Tuesday, April 28, 2009

Load Balancer Config

Yesterday I discussed about Overview of Load balancer and various types of load balancer as you can configure load balancer at various levels like
- DNS Layer Load balancing
- HTTP Server level Hardware Load balancing(Discussed today)
- Jserv level load balancing (I'll discuss after HTTP level load balancing)

Today in this post I am discussing only at HTTP Server level Hardware Load balancer.
Before configuring Load balancer in Oracle Apps , you should be familiar with following technologies
1. Cloning
Check my previous post to know about cloning
Cloning Basics
Cloning Part I
Cloning Part II
Metalink Note # 230672.1 Cloning Oracle Applications Release 11i with Rapid Clone
2. Load Balancer Basics
Check my previous post for Over of Load balancer
Load Balancer Overview
3. Autoconfig
Check About Autoconfig on My Site
Metalink Note 165195.1 Using AutoConfig to Manage System Configurations with Oracle Applications 11i

Broad Level steps for configuring Hardware Load balancer at HTTP Server layer
A. Configure Hardware Load Balancer for Session Persistence
B. Apply Prereq. Patch (If you are not on 11.5.10 or higher)
C. Add additional Web Node using Rapid Clone
D. Configure Load balancer on Node1
E. Test Load balancer via Node1
F. Configure Load balancer on Node2
G. Test Load balancer via Node2
H. Test Load balancer is sending requests to both nodes when both Web Nodes are Up

Yesterday I posted that you need extra attention while configuring Load balancer at HTTP layer is about
Session Persistence - Hardware level Load Balancer should be configured for session persistence also called as stickness or sticky bit for Oracle Apps 11i . If this is not set & lets assume client1 first request went to Node1 after authentication if next request for client1 goes to Node2 who is not aware of client1 's previous request will throw authentication again. Don't worry about how to set it, ask vendor or Unix Administrator to set sticky bit or session persistence .

Now you have broad overview of configuring Load balancer at HTTP layer, I'll discuss in detail why you need to apply above patches & what all step by step configuration and parameters which needs to be changed and reasoning behind those changes . Till then check for Cloning, Autoconfig.

No comments:

Post a Comment