Enterprise Software

Decision Support: Exchange directory sync problem is compounded when organizations combine

Tells the story of the problems encountered by TechRepublic and Gartner IT professionals when they decided to synchronize their Exchange databases

Businesses combine strengths in a variety of ways these days, through acquisitions and other cooperative arrangements, and when they do they often want to take advantage of each other’s resources.

This happened recently here at TechRepublic when Gartner, a business technology advisor based in Stamford, CT, acquired a majority interest of TechRepublic.

Both companies are running Microsoft Exchange, and because the Exchange directory can hold a great deal of organizational information, there was a desire to synchronize the directories of each company with the other.

But here's the rub: How can these two directories be synchronized and yet remain totally independent of each other? The two companies didn’t want to merge their mail systems, even if it would be transparent to users.

Easier said than done
Although synchronizing two directories using the same mail server program might appear to be a simple task, this isn’t the case with Exchange.

According to James Browning, research director for the Small, Medium Enterprise Research Group at Gartner, the Exchange program sees the directory from an attribute definition of an “organization.”

With the organization as the top-level definer, it can be subdivided by servers and sites. If both companies were defined as the same organization, there would be no problem combining the directories.

“But we are under different organizational names [Gartner and TechRepublic], and Microsoft didn’t plan very well for this. Interorganizational synchronization is a very complicated process within Microsoft Exchange,” Browning said. “That is where the problem lies.”

There’s the right way, and there’s . . .
Within the Exchange program are two tools that could help solve the synchronization problem, but because neither is supported by Microsoft, most companies are reluctant to deal with their complexity, Browning said.

“Microsoft Consulting does this every once in a while,” he said. “They create a specialized tool and then word gets out that this tool exists. Microsoft will sometimes integrate it into Exchange and other times, it is just left dangling as an unsupported tool.”

Dominic Bosco, TechRepublic’s senior systems administrator, said his first choice was to use one of those tools, called the InterOrg Synchronization Tool (IST), because it looked like the quickest way to implement an automated directory synchronization.

The IST is an Exchange add-on contained in the BackOffice 4.5 Resource Kit that's intended to synchronize directories between different Exchange organizations.

Along with being the most direct way of synchronizing the directories, Bosco said it allows for automating the task, and it uses SMTP, “so the synchronization uses Internet connectivity rather than expensive WAN links.”

Other options considered
Bosco and Browning also evaluated these options for synchronizing the two directories:
  • The other tool in Exchange, called Linkage
  • A synchronization method called lightweight directory access protocol (LDAP)
  • A “home-grown” solution based on Exchange’s export/import function
  • Outsourcing a portion or all of the mail server functions

Linkage and LDAP
The complexity of the first option is discouraging, Browning said. The Linkage tool came from a company called Linkage Software that Microsoft acquired a few years ago. Linkage Software had built its program around Exchange, and Microsoft incorporated some of its code into Exchange 5 and 2000 after it bought the smaller company.

“When you look at this from the perspective of the small or good-sized enterprise, this is another hard-to-manage piece that isn’t very attractive,” Browning added.

As for the second option, Bosco said he wouldn’t attempt LDAP without the support of someone with more knowledge and experience with the protocol.

Growing your own: A common IT solution
Exchange does offer the option to export and import data out of and into its directory, both IT professionals said.

“That’s a little tedious, a manual process, but that’s probably the cheapest way to do it,” Browning said. “I think most small enterprises that need to do this are probably using some sort of homegrown process like this.”

Bosco agreed that the manual approach was workable. “We can do a synchronization via good old text-based file exports and imports where I FTP that over to Gartner, and they have a batch process that picks it up and imports it,” he said. “[One] problem with that is you have to write a script where the data gets massaged—you have to export it and massage it to get it ready for them to import.”

Another challenge is that you're taking a snapshot of the directory.

“The problem with that is that if we do this on a weekly schedule, you don’t have access to changes we may make tomorrow,” Bosco said.

Outsource the solution
“In some areas where small businesses can’t afford the skills and budget to bring in the hardware and software and install some new technology, they look to service providers to [handle mail server functions] for them,” Browning said.

Some of the most common e-mail service providers include:

“Outsourcing has its advantages and disadvantages,” Browning said. “Whether it is directory synchronization or doing the whole task, that is something that needs to be examined at a high level.”

While you gain the simplicity of having someone else deal with the details in outsourcing, he said, you also lose control of how your directory functions.

The analyst suggests you sit down and decide what your real business requirements are and then pick the pieces that will get the job done. Do you only need to exchange e-mail? Do you need to do scheduling? The complexity of your requirements may lead to the strategy you need to follow to resolve the issue.

The big finish
At TechRepublic, Bosco and his Gartner IT cohorts finally were able get the Exchange IST to work on both the “Master” and “Requestor” ends, but it was no simple task.

“It was a matter of [deciphering] some poorly written documentation,” Bosco said. “You really have to understand how Exchange works to understand the documentation for the tool.”

Once the IT professionals at each end of the synchronization understood what the documentation was trying to tell them, it was a matter of configuring each mail server to expect and process the data appropriately.
Do you have an Exchange horror story to tell? Have you had to synchronize two disparate, or even similar, e-mail server directories? Post a comment below or send us anote telling us what you did.

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