7. Server Administration
In
Exchange Server 2007, administrators were constantly reminded that to
take advantage of the improvements in high-availability technology,
there should only be one storage group per database. If having several
databases in a storage group complicated high-availability
scenarios and made single-database restores more complex, why bother
having them at all? Apparently Microsoft agreed: In Exchange Server
2010 and 2013, the concept of the storage group is no more.
Creating a New Database
Creating
a new mailbox database in Exchange Server 2013 is a straightforward
process. To create a new database from the EMS, a sample command is
shown here:
New-MailboxDatabase -Server E2013-1 -Name MDB2 -EdbFilePath D:\MDB2\MDB2.edb
-LogFolderPath D:\Logs\MDB2
To mount the newly created database, use the following command:
Mount-Database -Identity MDB2
Setting Limits on Databases
After
you create a database, you can customize the maximum storage limits and
deletion settings for mailboxes stored on that database. Although some
organizations consider limits of these kinds to be draconian in nature,
most understand that preventing users from storing unlimited amounts of
archaic data and the regular automatic purging of deleted items helps
to ensure a healthy and happy messaging system.
By
default, these settings apply to all user mailboxes stored on that
database. However, specific limits on individual mailboxes can be
configured to override these databasewide settings. This can be useful
when you want to set a limit for all users on a particular database,
but you have one user who needs more (or less) restrictive settings. To
configure these options, perform the following tasks:
1. Start the Exchange Administration Center.
2. In the left navigation control, click Servers.
3. Click the Databases tab.
4. Double-click the database that you want to configure.
5. Select the Limits tab.
6. Several limits are available to configure for the database. You can configure any of the following settings on the database:
• Storage limits—The
storage section limits enable you to configure restrictions on all
mailboxes located within that database. The available storage limits
options are as follows:
• Issue Warning At—1.9GB.
This is not a “hard” limit, but a warning threshold. When this limit
has been exceeded, the user will get a message warning them.
• Prohibit Send At—2
GB. This is a “hard” limit. When a mailbox exceeds this threshold, the
user is unable to send mail. This does not impact the user’s ability to
receive mail, ensuring the user does not miss any messages while
scurrying to clean up his or her mailbox.
• Prohibit Send and Receive At—2.3GB.
This is also a “hard” limit. When the mailbox exceeds this limit, the
user can no longer send or receive messages. Incoming mail destined for
this mailbox will be returned to the sender.
• Deletion settings—The
deletion settings dictate how deleted items and mailboxes in the
database will be dealt with. The available deletion settings options
are as follows:
• Keep Deleted Items for (Days)—By default, mailbox databases are configured to keep deleted items for 14 days.
Note
There is often some user confusion as to what
messages can be recovered using the Tools, Recover Deleted Items option
in Outlook. There are two types of deletion: hard deletion and soft
deletion. When users delete an item, it goes to the Deleted Items
folder and can be recovered simply by dragging and dropping it back
into the Inbox. If a user goes to the Deleted Items folder, and again
deletes the message, or if he or she selects Tools, Empty Deleted Items
Folder, the item has been hard deleted and can be recovered using the
Tools, Recover Deleted Items option. A user can also hard delete an
item by using Shift+Delete. This recovery can be accomplished if it is
initiated within the window set in the Keep Deleted Items for (Days)
section field. However, if a user enters the Recover Deleted Items
utility and selects to purge a message, or if the Keep Deleted Items
for (Days) period has expired, the item is hard deleted and cannot be
recovered without resorting to restore methods.
• Keep Deleted Mailboxes for (Days)—In
Exchange Server 2013, as it has been since Exchange Server 2003,
disabling or removing a mailbox does not mean that the mailbox is
permanently purged from the database immediately. The mailbox is
flagged for deletion and can no longer be accessed by users. After the
mailbox retention period controlled by this setting has been reached,
the mailbox is then purged from the system. This option is extremely
useful if a user deletion occurs that is the result of a mistake and
enables the administrator to create a new user object (if necessary)
and enable the deleted mailbox by connecting it to the user. By
default, this setting is set to 30 days. It can be configured anywhere
from 0 (immediate purge upon deletion) to 24,855 days. It is unlikely
you will ever need the upper limit (equivalent to a little more than 68
years), but this setting can be adjusted to meet your organization’s
needs. Unless disk space becomes an issue, it is recommended that you
do not disable the deleted mailbox retention feature.
• Don’t Permanently Delete Items Until the Database Has Been Backed Up—This
final setting is not enabled by default. By checking this option, you
instruct Exchange Server to not delete items or mailboxes, even after
the retention period has expired, until the database has been
successfully backed up. By selecting this option, you ensure that you
can recover critical items or mailboxes from backup media, even after
the purge has been completed.