MS Lync 2013
Contents
2 Introduction
Kemp's LoadMaster family of purpose-built hardware and Virtual Appliances (VLM) offer advanced Layer 4 and Layer 7 server load balancing, content switching, SSL Acceleration and a multitude of other advanced Application Delivery and Optimization (ADC) features.
Kemp's LoadMaster fully supports Microsoft's key solutions and are approved by Microsoft (Kemp is a Microsoft Gold partner). The LoadMaster efficiently distributes user traffic for Microsoft Lync 2013 so that users get the best experience possible.
The entire Kemp LoadMaster product family, including the Virtual LoadMaster (VLM) supports Microsoft Lync 2013.
For more information about Kemp, visit us online at www.kemptechnologies.com.
2.1 Microsoft Lync 2013
Microsoft Lync is a communications tool that provides services such as audio/video conferencing, Instant Messaging (IM) and Voice over Internet Protocol (VoIP). These services can all be accessible from the Internet, or from an internal network. Microsoft Lync allows companies to enhance collaboration amongst employees.
A number of enhancements have been made in Microsoft Lync 2013. The network topology setup is quite similar to the previous version but with a number of small differences. Changes include the consolidation of the archiving and monitoring features towards the front-end servers (optional feature). The Lync 2010 Director role is now optional and is not recommended anymore. Less servers are needed because front-end servers can now take the role of Director.
2.2 Document Purpose
This documentation is intended to provide guidance on how to configure Kemp LoadMaster products to provide high availability for a Microsoft Lync Server 2013 environment. This documentation is created using a representative sample environment described later in the document. As this documentation is not intended to cover every possible deployment scenario it may not address unique setup or requirements. The Kemp Support Team is available to provide solutions for scenarios not explicitly defined.
2.3 Prerequisites
It is assumed that the reader is a network administrator or a person otherwise familiar with networking and general computer terminology. It is further assumed that the Microsoft Lync Server 2013 environment has been set up and the Kemp LoadMaster has been installed.
Other LoadMaster documentation can be referred to as needed from http://www.kemptechnologies.com/documentation.
The minimum requirements that should be met before proceeding are as follows:
- LoadMaster firmware version 7.0-6 or above should be installed
- Configured and published Microsoft Lync Server architecture with Lync Topology builder
- Installed the Microsoft Servers, Active Directories and followed other Microsoft requirements
- Configured internal and external DNS entries for Front-End, Director and Edge pools
- Established access to the LoadMaster Web User Interface (WUI)
3 Load Balancing Microsoft Lync 2013
Deploying a Microsoft Lync environment can require multiple servers in Front-End pools and Edge server pools. Load balancing is necessary in this situation to distribute the traffic amongst these servers.
Microsoft Lync Server 2013 supports two load balancing solutions: DNS load balancing and Hardware Load Balancing (HLB). Hardware load balancers are also required to provide load balancing for the internal and external web services when DNS load balancing is used.
Different load balancing methods cannot be used on the Edge internal and Edge external interfaces, for example, DNS load balancing cannot be used on the Edge internal interface when hardware load balancing is being used on the Edge external interface. Health checking at the LoadMaster ensures that, if one of the servers becomes inaccessible, the load balancer will take the sever offline and automatically re-route and reconnect users to other functioning servers.
Kemp Technology recommend the configuration as depicted in the above diagram. If your configuration differs from the recommended configuration and there are issues deploying the LoadMaster, please contact the local Kemp Support Team for assistance.
4 Template
Kemp has developed a template containing our recommended settings for this workload. You can install this template to help create Virtual Services (VSs) because it automatically populates the settings. You can use the template to easily create the required VSs with the recommended settings. You can remove templates after use and this will not affect deployed services. If needed, you can make changes to any of the VS settings after using the template.
Download released templates from the following page: LoadMaster Templates.
For more information and steps on how to import and use templates, refer to the Virtual Services and Templates, Feature Description.
