Checklist: Providing High Availability with Fault Tolerance or Load Balancing

This topic lists steps that you should complete to configure fault tolerance and/or load balancing for the components of a production BizTalk Server environment to provide high availability. Configuration of fault tolerance for these components will allow the system to continue operating if a particular component fails.

Steps Reference

Create multiple BizTalk host instances and implement host clustering support for those adapters that require it.

High Availability for BizTalk Hosts

Configure tracking hosts for high availability.

High Availability for BizTalk Hosts

Configure the BizTalk Server databases on a clustered SQL Server instance on a Windows server cluster.

High Availability for Databases

Configure tracking hosts for high availability. Verify that there are at least N+1 host instances with tracking enabled where N is the number of MessageBox databases in the BizTalk group.

To enable tracking for a host, check the option to Allow Host Tracking on the Host Properties dialog box available from the BizTalk Server Administration console. For more information about setting Host Properties, see the topic "How to Modify Host Properties" in BizTalk Server 2006 R2 Help at

Practice database failover regularly to ensure failover functionality.

This responsibility should be directly assigned to ensure that this is done on a consistent basis.

Verify there is enough processing power and memory on the passive cluster node(s) to enable multiple SQL Server instances to run simultaneously in failover scenarios.

If two SQL instances regularly consume over 50 percent of the resources on a cluster node, then when both instances failover to a single node, each instance will incur degraded performance. Therefore, testing should be performed to ensure that a single cluster node will be able to handle the load until the failed node is brought back online. If a single node cannot handle the load of both SQL instances then consider adding additional cluster nodes to implement an Active/Active/Passive cluster topology.

Implement a storage area network (SAN) to house the BizTalk Server databases.

If possible, configure the SAN disks using RAID 1+0 (a stripe of mirror sets) topology for maximum performance and high availability.

In the "BizTalk Server Database Optimization" white paper, see the "Disk Infrastructure" section under "Performance Tuning" at

Use Windows Clustering to cluster the Enterprise Single Sign-On (ENTSSO) master secret server.

High Availability for the Master Secret Server

Do not cluster the SSO service on a computer running BizTalk Server unless you cluster SSO and a BizTalk host in the same cluster group. For more information about clustering the SSO service and a BizTalk Server host in the same cluster group see "How to Cluster SSO and a BizTalk Host in the Same Cluster Group" at

Back up the Enterprise Single Sign-On (ENTSSO) Master Secret.

How to Back Up the Master Secret

Configure the Internet Information Services (IIS) Web server for isolated host instances, the BAM Portal Web page, and the Human Workflow Services (HWS) Web service to be highly available using Network Load Balancing (NLB) or other load balancing device.

"Network Load Balancing: Configuration Best Practices for Windows 2000 and Windows Server 2003" at

Configure the Windows SharePoint Services (WSS) server for Business Activity Services (BAS) to be highly available using Network Load Balancing (NLB).

Configure the BizTalk Server Base EDI adapter for high availability:

  • Configure a heartbeat mechanism for the EDI Subsystem.

  • Create a clustered file share resource for the EDI Subsystem.

  • Create multiple instances of the EDI adapter handlers.

    The Base EDI Adapter is deprecated in BizTalk Server 2006 R2.

"High Availability for the BizTalk Base EDI Adapter" at