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Optimize Exchange storage

E-mail archive solutions are highly touted for their compliance benefits, but they also can serve to optimize Exchange storage.

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With e-mail archiving, you can optimize Exchange storage, improve Exchange efficiency and better manage total Exchange storage costs. Your Exchange server will run faster and be easier to manage, because it won't be burdened with attachments and old deleted messages. Daily Exchange processes such as backup, indexing and defragmentation will also run faster and more effectively, and users will be able to store more e-mail and be less reliant on PST files.

Offload attachments to nearline storage with e-mail archival

Depending on the size of your Exchange server, your backups may already be exceeding your backup window. To avoid sacrificing service quality, you may need to find an alternative (and more costly) means to backup faster, or you need to find a way to reduce the amount of Exchange data. Typical e-mail archiving products have a feature that moves attachments from Exchange to nearline storage and replaces them with a small file "stub." Simply by removing attachments in this way, it is possible to reduce Exchange storage by over 50%.

Reduce mailbox quotas

Reducing total storage with an e-mail archiving product immediately benefits your Exchange backups, which will run faster and consume less tape media. Faster backups also mean faster recoveries should your Exchange server ever fail. Because users are consuming less space per mailbox, they can afford to store more e-mail and hold old e-mail for a longer period of time. You may wish to reduce mailbox quotas due to the increased storage utilization. Storage reduction also allows you to support more users per Exchange server and further reduce infrastructure costs.

Reduce Deleted Item Folder size

There are other benefits to reducing Exchange storage, too. Take, for example, the Deleted Item setting for Exchange. An e-mail archive serves the purpose of archiving all e-mail and allows for individual message recovery, so you can reduce this from its current setting (days) to zero.

Exchange online defragmentation is a process that runs daily to recover "white space." After your Exchange Store is reduced in size, another benefit you'd discover is that your online defragmentation program runs more effectively and you will be less in need of offline defragmentation. Exchange indexing, which runs continuously, will also run faster with a smaller Exchange Message Store.

Restrict Personal Store use

Are Personal Store (.pst) files used in your organization to offload crowded mailboxes? If so, after attachments are removed, you will find that users have plenty of room to store old e-mail and PST files use can be reduced or eliminated all together. PST files are useful for offline e-mail access and their use should be restricted for this purpose only. Otherwise, there is too much risk of lost e-mail and it is too difficult to control valuable company intellectual property when it exists on every desktop.

Reduce Journaling storage capacity

Are you using native Exchange Journaling to retain 100% copy of e-mail? A common practice is to use Journaling for selected mailboxes to capture every message for compliance. The major drawback of native Exchange Journaling is the space it consumes on Exchange. A typical e-mail archive application is able to read this Journal folder and truncate the folder after copying the messages to the archive. In this way, you can manage selected mailboxes for compliance and not consume valuable space on Exchange.

Checklist to optimize Exchange

  1. Offload attachments to nearline storage with e-mail archival
  2. Reduce mailbox quotas
  3. Reduce Deleted Item Folder size
  4. Restrict Personal Store (.pst) use
  5. Reduce Journaling storage capacity

About the author: Bob Spurzem is Senior Product Marketing Manager at Mimosa Systems, a software development company in Santa Clara, Calif. He can be reached at

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