October 29, 2008

Archiving Email: Is It Being Done The Right Way?

For those of you who have a growing repository of email, you'll find that you need to archive it. Using Microsoft Outlook, in particular you need to archive the email, especially older email so that it takes up less space on the local computer and the server.

When archiving you need to ensure the emails can be readily available to the end users should they need it. It's also important to archive the email for legal reasons.

GFI provides a variety of security and messaging software and shared with me that one thing to be careful of when archiving email is "stubbing".

Stubbing involves moving emails from the users’ mailboxes to a new location, while replacing the original email in the user mailbox with a small message “stubs” pointing to the new location of the email. However, several problems may occur when an email archiving solution makes use of stubbing.

First, the reduced size of a message does not really avoid the problems that stubbing was meant to prevent, which is solving the storage and performance concerns with email archiving. Over time, an archiving solution working on hundreds of mailboxes will create thousands of small stub messages. Each of these stub messages may be between 2 and 15 kilobytes and still amount to a performance hit since item counts is the primary performance driver for the Exchange store rather than aggregate size.

Second, email archiving solutions that make use of stubbing typically enumerate all emails in a mailbox and replaces the emails with a stub. Enumeration of emails is a processor intensive activity especially when this is done on each mailbox on the Exchange server. Processor intensive operations can have a negative impact on the performance of Microsoft Exchange especially when it is under load serving a large number of Outlook users.

Third, the ability to search archived emails is another important consideration and functionality that makes an archiving solution usable. In solutions that make use of stubbing, the content of the original email is not available for searching. This means that users making use of Outlook’s search functionality to find old archived emails will not get any useful results. Therefore typical archiving solutions that make use of stubbing render the built-in Outlook searching functionality useless for searching old emails.

Finally, stubbing also changes the way that Microsoft Exchange normally works because third party code has to be installed on the Exchange server itself to enable stubbing functionality. Experienced administrators know that the introduction of any new component to the system can easily affect the availability and reliability of the servers that they administer. This is especially of concern when the new component has to directly affect the way that Microsoft Exchange functions. System administrators loathe the idea of installing software on their production servers simply to evaluate it. As a result, many may have to create a test server which impinges on the administrators’ already valuable time. An evaluation of such an archiving solution therefore will not reflect the load of the live Exchange server.

Listen to a webcast about email archiving here.

tags: archive , email , stubbing | 0 comments