Archiving alone won't shrink Exchange

10 Aug 2006 | SearchStorage.com

E-MAIL ARCHIVING, a sizzling hot segment of the storage market, is winning converts every day. But many Exchange admins are finding one of the most touted benefits of these products--slimmed down Exchange mail stores--somewhat elusive.

The e-mail archiving vendors aren't overstating the prowess of their applications, but they often fail to mention a big step in the process of regaining disk space from bloated Exchange databases. "Every single one of them is promising a smaller, faster, leaner, meaner database that you back up faster and restore faster--if you need to do it-- and it's just not true," says Troy Werelius, CEO of Lucid8, a provider of Exchange utilities. "They do the prep work for it."

Tim Tiches, director of product management for CA's Message Manager (formerly iLumin Assentor), concurs. "We will stub messages to reduce the footprint, in theory, on the Exchange server," says Tiches, "but the actual space isn't recovered until it's compacted."

After an archiver moves messages and attachments from the database to the archive destination, the Exchange database doesn't actually shrink. The items that were removed no longer show up in mailboxes or on calendars, but the disk space they formerly occupied is still part of the Exchange database. Those newly vacated areas of the database are referred to as "white space" and may be filled with new messages. "It can get overwritten if everything's lined up perfectly," says Werelius, "but if you talk to companies that really run Exchange--whether it's 5.5 or 2003--they'll tell you, 'No, my database still grows.'"

To actually reclaim the space, an admin has to run a utility like Microsoft's Eseutil or Lucid8's GOexchange to defrag and compact the database. But even using a product like GOexchange, which simplifies the process, involves taking the database offline (and e-mail out of service) for hours at a time.

"One of the reasons I purchased GOexchange was to facilitate that issue," says Bob DuBois, director of IT at Devine, Millimet & Branch, a Manchester, NH, law firm, who also uses Zantaz Enterprise Archive Solution to archive the firm's e-mail. "I wanted some automated tool so that I didn't have to go command line all the time."

Besides shutting down mail service, bringing down Exchange to compact the database is an uncertain proposition because an admin won't know exactly how long it will take. "You can't really predict," says Devine, Millimet & Branch's DuBois. "You can only guess-timate."

There seems to be at least a glimmer of light at the end of the tunnel as Microsoft is reportedly working on a solution to the problem. "I had a few discussions with the Microsoft folks," says CA's Tiches. "[They say] they're going to solve that in [Exchange] 2007." Lucid8's Werelius isn't as optimistic about Microsoft's efforts because he thinks those improvements are linked to Microsoft replacing the Jet database at the heart of Exchange's mail store. "Microsoft's most recent statement is that their goal is to be off of it by 2012," notes Werelius.

The Jet database engine was introduced by Microsoft in 1992, and it's the underlying database manager for such popular apps as Microsoft Access and Excel. The technology is somewhat long in the tooth, and is considered the root of some of the problems associated with Exchange data stores. Werelius says one such issue is the inadequacy of Microsoft's online compaction, which makes regaining disk space an awkward process.

"If you push [Microsoft] to that point, they tell you that's true," says Werelius. "That's one of the reasons they're going to try to move off the Jet database."

Tiches thinks they could address the problem, but it would require loading his firm's software on the Exchange server--something they're loathe to do because their customers don't want to complicate their Exchange environments. "I think we could solve that problem, but I think it would create other problems," says Tiches. "Our expectation and hope is that Microsoft will find a way to solve it themselves with some of their 2007 technology."

With doubts that a fix from Microsoft is forthcoming, Lucid8 is working on a version of GOexchange that compacts the database without having to take it offline. "We're working on an online version; we have it working in our lab," says Werelius. "But you probably won't see it out in the world until late this year or early next year."

Letting e-mail users continue to work with Exchange while its database undergoes maintenance would be a boon to Exchange admins and e-mail archiver vendors, too. "If they do that, I'd be loving life," says DuBois.

--Rich Castagna

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