Get the Message
Straight talk on meshing your enterprise e-mail systems.
- By Bill Heldman
- July 01, 2003
In my younger days, I was hired to migrate 800 or so users off of Banyan
Vines to Windows NT 4.0. Additionally, I was tasked with setting up an
Exchange 4.0 server with the same goal of taking users from Banyan’s
e-mail system to Exchange. I successfully set up the e-mail server and
we utilized a special but expensive third-party product to migrate users
(a few at a time) off of Vines to Exchange. In the interim—for those
that weren’t yet converted—our “connector” to
the two systems was simple SMTP e-mail through the Internet.
But what if you want to convert lots of users off of different disparate
systems? Wouldn’t it be easier if Microsoft provided a way so that
you could simply connect up to the foreign system and get e-mail going
between the two? Good news—they have!
If you work in a large environment, one that has a lot of geographically
or functionally dispersed areas, you might have a two or three different
e-mail server technologies to deal with. This can be a bugaboo for you
in an Exchange 2000 migration, never mind the potential hassles that you
have to go through with an Exchange 5.5 to E2K upgrade.
In the Exchange world it’s important to remember that you have
two separate pieces of information you have to be concerned about: the
actual mailbox data as well as the calendar data—the so-called “free
and busy times.” Other enterprise e-mail systems may not segment
the notion of mail versus schedule as does Exchange, but they may include
scheduling capabilities for e-mail users. So it’s important to understand
not only how you’re going to get your users to access their inboxes,
but also how they’ll share free/busy times, if at all. The sharing
of free/busy times allows users to see one another’s schedules and
to create appointments accordingly.
Connecting Exchange 5.5 and Groupwise
The primary idea behind connecting two or more e-mail services
together is so that all users share the same primary list of users in
the corporate e-mail address book. In Exchange the corporate book is called
the Global Address List (GAL) and represents the list of users, groups
(called "distribution lists" in Exchange 5.5) and non-Exchange
recipients (called "custom recipients"). The idea is to allow
your disparate e-mail systems to co-exist, so that directory information
can be shared. This co-existence might be short-term as you migrate users
off of the old e-mail system to the new, or long-term. For example, suppose
that you have an autonomous division in your company that exclusively
utilizes Netware for its server OS and Groupwise for its e-mail server
product, but the rest of the company uses Exchange 5.5 Server. In this
case you may need a way to have the e-mail systems coexist permanently.
Optionally, if a new CIO comes on board and says “Everyone will
use Exchange Server” then you’ll be faced with a Groupwise
to Exchange migration.
In the case of Exchange 5.5 and Groupwise 4.x or 5.x (not 6.x) you have
several options available to you after Exchange 5.5 with Service Pack
- Microsoft Exchange Connector for Groupwise—Allows
you to connect with a Groupwise server; supports message transfer and
- Microsoft Exchange Server Migration Wizard—Allows
you to move users off of Groupwise and onto Exchange.
- Microsoft Exchange Calendar Connector—Provides near-real-time
access to free/busy calendar information from each system.
By directory synchronization (dirsync) we mean the information about
the users in each system. Exchange first updates Groupwise by converting
its entries into Groupwise format. It then retrieves the Groupwise directory
information and populates it in Exchange. Thus the two systems are synchronized
with one another. The Exchange connector on the Exchange server uses the
Groupwise API Gateway on the Groupwise server to accomplish this goal.
Here’s the rub: This is a scheduled dirsync and doesn’t happen
synchronously (i.e. all the time). You must set a schedule whereby dirsync
happens. There is quite a bit of granularity available with this schedule,
so don’t fret that you’ll be limited to a once a week dirsync
between the two servers.
You have some controls over how you implement this Exchange 5.5/Groupwise
directory synchronization process:
- You can create containers that house specific Exchange recipients
and export only those containers to Groupwise.
- You can set a trust level so that certain Exchange recipients (such
as the Exchange admin account, for example) are not synchronized.
- You can opt to not synchronize recipients such as custom recipients.
- You can decide whether to import/export distribution lists (DLs).
(In Groupwise 4.x, DLs were called groups whereas in Groupwise 5.x they’re
called Groupwise Distribution Lists and appear in Exchange 5.5 as custom
- Schema attributes are mapped accordingly. For example, the field
company in Groupwise will match to the field company in Exchange 5.5.
When a user composes an e-mail and sends it to a Groupwise user, the
Exchange connector sends it to the Groupwise API Gateway which in turn
converts the message into the normal Groupwise message format. The Groupwise
Mail Transfer Agent (MTA) then delivers it to the Groupwise recipient.
