1. Defining Your Archiving Requirements
The first step in planning for archiving in a Lync Server 2010
deployment is determining the requirements. Start by answering the
following questions about the environment:
• Which sites and users in the organization require archiving support?
• Will archiving be needed for internal communications, external communications, or both?
• Should archiving include IM, conferencing, or both?
• Is archiving critical enough that IMs and conferences shouldn’t be allowed to occur if archiving is unavailable?
• How long should archived materials be retained?
Answering these questions enables you to determine how the archiving policies should be created.
Archiving policies are used by Lync Server 2010 to make decisions
around what content should be archived, for whom it should be archived,
and for how long it should remain in the archive. When planning the
archiving policies, keep in mind that there are three types of
archiving policies, each with a different intended purpose:
• Global archiving policy—This
default policy applies to all users and sites in the deployment. The
available options include the archiving of internal communications,
external communications, or both. This policy cannot be deleted.
• Site archiving policy—This
policy enables or disables archiving for a specific site within Lync
Server 2010. Typically when deploying site archiving policies, disable
archiving in the global policy; otherwise, all sites effectively
process the global policy.
• User archiving policy—This
policy enables or disables archiving for a specific user within Lync
Server 2010, regardless of the sites in which the user is associated.
This type of policy is typically used in environments where only a
specific class of users requires archiving.
In each of the archiving policies, you can choose to archive IM
only, conferences only, or both. If both site and user policies are
implemented, user policies will override site policies.
The other decision that must be made when planning archiving
policies is whether to implement critical mode archiving. Critical mode
enforces a behavior such that if archiving isn’t
available, the system will prevent IM and conferencing from occurring.
Critical mode is configured in the Archiving Configuration tab within
the Lync Server 2010 Control Panel.
Finally, when planning the archiving requirements, determine how
long archived data should remain in the archive. By default, purging
archives is not enabled. The purge period can be set to as low as 1 day
or as high as 2,562 days (just over 7 years). You can also choose to
only purge exported archiving data. This option purges records that
have been exported and marked as safe to delete by the session export
tool.
2. Planning Your Archiving Topology
In Lync Server 2010, archiving consists of three components:
• Archiving agents—These
agents are automatically installed on every Front End pool and Standard
Edition server. The agent captures messages for archiving and sends
them to the destination queue on the Archiving Server. Although the
agent is always present, it only acts when an archiving policy is
enabled.
• Archiving Server—This
is the server role that reads the messages sent by the archiving agents
and writes these messages to the Archiving back end database.
• Archiving Server back end database—This
is the SQL server that stores the archived messages. This database can
be collocated on the same computer as the Archiving Server or can be on
a dedicated system if scalability is an issue.
There are three typical topologies for deploying archiving, as shown in Figure 1.
Figure 1 Typical Topologies for Deploying Archiving
The Archiving Server can be collocated with a Monitoring Server,
with a SQL store of a Front End pool, or with a file store of a Front
End pool. The Archiving database can also be collocated on the same
computer that runs Archiving Server or the computer that runs
Monitoring Server.
Regardless of which topology is chosen, there
are some common requirements that should be planned. In addition to the
normal requirements for Lync Server 2010 in terms of supported versions
of Windows, also ensure that a valid version of SQL is used. The
Archiving Server is compatible with the following versions of SQL:
• Microsoft SQL Server 2008 SP1 Enterprise Edition
• Microsoft SQL Server 2008 SP1 Standard Edition (x64)
• Microsoft SQL Server 2005 SP3 Enterprise Edition
• Microsoft SQL Server 2005 SP3 Standard Edition (x64)
• Microsoft SQL Server 2008 Express (x64) only when used on Standard Edition Lync Server 2010
In addition, the Archiving Server needs Message Queuing installed
with Active Directory Integration enabled. This requirement is
applicable to any Front End or Standard Edition Lync Server 2010
systems that host users who have archiving enabled.
From a scaling perspective, support as many as 500,000 users on a
single dedicated Archiving Server. For environments with fewer than
500,000 users and multiple Front End pools, deploy a centralized
Archiving Server unless unusual network constraints exist. It is also
recommended to validate a topology with the legal department to ensure
that there are no issues with holding archived communications from one
country to another. Some localized privacy laws might affect the
capability to deploy a centralized Archiving Server.
To optimize performance on the Archiving Server, plan to deploy three physical disk groups to hold the following information:
• System files and Message Queuing files
• Archiving Server database data file
• Archiving Server database log file
Based on the typical Lync Server 2010 user model, anticipate around
49 KB of data per day per user. Based on this, database sizing can be
approximated as the following:
DB size = (DB growth per day per user) * (number of users) * (number of days)
For example, with a deployment to 10,000 users that will archive
data for 60 days, anticipated database size is the following for a DB
size of 28 GB:
DB size = (49 KB) * (10,000) * (60)
If an organization varies significantly from the average Lync user model, adjust the growth estimate accordingly.