5 General Configuration
Some recommended general LoadMaster configuration settings are outlined below. These options can be set within the LoadMaster WUI.
5.1 Disable SNAT Globally
By default, global Server Network Address Translation (SNAT) is enabled in the LoadMaster settings. Kemp recommends disabling SNAT globally when using the LoadMaster with a Lync 2013 environment. To disable SNAT globally, follow the steps below:
1. In the main menu, select System Configuration.
2. Select Miscellaneous Options.
3. Select Network Options.
4. Clear the Enable Server NAT check box.
5.2 Subnet Originating Requests
When the LoadMaster is deployed in a two-armed configuration, Kemp recommends enabling Subnet Originating Requests. When this option is enabled, the LoadMaster will use its local IP address, instead of the IP address of the Virtual Service, when communicating to the Real Servers.
Subnet Originating Requests can be enabled on a per-Virtual Service or a global basis.
It is recommended that the Subnet Originating Requests option is enabled on a per-Virtual Service basis.
To enable Subnet Originating Requests globally, follow the steps below:
1. In the main menu of the LoadMaster WUI, select System Configuration > Miscellaneous Options > Network Options.
2. Select the Subnet Originating Requests check box.
5.3 Change Drop Connections Settings
The LoadMaster must be configured to drop connections on Real Server Failure to have fast failover for clients to another Real Server.
1. To configure dropping connections, click System Configuration.
2. Click Miscellaneous Options.
3. Click L7 Configuration.
4. Select the Drop Connections on RS failure checkbox.
5.4 Increase the Connection Timeout
The Loadmaster Connection Timeout must be set to one day. The reason why this value can be set so high is because the LoadMaster monitors client connection to Real Servers and if a server fails then the LoadMaster can drop the associated client connections to that real server. Clients are disconnected from the LoadMaster and then reconnected to the LoadMaster to connect to another Real Server.
One day is the maximum value for this setting and it must be used in conjunction with the Drop Connections on RS failure option.
1. To configure the Connection Timeout, click System Configuration.
2. Click Miscellaneous Options.
3. Click L7 Configuration.
4. Enter 86400 (1 day) in the L7 Connection Drain Time (secs) field and click Set Time.
5.5 Connection Scaling For Large Scale Deployments
Execution of this procedure is optional and should be used only in cases where network traffic is expected to be greater than 64,000 server connections at any one particular time.
L7 Transparency must be disabled to use connection scaling.
1. To use connection scaling, click System Configuration.
2. Click Miscellaneous Options.
3. Click L7 Configuration.
4. Select the Allow connection scaling over 64K Connections checkbox.
5. Click Virtual Services.
6. Click View/Modify Services.
7. Click the Modify button of the appropriate Virtual IP Address.
8. Expand the Advanced Properties section.
9. In the Advanced Properties panel, input a list of Alternate Source Addresses. Multiple IPV4 addresses must be separated with a space; each must be unallocated and allow 64K connections.
10. Click the Set Alternate Source Addresses button.
6 Configuring Virtual Services for Lync 2013
This deployment guide covers three types of Virtual Service; DNS Only, HLB only and those that are common to both types of environment. To configure the Virtual Services using the Application Programming Interface (API), refer to the RESTful API on the Kemp Documentation Page.
The table in each section outlines the API settings and values. You can use this information when using the Kemp LoadMaster API and automation tools.
6.1 DNS Only Configuration
Refer to the sections below for settings when using a DNS only configuration.
Microsoft recommends that DNS load balancing is used for Session Initiation Protocol (SIP) traffic. Microsoft also recommend that web services are configured to override FQDN for internal web services.
Source-IP PersistenceSource IP persistence can be used but take care before enabling it because:
- Clients from behind an NAT device show up as a single IP
- It can result in uneven connection distribution
If cookies are used, there is no negative impact. However, there are some requirements:
- The cookie must be named MS-WSMAN
- It must not expire
- It must not be marked httpOnly
- Cookie optimization should be turned off
To find out the recommended API parameter settings for the various Front-End Virtual Services, refer to the sections below.