The opposite is true for a Groupwise recipient sending an email to an
Exchange 5.5 user.
The Exchange Calendar Connector uses a free/busy public folder to post
the free/busy information of the Groupwise server, according to the dirsync
schedule set up by the administrator. If an Exchange user requests free/busy
information from a Groupwise user, the public folder is first queried.
If no information is found, a request for that information is sent by
the Exchange Connector for Groupwise to the Groupwise system.
You use the Exchange Migration Wizard when you want to move users from
the Groupwise server to the Exchange 5.5 server. Depending on the size
of the organization, you can opt to perform a one-step migration that
moves everyone or you can perform two-step migrations in which you move
small groups at a time.
Connecting Between Exchange 2000 and Groupwise
The process differs only slightly with Exchange 2000 in that Microsoft
provides another utility, called the Active Directory Account Cleanup
Wizard, to make it easier to copy Groupwise information into the Exchange
system, either through a migration or a connector effort, that is mapped
to the appropriate Active Directory account. All utilities are available
on the Exchange 2000 CD (with no service packs), however Exchange 2000
with SP1 is required for free/busy information.
Before we move on, here are some problems to keep in mind for Exchange
5.5 and Exchange 2000 servers connected with Groupwise 4.x or 5.x:
- Recurring appointments cannot be sent from Exchange to Groupwise.
The user receiving the appointment sees a note at the top of the appointment
that it is recurring and it is left up to him to manually key in the
- You cannot query free/busy information for distribution lists on
the Groupwise server.
- The Exchange Connector for Groupwise does not support Exchange messages
that are signed and encrypted.
Connecting Exchange and Lotus Notes/Domino
But suppose instead that you have a complicated groupware implementation
in which you not only have a messaging system, but you’ve got applications
developed around that system that you want to connect to with Exchange.
Now you’ve got your hands more full because you have to concentrate
on the various documents that were created in the Notes/Domino system
and somehow link them so that they’re delivered to the Exchange
user in a meaningful way.
Exchange 5.5 SP4 provides a Lotus Notes Connector that does exactly
that. It utilizes a Notes feature called DocLink, to allow Exchange users
to receive via .RTF or OLE object attachments (and from Domino, hyperlink
attachments) in order to interact with the Notes system. Depending on
how the Exchange administrator has configured the Lotus Notes Connector,
the user will receive one of three attachments:
- A rich-text (.RTF) file that the user can open via any RTF-compatible
- An OLE object to click on. For this to work, users must have the
Notes 4.52 client application installed on their desktop. When the user
launches the OLE object, the Notes application is launched and the user
sees the Notes document.
- In the case of Domino server, which has an embedded HTTP server mechanism,
the user can receive a hyperlink, pointing back to the Domino server.
The Notes connector allows for either a complete dirsync, or a dirsync
of the deltas (only the changes) that have occurred to either system.
Also, Notes groups and Exchange DLs are maintained. The connector does
not maintain some Notes elements: mood stamps, bullets, numbering, tables,
collapsible sections and encryption.
There are four Notes implementation scenarios:
- Departmental connection—Single Exchange site to single
- Downstream sites/domains—Multiple Exchange sites to
multiple Notes domains
- Shared Internet-Access—Utilizing Exchange’s
Internet Mail Server (IMS) technology so that Notes users can make use
of its functionality (along with the regular Notes connector)
- Message-switch—This very exotic implementation scenario
utilizes the Notes connector and the IMS for Notes clients, as well
as the Exchange connector for an IBM e-mail product called OfficeVision.
This scenario is dubbed message-switch because the message can traverse
one of three systems.
In the Exchange 2000 environment, you use not only the Connector for
Lotus notes but you’re given more robust tools to facilitate a better
- Microsoft Exchange Analyzer for Lotus Notes—Allows
the administrator to examine what Notes applications are running in
- Microsoft Exchange Application Converter for Lotus Notes—Allows
administrators to connect to the Notes applications and convert them
for use by Microsoft Outlook.
For the world’s dominant e-mail systems, there has probably been
a connector written for Exchange so that you can connect to the system
and, if so inclined, allow migrations off of it. I don’t pretend
to underplay the many challenges with installing, configuring and getting
the connectors running. (See www.microsoft.com/exchange
for more information on connectors.) Nonetheless, the technology is
there for you if you want your disparate e-mail systems to coexist and,
thus, allow users on any system to happily trade e-mail one with another.