Synopsis

This online guide explains briefly the concept of Lync 2010/2013 and how to use a edgeNEXUS Accelerating Load Balancer (ALB-X) to load balance Lync 2010/2013 traffic.

Overview

Microsoft Lync (previously known as Microsoft Office Communications Server) is a real-time communications server for the enterprise. In response to today’s changing working patterns and the need for real-time collaboration, organisations are looking for integrated productivity tools that enable users to communicate from anywhere in a cost-effective and secure manner.

As with any service-oriented architecture, it is essential that applications run seamlessly with superb performance and robust security. The nature of Lync’s real-time communication and collaboration services, together with its business critical importance demands a high level of service delivery.

Enter edgeNEXUS – Application Delivery Control for Microsoft Lync

The edgeNEXUS Accelerating Load Balancer is specifically developed to improve the performance, scalability, reliability and manageability of Microsoft Lync. Easy to deploy, configure and maintain, the jetNEXUS ALB-X for Lync has the simplicity of a plug-and-play solution, with the performance capabilities to meet even the most demanding traffic profiles.

Pre-requisites

The following are general prerequisites and configuration notes for this guide:

• It is assumed that the reader is a network administrator or person familiar with networking and general computer terminology
• You have set-up your Microsoft Lync Enterprise Server 2010 environment and have installed your jetNEXUS ALB-X application delivery controller
• You have configured your internal and external DNS entries for the Front-End and Edge Pools, and services accessed by Reverse Proxy
• When Microsoft refer to a hardware load balancer (HLB) it is equivalent to the industry term “Application Delivery Controller”
• You are running Software Version 4.0.1 (Build 1576) or later on you jetNEXUS ALB-X

Webscheduler

It is advised to create a simple url for webscheduler. This url should map to the same external internet facing IP as meet and dialin.
E.g. you can go to https://ReverseProxyWebfqdnOfPool/scheduler where ReverseProxyWebfqdnOfPool has a separate external internal facing IP or you can create DNS SRV records and forwarding rules for your external interface for external user signin without autodiscover and federation traffic. For further details refer to https://technet.microsoft.com/en-us/library/gg412787.aspx

For user sign-in: _sip._tls. -> your edge external interface FQDN.
For federation: _sipfederationtls._tcp. -> your edge external interface FQDN.

Why jetNEXUS?

LAB Environment

This Guide for Load balancing Microsoft Lync 2010/2013 has been designed on the following configuration.

Lync 2010

• An Enterprise Front End pool, consisting of two nodes. Consolidating Conferencing, Enterprise Voice and Mediation Server features
• Each Front End server was configured on a Microsoft Windows 2008 R2 Server with a single NIC, on a private IP address. Each NIC has a single IP address.
• An Edge pool, consisting of two nodes. Consolidating SIP, Web Conferencing and A/V services. Each of these services is configured using a common IP/Hostname and different ports for each service
• Each Edge server is configured on a Microsoft Windows 2008 R2 Server with two NICs. One on the Private LAN, and another on a DMZ LAN. Each NIC has a single IP address, and the DMZ NIC is configured with a default gateway
• A single Database Server, configured on a Microsoft Windows 2008 R2 Server running Microsoft SQL 2008 R2

Lync 2013

• An Enterprise Front End pool, consisting of two nodes. Consolidating Conferencing, Enterprise Voice and Mediation Server features
• Each Front End server was configured on a Microsoft Windows 2012 Server with a single NIC, on a private IP address. Each NIC has a single IP address.
• An Edge pool, consisting of two nodes. Consolidating SIP, Web Conferencing and A/V services.
• Each of these services is configured using a common IP/Hostname and different ports for each service
• Each Edge server is configured on a Microsoft Windows 2012 Server with two NICs. One on the Private LAN, and another on a DMZ LAN. Each NIC has a single IP address, and the DMZ NIC is configured with a default gateway
• A single Database Server, configured on a Microsoft Windows 2012 Server running Microsoft SQL 2012

Common to Lync 2010 & 2013

• A single PSTN Gateway running a configured SIP trunk
• A Single File Store, a simple file share available on the Private LAN
• No Director, Archiving or Monitoring Servers were configured

Lync 2010/2013 Description

Server Roles

The Front End Server

Lync Front End pool is an array of load balanced servers that provide services to a common group of users.

Front End server functions are:

• Client registration and authentication
• Presence availability information, DL expansion and address book services
• Web conferencing and app sharing
• IM services including IM conferences (chat rooms)

Directors

This role can authenticate Lync Server user requests, but they do not home user accounts or provide presence or conferencing services. Directors are most useful to enhance security in deployments that enable external user access. The Director can authenticate requests before sending them on to internal servers. In the case of a denial-of-service attack, the attack ends with the Director and does not reach the Front End servers

Mediation Server

The Mediation Server is a necessary component for implementing VOIP and voice conferencing. This role processes and translates different VOIP codecs. If you already have an existing VOIP system, you will be running a SIP trunk to your VOIP system. This can be collocated with the Front End server role.

A/V Conferencing Server

A/V conferencing server provides A/V services to Lync clients. This can be installed as a single role or with the Front End server.

Edge Server

Lync Edge Server role is one of the most important server roles because it’s a proxy between internal and external clients. This role allows Lync clients to communicate with users outside company firewalls, which includes external users that may not have an account in your company’s Active directory.

Archiving and Monitoring

This server role monitors your Lync Server usage. Archiving IM conversations, Group Chat and conference logs.

What server role can be load balanced by jetNEXUS ALB-X?

Front End Pool

Deploy Multiple Servers in a pool and use jetNEXUS ALB-X to load balance the traffic

Director Pool

Deploy Multiple Director servers in a pool and use jetNEXUS ALB-X to load balance the traffic

Mediation Pool

The Mediation Service is usually collocated on the Front End Servers

Edge Pool

Deploy Multiple Servers in a pool and use jetNEXUS ALB-X to load balance the traffic

Reverse Proxy

The jetNEXUS ALB-X can be used as a reverse proxy to force HTTP traffic to HTTPs and port address translate 443 to 4443 necessary for External Web Services

Standard Lync Deployment

Diagram 1.1