6.1.1 Director DNS
The Lync Director DNS template contains three Virtual Services:
- Lync Internal WebSvc HTTPS Virtual Service
-
Lync Director 2013
- Lync Internal WebSvc HTTP
6.1.1.1 Deploy Director DNS Template
To add the Virtual Services for Skype Director DNS with the template, follow the steps below:
1. Click the Add New button.
2. Enter a Virtual Address.
3. Select the Lync Director DNS template from the Use Template drop-down list.
4. Click Add This Virtual Service.
6.1.1.2 Configure Director DNS Template
To configure the Lync Director Virtual Service, follow the steps below:
1. Select View/Modify Services under Virtual Services in the left-hand navigation.
2. Click Modify on the Lync Director Virtual Service.
3. Expand the Real Servers section.
4. Click Add New.
5. Enter the Real Server Address.
6. Confirm that Port 443 is entered.
7. Click Add This Real Server.
8. Add additional Real Servers as needed.
6.1.1.3 Lync Internal WebSvc HTTPS Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
Option |
Value |
|---|---|
| port | 443 |
| prot | tcp |
| ForceL7 | 1 |
| ExtraPorts | 4443 |
| Transparent | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.1.1.4 Lync Director 2013 DNS Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
Value |
|---|---|
| port | 443 |
| prot | tcp |
| ExtraPorts | 444,4443 |
| Transparent | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.1.1.5 Lync Internal WebSvc HTTP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| port | 80 |
| prot | tcp |
| ExtraPorts | 8080 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedulei | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2 HLB Only Configuration
Refer to the sections below for settings using an HLB only configuration.
6.2.1 Lync Director 2013 HLB Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| ExtraPorts | 444,4443 |
| Transparent | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.2 Lync Internal Director SIP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
6.2.3 Lync Mediation Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameters |
API Value |
|---|---|
| port | 5070 |
| prot | tcp |
| VStype | gen |
| ForceL7 | 1 |
| Transparent | 0 |
| ServerInit | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedulei | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5070 |
6.2.4 Lync Edge Internal AV Media TCP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameters |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| VStype | gen |
| ForceL7 | 1 |
| Transparent | 0 |
| ServerInit | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | TCP Connection Only |
| CheckPort | 5061 |
6.2.5 Lync Edge Internal AV Media UDP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| CheckType | icmp |
6.2.6 Lync Edge Internal SIP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| port | 5061 |
| prot | tcp |
| VStype | gen |
| ExtraPorts | 5062 |
| ServerInit | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.7 Lync Internal WebSvc HTTP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameters |
API Value |
|---|---|
| port | 80 |
| prot | tcp |
| ExtraPorts | 8080 |
| Persist | src |
| Persist | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.8 Lync Internal Front-End DCOM Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameters |
API Value |
|---|---|
| port | 135 |
| prot | tcp |
| Transparent | 0 |
| ServerInit | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.9 Lync Internal WebSvc HTTPS Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameters |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| ForceL7 | 0 |
| ExtraPorts | 4443 |
| Transparent | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.10 Lync Internal Front-End SIP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| port | 5061 |
| prot | tcp |
| VStype | gen |
| ForceL7 | 1 |
| ExtraPorts | 448,5070-5073,5075,5076,5080 |
| Transparent | 0 |
| Server Init | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType s | tcp |
| CheckPort | 5061 |
6.2.11 Configure Edge Virtual Services Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
When load balancing external interfaces of Edge pools, the shared interface IP should be used as the default gateway on all Edge interfaces. Also, a publicly routable IP with no NAT or port translation must be used.
