Managing your network: Determining which Load Balancer features to use

This chapter lists the configuration features of the Load Balancer components so you can determine which features to use for managing your network:

Manager, Advisors, and Metric Server functions (for Dispatcher, CBR, and Site Selector components)

To optimize balancing the load across servers and ensure that the "right" server is chosen, see:

Dispatcher component features

Dispatcher supports load balancing across your servers for HTTP, FTP, SSL, SMTP, NNTP, IMAP, POP3, Telnet, SIP, and any other TCP or stateless UDP based application.

Remote administration

Collocation

High availability

Client to server affinity

When load balancing SSL (HTTPS) traffic:

Rules-based load balancing

In order to direct clients to different sets of servers for the same Web address, you can add "rules" to your Dispatcher configuration. For more information, see Configure rules-based load balancing.

Content-based routing using Dispatcher's cbr forwarding method

To ensure SSL clients return to the same SSL server based on SSL ID in the client request, see the section on >configuring content-based routing with SSL.

To direct HTTP clients to different sets of servers using rules based on matching the URL content of the client request, see Dispatcher's content-based routing (cbr forwarding method) and Using rules based on the request content for more information.

Comparison between the Dispatcher component's cbr forwarding method and the CBR component

The advantage of using Dispatcher's cbr forwarding method is that it provides a faster response to client requests than the CBR component. Also, Dispatcher's cbr forwarding does not require the installation and use of Caching Proxy.

If your network includes fully secure SSL (client through server) traffic, the advantage of using the CBR component (in conjunction with Caching Proxy) is that it can process the encryption and decryption required in order to perform content-based routing. For fully secure connections, the Dispatcher's cbr forwarding can only be configured with SSL ID affinity because it cannot process the encryption and decryption to perform true content-based routing on the client request's URL.

Wide area load balancing

Wide area load balancing can be achieved through several different methods.

Port mapping

Setting up Dispatcher on a private network

Wildcard cluster and wildcard port

"Denial of service" attack detection

Binary logging

Alerts

Content Based Routing (CBR) component features

CBR integrates load balancing with WebSphere® Application Server's Caching Proxy to proxy client requests to specified HTTP or HTTPS (SSL) servers. To use CBR, Caching Proxy must be installed and configured on the same machine. For information on how to configure Caching Proxy in order to use CBR, see Step 1. Configure Caching Proxy to use CBR.

Note:
The Content Based Routing (CBR) component is available on all supported platforms except those running a 64-bit JVM. Alternatively, you can use the cbr forwarding method of Load Balancer's Dispatcher component to provide content-based routing without the use of Caching Proxy. See Dispatcher's content-based routing (cbr forwarding method) for more information.

With the CBR component (or the Dispatcher component's cbr forwarding method), you can provide the following advantages to your clients:

Comparison between the CBR component and the Dispatcher component's cbr forwarding method

If your network requires fully secure SSL traffic (client through server), the advantage of using the CBR component (in conjunction with Caching Proxy) is that it can process SSL encryption/decryption in order to perform content-based routing.

For fully secure SSL connections, the Dispatcher's cbr forwarding can only be configured with SSL ID affinity because it cannot process the encryption/decryption to perform true content-based routing on the client request's URL.

For HTTP traffic, the advantage of using Dispatcher's cbr forwarding method is that it provides a faster response to client requests than the CBR component. Also, Dispatcher's cbr forwarding does not require the installation and use of Caching Proxy.

Remote administration

Collocation

CBR with multiple instances of Caching Proxy

Provide content-based routing for SSL connections

To allow content-based routing of SSL traffic:

Server partitioning

Rules-based load balancing

In order to direct clients to different sets of servers for the same Web address, you can add "rules" to your CBR configuration. For more information, see Configure rules-based load balancing.

Client to server affinity

High availability using Dispatcher and CBR

Binary logging

Alerts

Site Selector component features

Site Selector load balances a name service request across a group of servers.

Remote administration

Collocation

High availability

Client to server affinity

Rules-based load balancing

To direct client requests to different sets of servers for domain name resolution, you can add "rules" to your Site Selector configuration. For more information, see Configure rules-based load balancing.

Wide area load balancing

Site Selector can run in both a local area network (LAN) or a wide area network (WAN).

In a WAN environment:

Alerts

Cisco CSS Controller component features

Note:
The Cisco CSS Controller component is shipped with Version 7.0 of Load Balancer for IPv4, but this component might not support newer hardware. Consult the prerequisites page for supported hardware: http://www.ibm.com/support/docview.wss?rs=180&uid=swg27006921

Cisco CSS Controller enhances the Cisco switches' server load-balancing capabilities with greater application and system awareness. The controller uses more application sensitive and system sensitive metrics to calculate server weights dynamically. The weights are provided to the switch using SNMP. The switch uses the weights when processing client requests resulting in server load optimization and improved fault tolerance.

To optimize balancing the load across servers and ensure that the "right" server is chosen, see:

Remote administration

Collocation

High availability

Binary logging

Alerts

Nortel Alteon Controller component features

Note:
The Nortel Alteon Controller component is shipped with Version 7.0 of Load Balancer for IPv4, but this component might not support newer hardware. Consult the prerequisites page for supported hardware: http://www.ibm.com/support/docview.wss?rs=180&uid=swg27006921

Nortel Alteon Controller enhances the Nortel Alteon switches' server load-balancing capabilities with greater application and system awareness. The controller uses more application sensitive and system sensitive metrics to calculate server weights dynamically. The weights are provided to the switch using SNMP. The switch uses the weights when processing client requests resulting in server load optimization and improved fault tolerance.

To optimize balancing the load across servers and ensure that the "right" server is chosen, see:

Remote administration

Collocation

High availability

Binary logging

Alerts