MACROMEDIA COLDFUSION 4.5-ADMINISTRING COLDFUSION SERVER Manual page 262

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apart. To achieve the desired effect described in the latter scenario, it's best to set a
differential of at least 10% between the two threshold values.
Configuring the ColdFusion probe
ClusterCATS load balances and provides failover support for your ColdFusion
applications in two ways. First, it automatically interprets and reacts to the load metric
that the ColdFusion Server generates. Second, ClusterCATS lets you create ColdFusion
application probes that periodically test the health and operation of the sites that the
ColdFusion Server processes.
The probe is a high availability feature that verifies that the ColdFusion Server is
running properly on your clustered servers. It periodically tests a specific ColdFusion
URL over periodic intervals and verifies its validity against a user-defined string that is
contained in the returned page.
If the validation test succeeds, inbound HTTP requests will continue to be sent to the
server for which a probe exists. However, if the test fails (the URL fails, times out, or
does not return the user-specified string in the page accessed), ClusterCATS restricts
the server and redirects requests to other available servers in the cluster. The restricted
server will become available as soon as the probe returns a valid value.
Additionally, if the ColdFusion Server ever hangs or fails, ClusterCATS automatically
attempts to recover the failed service. Once the ColdFusion service is recovered, the
probe will automatically restart the ColdFusion Server and send HTTP traffic to the
server.
To configure the ColdFusion probe:
1. Open the ClusterCATS Web Explorer if it's not already open.
2. Click the Show Cluster link.
The Show Cluster page appears.
Administering ColdFusion Server