The sheer glut of email presents serious storage issues and performance problems for an email server. Email is regularly indexed and archived out of the email server to a secondary storage system for long-term retention. If an email or thread is needed later -- often in response to litigation -- the email archive's contents can be searched to locate relevant data.
Email's popularity has had a profound impact on archiving. But not all email archiving tools are created equal. An archiving tool must interface with your email or database system, yet impose few performance penalties against the applications using the email archive. Your company should have retention rules planned ahead of time, and you should consider the need for index/search capabilities to address e-discovery demands. Since the volume of email is constantly growing, an email archiving tool must scale well.
All these factors come into play for anyone purchasing an email archiving tool. Each tool out there has its own strengths and focus. Tools like C2C's Archive One are intended for Microsoft Exchange, while EMC Corp.'s EmailXtender supports Domino and Sendmail servers as well as Exchange.
A good place to start is by reviewing the issues involved in a
Compatibility with your current software. Email archiving tools should interface closely with your existing email or database system. The issue lies in the number of platforms that are compatible and the level of compatibility for each platform. Smaller organizations with no plans to change their email platform might be better off with a narrowly focused email archiving product; large organizations that use more then one email/database system will benefit from a tool with cross-platform compatibility. As an example, MailMeter Archive from Waterford Technologies Inc. supports Microsoft Exchange, Lotus Domino and Ipswitch IMail along with SQL Server and Oracle. By comparison, Mimosa NearPoint for Microsoft Exchange Server is primarily intended for recent versions of Exchange.
Performance and scalability. Email archiving tools will have an effect on their related applications. Any email archiving tool for Exchange will impose a performance penalty on Exchange (and users). Archive performance may decline as the archive platform scales with more users, more email boxes and larger storage limits for each user. This may not be an issue for businesses with a small number of users, but may pose a serious problem for large or quickly growing businesses. Email archive administrators must gauge the performance impact and scalability of an archive tool. Up-front lab testing should uncover any unexpected performance or scaling problems.
Use existing retention and deletion policies. All email archiving tools can be configured to accommodate data retention and deletion, but selecting the best retention rules on the fly is nearly impossible. It's much easier to map an existing retention policy into an archive tool than to create new rules as needed. A company's current document retention policy is usually a good starting point. If no such retention policies exist, create them by conferring with principal stakeholders in the organization, as well as legal counsel versed in compliance and discovery issues.
Archives need adequate storage. Archiving tools will demand storage on another server or storage array. Nearline SATA-type storage will offer adequate performance, but the actual amount of archival storage will depend on the size and number of email messages. Vendors, such as Mimosa, suggest that email archive storage may demand up to three times the size of the production Exchange server. And if there's a ton of attachments, additional storage resources might be required.
Storage requirements will also vary with corporate retention policies. Long retention policies and "litigation hold" features will save more email, further swelling storage requirements. Most archiving products include data reduction technologies that can reduce storage demands such as compression or data deduplication. An email archiving vendor can offer a better estimate once they're familiar with your email server environment and compliance needs.
Evaluate specialized product strengths and features. Virtually all email archiving tools are adept at data storage and retrieval, so you'll want one whose features are suited for your specific needs. An organization with litigation worries might select an email archiving tool with extensive metadata creation and indexing or strong e-discovery search capabilities. If business continuance or disaster recovery are priorities, you might want an archiving tool with remote replication features. If minimal storage requirements are important, look for a tool with data deduplication.
How suitable are data deduplication technologies? Deduplication has become a cornerstone of archival storage, but it is not always accepted by litigators that demand complete file content. When implementing an email (or any other) archiving system to support litigation, be sure that deduplication use is acceptable given your specific compliance needs or legal exposures. Archiving systems that forego deduplication will be far costlier to operate.
What about software maintenance and licensing fees? The cost of software maintenance contracts and annual licensing fees can significantly boost the cost of an email archive product and should always be factored into total cost of ownership (TCO) estimates prior to a purchase. For example, GFI's MailArchiver for Exchange carries standard pricing down to $7.88 per mailbox ($7,880 for a 1,000-mailbox license). However, this price only includes three months of upgrades and maintenance; an annual service agreement would cost 20% of the purchase price.
This chapter includes product specifications for the following email archiving products:
This was first published in February 2008