Clustered Host Instances
To achieve high availability for adapters that cannot have multiple host instances running at one point in time, BizTalk allows you to cluster hosts using Windows Failover Clustering which will make only one host instance running for the clustered host and in case of any failure it will failover by running the host instance in a different server.
Clustered Host Instances in BizTalk360
Once the clustered host instances are created, you can see identify these host in the list of host instances in BizTalk360 under the 'Host Instances' section.
You can see that one host instance (BizTalkServerApplication) has been created on both servers, and one of them is in Started state while the other is in Stopped state. We have appropriate icons in place to differentiate the clustered host instances from the normal ones.
Starting/Stopping Clustered Host Instances
Starting/stopping a clustered host instance is not the same as doing a normal host instance. To start/stop a clustered host instance, you need to follow the pattern:
- Stopping a clustered host instance is pretty straight forward. You can select the host instance and click Stop
- Starting a clustered host instance will actually start the cluster group instead of the selected host instance
Monitoring Clustered Host Instances using BizTalk360
BizTalk360 has the capability of monitoring clustered host instances. Monitoring clustered instances is the same as monitoring all other artifacts in a BizTalk server environment. You need to Create an Alarm and associate the alarm with the artifacts in order to be able to monitor the host instances. In this case, configuring monitoring for clustered host instances happens in the same place as normal host instances in BizTalk Environments.
The host instances created on multiple servers are displayed under Host Instances tab of BizTalk Environment section. For a non-clustered host instance, you can monitor them on one of the following states — Started, Stopped, or Disabled. However, for a clustered host instance (since only one needs to be active at any point of time), you need to monitor by choosing the state — AtleastOneActive. Monitoring on this expected state will keep a watch on the clustered host instance to see if one of the two host instances are active at any point of time. If no host instance for the clustered host is active BizTalk360 will trigger an alert and a notification will be sent to your notification channels.
Depending on the status of the host instances, you will receive the notification email from BizTalk360 as below:
Setting up monitoring of Clustered Host Instances
- Log in to the BizTalk360 application
- Click 'Monitoring' in the Navigation panel
- Click the expand button against 'Manage Mapping' tab and select 'BizTalk Environment' link
- Select the Alarm name (see Creating an alarm) from the drop down for which you would like to associate the alerts
- In the list of system resources at the top, select Host Instances
- Select the check boxes against the clustered host instances (BizTalkServerApplication) that you wish to monitor
- Set the value of Expected State as AtleastOneActive by selecting from the values from drop down. Setting the value as AtleastOneActive sets the value to both the clustered Host Instances
- When there is a violation in the threshold, BizTalk360 triggers an alert and sends the notification through the notification channels