Managing BizTalk Hosts and Host Instances

A BizTalk Host is a set of running engines—BizTalk Message Queuing (MSMQT), XLANG, and Tracking Data Decode Service (TDDS)—that communicate with the MessageBox database. A BizTalk Host is a logical set of zero or more BizTalk runtime processes in which you deploy items such as adapter handlers, receive locations (including pipelines), and orchestrations. A host instance is the place where the message processing, receiving, and transmitting occurs. You install a host instance on each Microsoft® BizTalk® Server computer that has one or more hosts mapped to that server.

Hosts have the following characteristics:

  • Hosts are the logical containers of BizTalk objects.
  • Only one instance of a specific host can exist on each server.
  • You can map one host to multiple servers.

Host instances have the following characteristics:

  • Host instances running on the servers are the physical containers of BizTalk objects.
  • You create a host instance when you map a server to a host.
  • Multiple host instances (of different hosts) can exist on a server.

The following figure shows the relationship between servers, hosts, and host instances.

Relationship between hosts and servers

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