Introduction

A key non-functional requirement for a BizTalk Server deployment can be availability. When you want BizTalk to be able to receive, process and send messages 24x7 you will need to design a deployment that provides high availability. This requires implementing redundancy for each functional component involved in an application integration or business process integration scenario. Running multiple host instances and clustering the BizTalk Server databases high availability can be achieved (separating data from the hosts that process the data). High availability for BizTalk Server means:

• Separate hosts and run multiple host instances: Different hosts for receiving messages, processing orchestrations, sending messages and tracking completed transactions. BizTalk automatically distributes workload across multiple instances, so clustering hosts is not required. However, hosts running the receive handler for the HTTP, SOAP, and BizTalk Message Queuing (MSMQT) adapters require a load-balancing mechanism such as Network Load Balancing (NLB) to provide high availability.

• Clustering the BizTalk Server databases: Clustering of BizTalk databases typically consists of two database instances on separate machines configured in an active/passive server cluster configuration. Both sharing a common disk resource (such as a RAID5 SCSI disk array or storage area network) and use Windows Clustering to provide backup redundancy and fault tolerance.

This article will further provide resources to enable you to efficiently plan, deploy and validate a high available BizTalk environment.

MSDN

MDSN is a huge online repository for Microsoft documentation. This should be your primary source for information on BizTalk availability:   

• Planning Your Platform for Fault Tolerance
• Creating a Highly Available BizTalk Server Environment
• Sample BizTalk Server High Availability Scenarios
• High Availability for Enterprise Single Sign-On
• High Availability and the Microsoft Operations Framework
• Getting Started with SQL Server 2008 Failover Clustering
• Windows Server Failover Clustering (WSFC) with SQL Server
• Improving Fault Tolerance in BizTalk Server by Using a Windows Server Cluster

Articles

The following articles provide more information on High Availability for BizTalk:

• Recommendations for Installing, Sizing, Deploying, and Maintaining a BizTalk Server Solution
• White Paper: SQL Server 2008 Failover Clustering

Blogs

The following blog posts by community provide more background information and experience on High Availability for BizTalk:

• Clustering BizTalk Hosts
• BizTalk High Availability Host Separation
• Installation of SSO on SQL Cluster
• BizTalk High Availability Server Environment –BizTalk 2010 Installation, Configuration and Clustering
• How To Cluster BizTalk's MSMQ Receive Adapter - Windows 2008 Server
• BizTalk High Availability Server Environment – Preparations

Webcasts

The following web casts by community provide more background information on High Availability for BizTalk:

• Creating a Highly Available BTS 09 Environment
• MSDN Webcast: High Availability, Fault Tolerance and Scalability with BizTalk Server 2006

See Also

Another important place to find a huge amount of BizTalk related articles is the TechNet Wiki itself. The best entry point is BizTalk Server Resources on the TechNet Wiki.

Read suggested related topics:

• Improving Fault Tolerance in BizTalk Server by Using a Windows Server 2008 Failover Cluster or Windows Server 2003 Server Cluster
• BizTalk Server 2010 Scale-out Configurations Poster
• Microsoft BizTalk Server 2010 Performance Optimization Guide