Executive Summary:
Many organizations are using Microsoft's SharePoint platform as a crucial document management system and collaboration tool. Unfortunately, SharePoint provides no native item-level recovery of documents or list items stored within SharePoint. However, Microsoft System Center Data Protection Manager (DPM) 2007 gives administrators a rich set of recovery tools that offer advanced snapshot-based recovery of item-level SharePoint content as well as the entire SharePoint infrastructure. |
Microsoft SharePoint Products and Technologies have become a crucial
component of the infrastructure in many organizations, with the
platform serving as a mission-critical document repository and collaboration
tool. Unfortunately, the platform’s built-in backup and restore
capabilities have never really delivered the type of enterprise capabilities
that organizations have come to expect. Of particular note is the fact that
there’s no native way to provide for item-level recovery of documents or list items stored
within SharePoint. With the release of Microsoft System Center Data Protection Manager
(DPM) 2007, however, administrators have access to a rich set of recovery tools for Share-
Point, allowing for advanced snapshot-based recovery of SharePoint content from within a
simple but powerful interface. As with any new technology, there are tips and tricks involved
with DPM’s deployment and caveats that you need to take into account. Read on to learn
what it takes to deploy DPM into a Windows SharePoint Server (WSS) 3.0 or Microsoft Office
SharePoint Server (MOSS) 2007 environment, including best-practice architectures and
maintenance requirements of the application.
Introducing System Center Data Protection Manager 2007
In the past, organizations that required robust enterprise backup and restore capabilities
for SharePoint either purchased third-party software or constructed an elaborate process of
invoking command-line utilities such as Stsadm that performed site-collection-level backups.
Although many of these third-party products offer great functionality for SharePoint,
they can be expensive and cumbersome to use. Microsoft was on the line to produce a utility
that could easily manage and back up SharePoint on its own terms, allowing both for dayto-
day recovery of individual items within SharePoint and for full-scale disaster recovery of
the entire SharePoint infrastructure.
System Center DPM is Microsoft’s foray into the enterprise backup space. It’s the second
generation of a product that was designed to provide simple but powerful backup
capabilities for Microsoft infrastructures, including the Windows OS, Microsoft SQL Server,
Exchange Server, and SharePoint. Microsoft developed DPM to integrate directly with Windows’
Volume Shadow Copy Service (VSS), allowing the product to create snapshots of data
on a protected system as frequently as every 15 minutes. This means you could potentially configure DPM to recover a failed server to
a point in time no more than 15 minutes in
the past.
DPM offers two distinct benefits for
SharePoint administrators. The first is the
ability to take a VSS snapshot, back up the
SharePoint SQL databases, and provide upto-
the minute restoration capabilities. The
second benefit is DPM’s SharePoint-aware
item-level recovery capabilities, which
allow administrators to restore items from
the moment of the last recovery point. It’s
important to note that SharePoint content databases and SharePoint content, although
the most critical components to backup in a
SharePoint environment, don’t provide for
restores of the SharePoint indexes, Web part
binaries, or the IIS metabase on Web front
ends. These components should be backed
up using SharePoint’s XML-based backup
that is included in the product.
DPM also allows for other advanced
functionality such as Exchange database
and mailbox-level recovery capabilities,
bare-metal recovery of servers, and the
ability for end users to restore earlier file versions directly from protected file servers
simply by using Windows Explorer. In
addition, Microsoft makes DPM administration
robust and simple using either a
PowerShell console or the standard GUIbased
DPM Administrator console, which
Figure 1 shows. To keep managers happy,
the console also includes a series of built-in
reports, such as the ones shown in Figure 2.
These capabilities position DPM as a powerful
tool not only for SharePoint, but for any
Microsoft-focused organization.
Designing a SharePoint
DPM Solution
DPM performs backups from a central console
server. This server is directly attached
to any disk volumes or tape backup libraries
to which data will be backed up. DPM
performs both short-term (backup to disk)
and long-term (backup to tape) content protection,
and you can configure it to “expire”
content from the disk-based storage and
archive that content to tape.