6.2.11.1 Lync Edge External AV Media UDP Virtual Service Recommended API Settings (optional)
|
Option |
Value |
|---|---|
| port | 3478 |
| prot | udp |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| CheckType | icmp |
6.2.11.2 Lync Edge External SIP Virtual Service Recommended API Settings (optional)
|
API Parameters |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| ForceL7 | 1 |
| Transparent | 0 |
| Persist | src |
| PersisTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.11.3 Lync Edge External SIP Federation Virtual Service Recommended API Settings (optional)
|
API Parameters |
API Value |
|---|---|
| port | 5061 |
| prot | tcp |
| ForceL7 | 1 |
| Transparent | 0 |
| Persistent | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.11.4 Lync Edge External XMPP Virtual Service Recommended API Settings (optional)
|
API Parameter |
API Value |
|---|---|
| port | 5269 |
| prot | tcp |
| ForceL7 | 1 |
| Transparent | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
6.2.11.5 Lync Edge External Conferencing Virtual Service Recommended API Settings (optional)
|
API Parameter |
API Value |
|---|---|
| ForceL7 | 1 |
| Transparent | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 443 |
*It is optional to add a HTTP redirector Virtual Service. Whether you require one or not depends on your environment.
6.2.11.6 Lync Edge External AV Media TCP Virtual Service Recommended API Settings (optional)
|
API Parameter |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| ForceL7 | 1 |
| Transparent | 1 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 443 |
6.3 Common to Both
The Virtual Services listed below are common to both DNS and HLB configurations.
6.3.1 Lync Office Web App Servers Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameters |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| SSLAcceleration | 1 |
| SSLReencrypt | 1 |
| Persist | super and src |
| Persist | 1800 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | https |
| CheckURL | /hosting/discovery |
| CheckUse | 1 |
| CheckUseGet | GET |
*It is optional to add a HTTP redirector Virtual Service. Whether you require one or not depends on your environment.
6.3.2 Lync Director Reverse Proxy HTTP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameters |
API Value |
|---|---|
| port | 80 |
| prot | tcp |
| ForceL7 | 1 |
| Transparent | 0 |
| Persist | src |
| Persist | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
1. Add any Real Servers as needed.
6.3.3 Lync Director Reverse Proxy HTTPS Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| SSLAcceleration | 1 |
| SSLReencrypt | 1 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType Parameters | tcp |
| CheckPort | 5061 |
Add any Real Servers as necessary.
6.3.4 Lync Front End Reverse Proxy HTTP Virtual Service Recommended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| port | 80 |
| prot | tcp |
| ForceL7 | 1 |
| Transparent | 0 |
| Persist | src |
| PersistTimeout | 1200 |
| Idletime | 1800 |
| CheckType Parameters | tcp |
| CheckPort | 5061 |
Add any Real Servers as necessary.
6.3.5 Lync Front End Reverse Proxy HTTPS Virtual Service Re commended API Settings (optional)
This table outlines the API parameters and values set using the Kemp application template. These settings can be used with scripts and automation tools.
|
API Parameter |
API Value |
|---|---|
| port | 443 |
| prot | tcp |
| SSLAcceleration | 1 |
| SSLReencrypt | 1 |
| Persist | src |
| PersistTimeout | 1200 |
| Schedule | lc |
| Idletime | 1800 |
| CheckType | tcp |
| CheckPort | 5061 |
Add any Real Servers as required.
7 References
The following sources are referred to in this document:
Kemp website
Kemp Documentation page
http://kemptechnologies.com/loadmaster-documentation.
MS Lync 2013 Single Pair Addendum, Deployment Guidehttp://www.kemptechnologies.com/documentation
Web User Interface (WUI), Configuration Guide
http://www.kemptechnologies.com/documentation
Virtual Services and Templates, Feature Description
http://www.kemptechnologies.com/documentation
Ports and Protocols for Internal Servers
1. http://technet.microsoft.com/en-us/library/gg398833.aspx
Port Summary - Scaled Consolidated Edge with Hardware Load Balancers
2. http://technet.microsoft.com/en-us/library/gg398739.aspx
Scaled Consolidated Edge with Hardware Load Balancers
3. http://technet.microsoft.com/en-us/library/gg398478.aspx
Last Updated Date
This document was last updated on 20 June 2022.