Using Clusters
Configuring BIG-IP Hardware with Clusters
This section describes options for configuring an F5 BIG-IP controller to operate with a WebLogic Server cluster. For detailed setup and administration instructions, refer to your F5 product documentation.
For information about how WebLogic Server works with external load balancers, see Load Balancing HTTP Sessions with an External Load Balancer.
Configuring Session Persistence
BIG-IP supports multiple types of cookie persistence. To work with a WebLogic Cluster, configure BIG-IP for the Insert Mode form of HTTP Cookie Persistence. Insert mode insures that the WebLogic Server cookie is not overwritten, and can be used in the event that a client fails to connect to its primary WebLogic Server.
To configure Insert mode for BIG-IP cookies:
- Open the BIG-IP configuration utility.
- Select the Pools option from the navigation pane.
- Select the an available pool to configure.
- Select the Persistence tab.
- Select Active HTTP Cookie to begin configuring cookies.
- Choose Insert mode from the list of methods.
- Enter the timeout value for the cookie. The timeout value specifies how long the inserted cookie remains on the client before expiring. Note that the timeout value does not affect the WebLogic Server session cookie—it affects only the inserted BIG-IP cookie.
To load balance requests on a round-robin basis, set the timeout value to zero—this ensures that multiple requests from the same client are directed to the same managed server, and that a request from a different client is routed to another managed server in the cluster, in round-robin fashion.
When the timeout value is set to a value greater than zero, the load balancer sends all requests from all clients to the same managed server in the WebLogic Server cluster for the duration of the timeout period—in other words, requests from different clients will not be load balanced for the duration of the timeout.
- Apply your changes and exit the utility.
Configuring URL Rewriting
BIG-IP Version 4.5 provides support for URL rewriting.
Configuring WebLogic Server for URL Rewriting
In its default configuration, WebLogic Server uses client-side cookies to keep track of the primary and secondary server that host the client's servlet session state. In addition, WebLogic Server can also keep track of primary and secondary servers using URL rewriting. With URL rewriting, both locations of the client session state are embedded into the URLs passed between the client and proxy server. To support this feature, ensure that URL rewriting is enabled on the WebLogic Server cluster. For instructions on how to enable URL rewriting, see “Using URL Rewriting Instead of Cookies” in Developing Web Applications, Servlets, and JSPs for Oracle WebLogic Server.
Configuring BIG-IP for URL Rewriting
Use of URL rewriting with BIG-IP and WebLogic Server instances requires BIG-IP version 4.5 or higher, configured for Rewrite cookie persistence. Failover may not succeed if BIG-IP is set for other persistence settings.
For instructions to configure WebLogic Server for URL rewriting, see “Using URL Rewriting Instead of Cookies” in Developing Web Applications, Servlets, and JSPs for Oracle WebLogic Server.