A BizTalk Host is a logical set of zero or more BizTalk runtime processes in which you configure to run items such as adapter handlers, receive locations (including pipelines), and orchestrations. A host instance is the physical process (NT Service) that's created in BizTalk servers where the message processing, receiving, and transmitting occurs.
BizTalk server provides the capability for the users to control the state of the host instances (start, stop, enable, disable) through the BizTalk Server Administration Console. Any of these operations can have consequences on the business operations. For instance, if a tracking host instance (which is responsible for moving DTA and BAM tracking data from MessageBox database to DTA and BAMPrimaryImport databases) is accidentally stopped, the data transfer will not happen as expected. This will bloat up the MessageBox database size and result in performance issues.
On a different example if the host instance responsible for receive or transmitting messages is kept in a disabled or stopped state, then BizTalk server will not receive or transmit messages, which could be serious.
So, it becomes more important to keep track of health of the BizTalk host instance by monitoring as well as keep an eye on who is performing any activities on the host instance.
BizTalk360 has the inbuilt capability to record the user activities performed on the host instances. The Super User, by default, can view the audit logs in the Governance/Auditing section. Super users also have the ability to authorize normal users from the User Access Policy section to view the Governance/Auditing information.
The below screenshot sliders show how the audit logs are captured when a user enables and starts a host instance (BizTalkServerApplication) that is previously stopped and disabled.