Routing rules for generic server clusters
Set the advanced configuration routing rules to ensure work requests arrive at the proper generic server cluster. From this topic we can create, delete, or modify a routing rule.
From the admin console, click...
Servers > Server Types > WebSphere proxy servers > proxy_server > HTTP Proxy Server Settings > Routing Rules
Before creating routing rules, which are used to route requests to servers, define a generic server cluster...
Servers > Clusters > Generic server clusters > URI group > Environment > URI groups
Optionally appropriate virtual hosts...
Environment > Virtual hosts > default host
Routing rules are used to assist the routing of work requests to non-IBM application server nodes. In addition, using routing rules, a system administrator can reroute work without heavily impacting the environment. This capability is useful when nodes are taken down for maintenance.
For example, the system administrator can set up a routing rule to route /images/* to the ImageServerCluster generic server cluster. If the ImageServerCluster cluster has to come down, the administrator can then route /images/* to another cluster with similar capability, or use a redirect rule. This situation explains why the URI group can be defined independently of the generic server cluster. If the generic server cluster must come down, the URI group can be rerouted elsewhere. When creating the generic server cluster by providing a name, we can configure the cluster using the ports link to create the actual cluster members.
Routing rules function using the configured virtual hosts and URIs as matching criteria. The proxy server scans all incoming requests and compares the URI and host header from it and matches it against the virtual host and URIs configured in the rule. We must create the URI group for a routing rule before creating the routing rule. If we are routing to a generic server cluster, we must also create the cluster before defining the routing rule. Create the URI group by completing the following tasks:
- Create the routing rule name.
- Determine to enable this rule. Create routing rules and not enable them. This capability is useful when planning for the maintenance of nodes or for emergency planning.
- Select the virtual host name from the drop-down menu. The virtual host name field is a selectable field that is preconfigured with the defined virtual hosts in the cell. If we do not see the virtual host that we want in the menu, click Environment > Virtual hosts and define the host there.
- Select the URI group for the routing rule. The URI group field is populated with all the preconfigured URI groups in the cell. If we do not see the URI group that we are looking for, click Environment > URI groups and create one.
- Select and define a routing rule. This option specifies how to route a request that matches the defined virtual host and URI group. The three options for this field are:
- Generic Server Cluster: Routes requests to a preconfigured generic server cluster. Use the drop-down box to select the generic server cluster.
- Fail: Rejects requests by returning the specified HTTP status code.
- Redirect: Redirects a client to the specified URL. This option can be used to ensure a request is routed through SSL.
Name
The name field is required and is a user-defined field.
The name field cannot contain the following characters: # \ / , : ; " * ? < > | = + & % '
The name that is defined must be unique among routing rules and cannot begin with a period or a space. A space does not generate an error, but leading and trailing spaces are automatically deleted.
Routing requests from a plug-in to a proxy server