I highly recommend DPM’s short-term
backup-to-disk capabilities. They allow an
organization to perform backups quickly,
without the need to spool to tape. To use this
option, you need to allocate a large chunk
of disk space to the DPM console. Typically,
the types of disks presented to DPM
are slower, cheaper disks such as 7200rpm
Serial ATA (SATA) drives on a SAN, or a
large DAS storage enclosure. The amount
of space required will vary depending on
how much data DPM is backing up, how
frequently it takes snapshots of the data, and
how often it performs Express Full Backups.
(DPM defines Express Full Backups as backups
that include all data from the target, but
transfer only changed files, reducing the
amount of time and bandwidth that the
backups take.) In addition, a SharePoint
item-level recovery backup is a separate
type of backup from a SharePoint SQL database
backup, so you might need to allocate
more disk space for this type of backup to
have the most flexibility with the SharePoint
restores.
To illustrate, let’s say you have 500GB of
data stored in SharePoint content databases.
Because the backup-to-disk volumes used
must be larger than the size of the data, you
would need approximately 700GB to 800GB
of space on the backup-to-disk volume just
for the SharePoint SQL database backups and the snapshots associated with them.
In addition, you need to set aside 600GB to
800GB of space for backups of SharePoint
items, as these types of backups are stored on
different volumes than the SQL backups are
stored. Total amount of space consumed to
back up 500GB of SharePoint content could
easily eclipse 1.5TB on the DPM console in
this scenario. Therefore, it’s important to
plan out the disk infrastructure required for
DPM’s backup-to-disk capabilities.
Incidentally, one common mistake
administrators make when allocating disk
space to DPM is that they create or format
volumes before presenting them to DPM
through the Management tab of the console.
However, DPM prefers unformatted,
raw disk space, because it creates a large
number of smaller volumes as part of its
provisioning process. You should simply
add raw disk space to the server and add the
disks to the console as needed.
Using the DPM System
Recovery Tool
It’s not immediately obvious how to back up
the DPM console, but it’s highly crucial to do
so to prevent the backup infrastructure from
collapsing. Microsoft provides a separate
tool, known as the DPM System Recovery
Tool (SRT), which Figure 3 shows, for backing
up the DPM console. The tool lets you
create a boot disk and provides bare-metal
recovery of any server it backs up. This
essentially lets you recreate the exact running state of any server, even if the original
server no longer exists.
There are a few key points that are important
to understand about the DPM SRT.
First, the tool is completely independent
from the standard DPM product. It installs
from separate media, uses its own agents,
and operates independently. Second, by
default, the SRT keeps all system backups
indefinitely, which could cause the server
to quickly run out of disk space. Be sure to
configure the server to keep only a specified
number of backups. Finally, remember
that without SRT, a DPM infrastructure has
a major Achilles heel: If the DPM console
goes down, all backup history and logs will
be lost, and recovering the data would be a
challenge.
Preparing Servers for Backup
There are several prerequisites you need to
satisfy before you install DPM and before
it can protect managed servers. First, the
DPM console must have access to its own
SQL Server database for storing DPM-specific
configuration and job information.
Best practice would be to use a local SQL
Server Express database on the DPM console
server, as storing the database on a
protected server could be catastrophic if that
server went down.
You should also install both Microsoft
IIS and Windows Deployment Services
(WDS) on the machine before you install the
DPM software. From experience, I can tell you
that if you forget to install
IIS and WDS in advance, DPM
installation will likely fail, particularly
if the server you are
installing DPM on is running
Windows Server 2003 SP2. You
must also install PowerShell 1.0
and the VSS patch referenced in
the Microsoft article “Availability
of a Volume Shadow Copy Service
(VSS) update rollup package
for Windows Server 2003
to resolve some VSS snapshot
issues,” at support.microsoft.com/kb/940349.
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