Specifications

19 Reference Architecture | Dell
TM
Unified Communication Solution with Microsoft® Lync® Server 2013 for Single Site
Implementation | Version 1.0
3.2.4.2 Lync-Specific Best Practices
Shown below are some of the best practices specific to Lync:
• Use two Lync Standard Edition Server in a paired pool or three Lync Front Ends in an Enterprise pool.
Doing so abides by the Microsoft Best Practice. This ensures best use of the “brick architecture”
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in
Lync Server 2013 Enterprise Edition and that there is a copy of user data on each of the three Front
Ends.
• Place similar VMs on separate hosts. There are a few different Lync Server 2013 roles in the
deployment. By placing like roles on different hosts, IT administrators can ensure there is no loss of
availability if one host fails.
• Use a minimum of six disks for the SQL data store. The official Microsoft recommendation is to also
use six disks
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for SQL Server databases. This recommendation ensures that there is sufficient disk
performance during periods of high I/O, such as durations with high user login rates. There are a
number of different DB-Log pairs within the SQL architecture for Lync:
o Xds—for information about the topology used by the Central Management Store
o Rtcdyn— for transient user data, such as presence
o Rtc— for persistent data, such as contact lists and contacts
o Lcslog, LcsCdr and QoEMetrics—for archiving and monitoring database and log requirements
o Rtcab—to store Lync address books
o Rgsdyn, Rgsconfig—to store database and log information for response groups
o And many others
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• For SQL Server, it is preferable to place the tempdb within the SQL store and not in the default system
volume location. The tempdb database is the working “scratch pad” that SQL uses to perform
operational tasks. Placing it on the system volume can cause unwanted disk contention.
• There should be adequate network provisioning to accommodate audio and video traffic that Lync
enables. Allocate 65Kbps per audio stream and 500Kbps per video stream.
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• Sufficient memory must be allocated for each of the Lync Server roles.
• Use statically assigned memory instead of dynamic memory. The use of fixed amounts of memory for
each VM provides resources that may be required at all times instead of allocation on demand by the
hypervisor to each VM. Considering that Lync 2013 is a real-time workload, using dynamic memory
may cause unwanted latencies in delay-sensitive audio/video traffic. For example, during peak hours
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For details, see “Lync Server 2013: Keep in touch” in TechNet magazine: http://technet.microsoft.com/en-
us/magazine/jj839700.aspx
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For details, see “Server Hardware Platforms” on TechNet: http://technet.microsoft.com/en-us/library/gg398835(OCS.15).aspx
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For more examples, see “SQL Server Data and Log File Placement” on TechNet: http://technet.microsoft.com/en-
us/library/gg398479.aspx
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http://technet.microsoft.com/en-us/library/gg425841.aspx