 role. This is especially true in the UK where people
rely on other solutions to clean mail and act as a gateway to the internet.
See more on the Edge Server Role
Exchange Server 2007 Two Editions - Standard and Enterprise
Exchange Server 2007 is available in two editions, Standard and
Enterprise. The Enterprise Edition supports 50 storage groups (50
databases), whereas the Standard Edition supports only 5 storage groups (5
databases). However, in a departure from previous version, Exchange
2007 has no software limit on the database storage, each storage group
database can be as big as you like. In Exchange 2003 Standard edition,
the limit was 16Gb or 75Gb.
Exchange Server 2007 is a complex topic, do you need practical hands on training? As an MCT trainer, I can thoroughly recommend
TrainSignal. In particular, I like the way
that TrainSignal cover all learning methods, instructor lead, video and of course text
material. You can either take one module, for example Exchange 2007 or go for a combination of modules.
Learn more about Microsoft Exchange Server 2007 here
Exchange 2007 Server Virtualization - No!
As of June 2008 Exchange Server still does not support Virtualization.
While Windows Server 2008 has the wonderful Hyper-V, you cannot use it for
Exchange 2007 Server; this is the reason why, Microsoft Virtual Server only
supports 32-bit guests. You may know that Exchange 2007 server
REQUIRES 64-bit hardware.
Guy's advice is wait until Microsoft develops a 64-bit guest, before
implementing Exchange virtualization. Because email is the life-blood
of every organization, don't even think about trying a work-around. I
would not trust a 32-bit version of Exchange 2007, that version is only for
testing and installing schema bits. Why risk unsupported VMWare for
something as important as your email server?
Microsoft have decided on a structured approach and provide five roles for Exchange.
You have the flexibility to have multiple roles on the same server, or deploy a dedicated server for each role.
However, the Edge Server MUST be on a separate server in a separate workgroup,
there are also advantages in separating the Mailbox and Client Access roles.
Please write in if you see errors of any kind. Please report any factual mistakes, grammatical errors or broken links, I will be happy to not only to correct the fault, but also to give you credit.