Microsoft Exchange Server 2010 : Getting Started with Email Archiving - Enabling Archiving (part 2) - Using Exchange 2010 Discovery, Offline Access

3. Using Exchange 2010 Discovery

To use Exchange Server 2010 Discovery, a user should be added to the Discovery Management role group. By default, this group does not have any members. Administrators who have the Organizational Management role are restricted from doing any Discovery searches without being added to the Discovery Management role group. Discovery is a powerful feature that allows anyone with the appropriate permissions to have potential access to all the email records stored in your entire organization. Therefore, it is critical to control and monitor who gets access to the Discovery Management role and keep a close eye on the Discovery actions.

You can use PowerShell to add a user to the Discovery Management role group. To add, for instance, User John Doe, the cmdlet looks like this:

Add-RoleGroupMember "Discovery Management" -User Jdoe

Figure 2. Accessing a personal archive with Outlook 2010

Figure 3. Accessing a personal archive with OWA

After you have gotten permission, you can open the Discovery Manager console by going to https://servername.local.com/ecp and logging in with your credentials (see Figure 4).

Once logged in, you can select what you want to search. You have the option to search on Mailboxes, Groups, and External Contacts. In Figure 5, we selected Mailboxes and clicked the Search option.

On the Search page, select the keywords, message types, to and from addresses, date range, and mailboxes you want to search on. Before clicking Save, be sure you select a storage location (discovery mailbox) for the search to be saved to as well as a unique search name. It is important to understand exactly what a discovery mailbox is. It should be a special resource mailbox that has been configured with large quotas (50 GB), permissioned so that only discovery role administrators can open it, with email delivery disabled.

Figure 4. Exchange 2010 Discovery Manager Console

3.1. Viewing the Search Results

Once the search is completed, the results are copied to the target mailbox that you specified in the search configuration. The Discovery application will create a new folder in the mailbox that has the same name you gave to the search, and a subfolder will be created below that for each mailbox that had information that matches the search query.

4. Offline Access

Most users have Outlook configured to synchronize their mailbox with Exchange using an offline folder, or OST, file. This gives users an offline cache so that they can still read their email when they are not connected to the network. The personal archive is not integrated with the OST file, which means that when data has been moved from a user's mailbox to their archive, the data will not be in the offline cache. If the user requires access to this data, she has two options: get access through OWA or move the data back to her live mailbox. Most people when they are traveling or flying on an airplane are not looking at old email but most likely processing some of the more recent information they have received.

Figure 5. Selecting Mailboxes in the Discovery Manager Console

5. Requirements and Factors to Consider

There are several important factors to consider when you deploy Exchange 2010 archiving in your organization.

5.1. Licensing

The archiving functionality in Exchange 2010 is marketed as a way that organizations can get archiving for free without purchasing an expensive third-party business archive solution. But as with lots of marketing, you have to lift up the curtains a bit to get the correct answer.

As a starter, the archiving functionality requires an Enterprise client access license also known as eCAL, which adds some cost on top of the regular license cost of Exchange Server. Also, you need at least Outlook 2010. Of course, you can use Outlook Web Access for lots of the functionality, but it's smart to deploy Exchange 2010 in combination with Outlook 2010 since the archiving functionality in Exchange 2010 is only available with the RTM release with Outlook 2010. This isn't in line with the "free" marketing theme, but it is embedded within the product.

5.2. Server Storage

When it comes to archiving software, proper storage planning is important. With Exchange 2010 there are a few additional "curveballs" you have to work with. Some architectural changes were implemented in the Exchange database structure with Exchange 2010. Single-instance storage (SIS) has been removed in favor of better performance and reduced input/output per second (IOPS) requirements. Single-instance storage refers to storing a single copy of a message or item once, even though it is stored in multiple locations. On average, the SIS savings were about 20 percent. But for an Exchange database that is upgraded from Exchange 2007 to Exchange 2010, this increase has largely been mitigated by the page compression features that were added in the Extensible Storage Engine (ESE) functionality.

Additionally, when you bring in PST files with Exchange 2010, you need to ensure that the additional capacity is available. The problem gets more interesting when you start deploying database availability groups (DAGs) and replicate data. You will not only replicate the primary mailbox but also the archived data in the personal archive. This could mean that your storage requirements grow exponentially. There is a reason why Microsoft put the personal archive in the same database as the primary mailbox it belongs to: Microsoft spent a lot of time making Serial Advanced Technology Attachment (SATA) storage a viable option for Exchange 2010 for both performance and capacity. If you decide to go with SATA, there is no reason to split the personal archive and primary mailbox onto separate databases because you are already on the cheapest disks out there. In addition, keep in mind that disk capacity is continuing to increase while performance isn't; this means that if you continue to split the data onto different drives, you are not maximizing the efficiency of the drives (either capacity or performance). The personal archive is attached to the primary mailbox and can't be split up on two separate databases.

If your organization is going to use the Discovery functionality extensively, be prepared for the additional storage requirements as well. This is, of course, because of the removal of SIS; however, the added page compression that was included in Exchange 2010 does provide some mitigation against this. A rapid increase in storage needs could occur when someone is going to create a large search result set that is copied to the Discovery mailbox. When you quickly export those results and provide them to the legal team, this might only be a short-term problem.

5.3. Client Requirements