IT tutorials
 
Applications Server
 

Microsoft Lync Server 2013 : Dependent Services and SQL - Domain Name System - DNS Load Balancing , Automatic Client Sign-in

12/14/2014 8:25:17 PM
- How To Install Windows Server 2012 On VirtualBox
- How To Bypass Torrent Connection Blocking By Your ISP
- How To Install Actual Facebook App On Kindle Fire

Lync Server heavily relies on domain name system (DNS) for name resolution and service lookups. Since Lync is always installed in an Active Directory environment, which also requires DNS, this service is typically already in production before the installation of Lync, and therefore simply needs to be configured to meet Lync requirements.

Lync Server utilizes DNS for several purposes. First, there is the requirement for hostname–to–IP address lookups, which is the typical use of DNS. However, Lync Server also uses specialized DNS records to identify particular services. Lync Server is also able to leverage DNS round robin functionality to provide load balancing for specific Lync functions. The DNS record types that are primarily used by Lync are the following:

• A, or host records

• SRV, or service location records

A very basic Lync deployment involving only the core services requires only a few DNS records. However, as additional Lync features and services are deployed in the environment, quite a few additional DNS records might be required. For example, edge services, the Device Update Web service, and Lync Mobility all have specific DNS requirements. In this section, the DNS records required to allow basic Lync functionality are covered.

Lync Server requires registration of the hostname for each Lync server as an internal A record. For Standard Edition, a DNS A record that resolves the fully qualified name of the pool to the IP address of the Front End server is also needed. For Enterprise Edition Front End pools involving a hardware load balancer, a DNS A record that resolves the fully qualified name of the pool to virtual IP address of the load balancer is needed.

DNS Load Balancing

Lync Server 2013 provides the option to employ DNS load balancing in combination with hardware load balancing to split the incoming Lync server traffic across the two load-balancing mechanisms for an Enterprise pool. With this configuration, the HTTP traffic is load balanced using a hardware load balancer, whereas the SIP and media traffic is load balanced using DNS. To enable this functionality, a very specific DNS configuration is required. First, two DNS A records are used to resolve the fully qualified name of the pool to the IP address of each of the Front End servers. An additional DNS A record is then used to resolve the fully qualified name of the pool web components service to the virtual IP address of the load balancer. The following is a sample DNS configuration that leverages both DNS load balancing and hardware load balancing for an Enterprise pool:

EntFE1.companyabc.com    A  10.1.1.2  Standard host record
EntFE2.companyabc.com    A  10.1.1.3  Standard host record
LyncPool.companyabc.com  A  10.1.1.2  DNS load balancing for SIP and media traffic
LyncPool.companyabc.com  A  10.1.1.3  DNS load balancing for SIP and media traffic
LyncWeb.companyabc.com   A  10.1.1.4  Hardware load balancing for HTTP traffic

Automatic Client Sign-in

Although the sample DNS configurations just shown can be used to meet the minimum requirements for Lync, many organizations rely on the Lync client’s capability to automatically find the Lync pool and sign in the user, an optional but very useful feature. To provide automatic client sign-in, an SRV record is required for _sipinternaltls._tcp.<domain> over port 5061 that maps to the fully qualified name of the pool. For example, Figure 1 shows the configuration of the SRV record that would be added to the sample DNS configuration shown previously to provide automatic client sign-in for the companyabc.com Lync deployment.

Image

Figure 1. SRV record used for automatic client sign-in.

Note that SRV records hold information that is not used with other types of DNS records, such as priority, weight, and port number. In addition to specifying the location of the service, this information provides a means to influence how the incoming traffic load will be shared or directed.


Tip

For Lync deployments that use several SIP domains, one SRV record is required for each domain to support automatic client sign-in.

