Overview: Load Balancer (Version 5)

Visit the Edge Component InfoCenter for the documentation library.

Self help information for Edge Components is available on the Technote database from the WebSphere Application Server support Web site.

Related information for WebSphere Application Server products is available from the WebSphere Application Server product library.

For information on how to perform Load Balancer tasks, click How do I? in the navigation area to the left. To find information by keyword, select the Index tab.

Load Balancer is an administration and configuration tool that provides dynamic load balancing, scalability, and high availability for servers on the Internet or on your intranet.

Highlights of Version 5.1.1:

  • Support for additional Linux platforms

    For the most up to date information on supported Linux platforms and all other supported hardware and software for the Edge Components v5.1.1 Fix Pack, access the system requirements Web page for WebSphere Application Server.

  • Mozilla browser requirement on UNIX-based systems

    On UNIX-based systems, the default browser is Mozilla 1.x for viewing helps.

  • Defects fixed --

    To obtain a list of Load Balancer defects fixed for the fix pack, refer to the WebSphere Application Server Web site Support page.

    • From the Support page, enter search term category "Edge Components" and limit results to "Download" then click submit.
    • Follow the link to the corrective service download site to obtain the list of defects fixed for Edge Components.

Highlights of Version 5.1:

  • JDK upgrade requirement

    Load Balancer now supports JDK 1.4.1

Highlights of Version 5.0.2 (Fix Pack 2):

  • Support for s390 Linux (31-bit mode), ppc64 Linux (64-bit mode), Solaris 9 (32-bit or 64-bit mode), and Windows Server 2003

    For the most up to date information on all supported hardware and software access the system requirements Web page for WebSphere Application Server.

  • Load Balancing WebSphere Application Servers

    This feature applies to the CBR component.
    CBR now supports load balancing Web application requests to WebSphere Application Server (version 5) servers using the WebSphere Application Server form of affinity. CBR has the ability to automatically map the HTTP plugin configuration file to a CBR configuration file in order to perform load balancing of your WebSphere Application Server configurations.

Highlights of Version 5.0.1 (Fix Pack 1):

  • Support for HP-UX 11i v1 (32-bit or 64-bit mode) and AIX v5.2 (32-bit or 64-bit mode)
  • For the most up to date information on all supported hardware and software access the system requirements Web page for WebSphere Application Server.

Highlights of Version 5.0:

  • Support for 64-bit mode on AIX and Solaris platforms

    For the most up to date information on all supported hardware and software access the system requirements Web page for WebSphere Application Server.

  • Enhancement to the Cisco CSS Controller component

    The Cisco CSS switch is a hardware-based load balancer with an SNMP interface for fetching connection information and setting weights. The Cisco CSS Controller (formerly known as Cisco Consultant) is a Load Balancer component that monitors servers being load balanced by the Cisco CSS switch and provides appropriate weights to ensure accurate load balancing. The controller enhances the server load-balancing function of the Cisco CSS switch with greater application and system awareness.

  • Nortel Alteon Controller component

    This feature is a new component for Load Balancer.
    The Nortel Alteon Controller is similar to the Cisco CSS Controller delivered in the previous release. The Nortel Alteon Web switch is a hardware-based load balancer with an SNMP interface for fetching connection information and setting weights. The Nortel Alteon Controller is a new Load Balancer component that monitors servers being load balanced by the Alteon switch and provides appropriate weights to ensure accurate load balancing. The controller enhances the server load-balancing function of the Nortel Alteon switch with greater application and system awareness.

  • Controller high availability

    This feature applies to the Cisco CSS Controller and Nortel Alteon Controller components.
    Load Balancer now supports high availability for both the Cisco CSS Controller component and the Nortel Alteon Controller component. With this feature the customer can install the controller in a backup server to take over load balancing functions if the primary server fails.

  • Connections per second rule enhancement

    This feature applies to the Dispatcher and CBR components.
    The enhancement to the connections per second rule allows the customer to specify the "upserversonrule" option on the connections per second rule. By specifying this option, you can ensure that the remaining servers will not be overloaded if one or more servers in the server set goes down.

  • CBR active cookie affinity enhancement

    This feature applies to the CBR component.
    The previous implementation of CBR active cookie affinity based client connections to a server on the cluster and port of the request. This can become a problem in configurations where there are multiple rules with different server sets. The enhancement will allow for multiple affinities within a single cluster and port, allowing a client to maintain affinity with potentially many different servers based on the context of the request.

  • New "heavyweight" HTTPS Advisor

    This feature applies to the Dispatcher, CBR, and Site Selector components.
    In addition to the "lightweight" SSL advisor, support for a "heavyweight" HTTPS advisor has been added. The HTTPS advisor opens full SSL connections which establishes a full SSL socket with the server. (In contrast, the lightweight SSL advisor does not establish a full SSL socket with the server.)

  • Linux SNMP support

    This feature applies to the Dispatcher component.
    Load Balancer now provides SNMP support on Linux platforms. (SNMP support is available on all other platforms supported by Load Balancer.)

  • Remote Web based administration support

    This feature applies to all the components of Load Balancer.
    Load Balancer now supports Remote Web-based administration in addition to remote administration via RMI (remote method invocation).

  • Support for command line access from the GUI

    This feature applies to all the components of Load Balancer.
    A command line ("Send command") can now be accessed from the Host node in the GUI tree.

  • New problem determination tool (lbpd)

    This feature applies to the Dispatcher component.
    For Load Balancer problem determination, a tool (lbpd) has been provided that will quickly and easily gather important information which the customer can send to IBM service.

  • Features removed from the Load Balancer offering
    The following features have been removed from Load Balancer:
    • Mailbox Locator component
    • Server Directed Affinity (SDA)

The five major components of Load Balancer are:

  • Dispatcher - provides load balancing for TCP and UDP applications. Dispatcher balances the load on servers within a local area network or wide area network using several weights and measurements that are dynamically set.

    Content-based routing (without Caching Proxy) is also available on the Dispatcher component to load balance incoming client requests, based on Web page content using specified rule types, to HTTP servers.

  • Content Based Routing (CBR) - works with Caching Proxy to load balance incoming client requests, based on Web page content using specified rule types, to HTTP or HTTPS servers.

  • Site Selector - balances the load on servers within a wide area network (WAN) using measurements and weights that are gathered from the Metric Server component running on those servers.

  • Cisco CSS Controller - uses Load Balancer technology to provide real-time load balancing information to the Cisco Content Services Switch.

  • Nortel Alteon Controller - uses Load Balancer technology to provide server weights dynamically to the Nortel Alteon family of Web switches.