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212 Administering ColdFusion Server
Combining ClusterCATS and LocalDirector provides a powerful ColdFusion-aware
load balancing solution that LocalDirector cannot provide without ClusterCATS.
LocalDirector by itself cannot accurately detect how busy a ColdFusion Server is nor
can it redirect load from failed or busy servers to available servers. It, therefore, would
continue to send new requests to a server even if ColdFusion is too busy to handle
additional requests or if the server has failed.
ClusterCATS can detect if a ColdFusion Server is too busy to handle additional requests
because it can interpret the ColdFusion load metric. It can also monitor the operation
of the ColdFusion Server on a periodic basis using ColdFusion probes. Consequently,
its built-in intelligence can override the regular distribution sequence of the router,
and it can redirect new requests to other available servers in the cluster. So, it not only
load balances, but it also provides important ColdFusion Server availability data as
well.
Note
When using ClusterCATS and LocalDirector together, do not use round-
robin DNS. Also, it’s best to turn off the Gradual Redirection load
threshold when using these two load balancing technologies together.
See “Configuring server load thresholds” on page 203 for turning off
gradual redirection.
This section describes the following procedures:
•
To integrate ClusterCATS with Cisco LocalDirector
•
To integrate ClusterCATS with a load balancing device other than LocalDirector
To integrate ClusterCATS with Cisco LocalDirector
1. Make sure you are using LocalDirector version 3.1.3 or later.
LocalDirector versions prior to version 3.1.3 don’t support Dynamic Feedback
Protocol.
2. Create a virtual server (www.website.com) in LocalDirector that corresponds to
the cluster.
3. In LocalDirector, bind explicit (real) servers participating in the cluster with the
virtual server.
4. Use the Predictor command in LocalDirector to configure the virtual server to use
the Weighted load balancing option.
Note
See the Cisco LocalDirector documentation that came with the
product for detailed procedures about configuring Cisco
LocalDirector.
5. Use LocalDirector’s Dynamic Feedback Protocol (DFP) command to specify the IP
addresses of each explicit server (cluster member) and the port number each
server will use to listen for DFP requests from the LocalDirector.
6. Open the ClusterCATS Explorer and select the cluster that you want to integrate
with LocalDirector.