Simple URLs

An additional Lync feature that affects the DNS configuration is simple URLs. Simple URLs are used to provide access to common Lync services using names that are easy to remember. Lync Server 2013 provides the capability to configure simple URLs for three services: web conferencing, dial-in conferencing, and administrative access to the Lync Server Control Panel. Several options are available for the configuration of simple URLs, and each requires the configuration of at least one DNS A record for the simple URL to function. For the majority of Lync deployments, the option to use a separate base URL for each simple URL is used, because this configuration results in a naming convention that is typically the easiest for users to remember. For this configuration, each of the simple URLs requires one DNS A record that resolves the URL to either the Front End server (for Standard Edition) or the virtual IP address of the hardware load balancer (for Enterprise Edition). The following is an example of a DNS configuration that might be used to add simple URLs for the companyabc.com Lync deployment:

meet.companyabc.com       A  10.1.1.4   Simple URL for web conferencing
dialin.companyabc.com     A  10.1.1.4   Simple URL for dial-in access to meetings
lyncadmin.companyabc.com  A  10.1.1.4   Simple URL for access to the Lync Server
                                        Control Panel

 
Others
 
- Microsoft Lync Server 2013 : Dependent Services and SQL - Active Directory (part 2) - Forest Prep, Domain Prep, Lync Server 2013 Security Groups
- Microsoft Lync Server 2013 : Dependent Services and SQL - Active Directory (part 1) - Schema Extensions
- Administering Active Directory 2008 : Creating and Managing Active Directory Objects (part 4) - Moving, Renaming, and Deleting Active Directory Objects , Resetting an Existing Computer Account
- Administering Active Directory 2008 : Creating and Managing Active Directory Objects (part 3) - Understanding Groups, Filtering and Advanced Active Directory Features
- Administering Active Directory 2008 : Creating and Managing Active Directory Objects (part 2) - Managing Object Properties
- Administering Active Directory 2008 : Creating and Managing Active Directory Objects (part 1) - Overview of Active Directory Objects
- Sharepoint 2010 : Windows PowerShell Remoting (part 2) - Entering a Remote Session, Running SharePoint 2010 Cmdlets Remotely
- Sharepoint 2010 : Windows PowerShell Remoting (part 1)
- Sharepoint 2010 : Windows PowerShell Scripts (part 3) - Writing Comment-Based Help Topics in Scripts,Using Functions in Scripts , Customizing Windows PowerShell with Profile Scripts
- Sharepoint 2010 : Windows PowerShell Scripts (part 2) - Executing Scripts, Using Parameters in Scripts
 
25 Inspiring Game of Thrones Quotes
 
Top 10
 
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Finding containers and lists in Visio (part 2) - Wireframes,Legends
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Finding containers and lists in Visio (part 1) - Swimlanes
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Formatting and sizing lists
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Adding shapes to lists
- Microsoft Visio 2013 : Adding Structure to Your Diagrams - Sizing containers
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 3) - The Other Properties of a Control
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 2) - The Data Properties of a Control
- Microsoft Access 2010 : Control Properties and Why to Use Them (part 1) - The Format Properties of a Control
- Microsoft Access 2010 : Form Properties and Why Should You Use Them - Working with the Properties Window
- Microsoft Visio 2013 : Using the Organization Chart Wizard with new data
programming4us programming4us
 
Popular tags
 
Video Tutorail Microsoft Access Microsoft Excel Microsoft OneNote Microsoft PowerPoint Microsoft Project Microsoft Visio Microsoft Word Active Directory Biztalk Exchange Server Microsoft LynC Server Microsoft Dynamic Sharepoint Sql Server Windows Server 2008 Windows Server 2012 Windows 7 Windows 8 Adobe Indesign Adobe Flash Professional Dreamweaver Adobe Illustrator Adobe After Effects Adobe Photoshop Adobe Fireworks Adobe Flash Catalyst Corel Painter X CorelDRAW X5 CorelDraw 10 QuarkXPress 8 windows Phone 7 windows Phone 8 BlackBerry Android Ipad Iphone iOS