Using WebLogic Server Clusters

 

 

Introduction to WebLogic Server Clustering

What Is a WebLogic Server Cluster?

What Services Are Clustered?

HTTP Session States

EJBs and RMI objects

JMS

JDBC Connections

Getting Connections with Clustered JDBC

Failover and Load Balancing for JDBC Connections

Non-Clustered Services and APIs

New Cluster Features in WebLogic Server Version 6.1

Integrated Support for Load Balancing Hardware

Stateful Session EJB Clustering

Clustered JMS

HTTP Session State Replication Changes

Administration Changes in WebLogic Server Version 6.1

Multicast Message Changes

Homogeneous Deployment

Administration Server Configuration

 

Cluster Features and Infrastructure

Overview

Server Communication in a Cluster

One-to-Many Communication Using IP Multicast

Implications for Cluster Planning and Configuration

Peer-to-Peer Communication Using IP Sockets

Pure-Java Versus Native Socket Reader Implementations

Configuring Reader Threads for Java Socket Implementation

Client Communication via Sockets

Cluster-Wide JNDI Naming Service

Creating the Cluster-Wide JNDI Tree

Handling JNDI Naming Conflicts

Homogeneous Deployment

Updating the JNDI Tree

Client Interaction with the Cluster-Wide JNDI Tree

Load Balancing of Clustered Services

Load Balancing for HTTP Session States

Load Balancing for Clustered Objects

Round-Robin (Default)

Weight-Based

Random

Using Parameter-Based Routing for Clustered Objects

Load Balancing and JDBC Connections

Load Balancing and JMS

Failover Support for Clustered Services

How WebLogic Server Detects Failures

Failure Detection Using IP Sockets

The WebLogic Server "Heartbeat"

Failover for Clustered Servlets and JSPs

Failover for Clustered Objects

Idempotent Objects

Other Failover Exceptions

Failover and JDBC Connections

Failover and JMS

 

Understanding HTTP Session State Replication

Overview

Requirements for HTTP Session State Replication

Proxy Requirements

Load Balancer Requirements

Session Programming Requirements

Session Data Must Be Serializable

Use setAttribute to Change Session State

Consider Serialization Overhead for Session Objects

Applications Using Frames Must Coordinate Session Access

Using Replication Groups

Accessing Clustered Servlets and JSPs Using a Proxy

Using URL Rewriting to Track Session Replicas

Proxy Failover Procedure

Accessing Clustered Servlets and JSPs with Load Balancing Hardware

Failover with Load Balancing Hardware

Delayed Replication after a Failure

 

Understanding Object Clustering

Overview

Replica-Aware Stubs

Clustered Objects and RMI-IIOP Clients

Clustered EJBs

EJB Home Stubs

Stateless EJBs

Stateful EJBs

Entity EJBs

Failover for Entity Beans and EJB Handles

Clustered RMI Objects

Stateful Session Bean Replication

Replicating EJB State Changes

Failover for Stateful Session EJBs

Optimization for Collocated Objects

Transactional Collocation

Object Deployment Requirements

 

Planning WebLogic Server Clusters

Overview

Capacity Planning

WebLogic Servers on Multi-CPU machines

Definition of Terms

Web Application "Tiers"

De-Militarized Zone (DMZ)

Load Balancer

Proxy Plug-In

Recommended Basic Cluster

Planning by Dividing Application Tiers

Recommended Multi-Tier Architecture

Physical Hardware and Software Layers

Web/Presentation Layer

Object Layer

Benefits of Multi-Tier Architecture

Load Balancing for Clustered Object Calls

Configuration Notes for Multi-Tier Architecture

Limitations of Multi-Tier Architecture

Firewall Restrictions

Recommended Proxy Architectures

Two-Tier Proxy Architecture

Physical Hardware and Software Layers

Multi-Tier Proxy Architecture

Proxy Architecture Trade-Offs

Proxy Plug-In Versus Load Balancer

Administration Server Considerations

What Happens if the Administration Server Fails?

Security Options for Cluster Architectures

Basic Firewall for Proxy Architectures

DMZ with Basic Firewall Configurations

Combining Firewall with Load Balancer

Expanding the Firewall for Internal Clients

Additional Security for Shared Databases

DMZ with Two Firewall Configuration

Firewall Considerations for Clusters

 

Administering WebLogic Clusters

Before You Start

Obtain a Cluster Licence

Understand the Configuration Process

Determine Your Cluster Architecture

Consider Your Network and Security Topologies

Choose Machines for the Cluster Installation

WebLogic Server Instances on Multi-CPU machines

Check Host Machines' Socket Reader Implementation

Identify Names and Addresses

Avoiding Listen Address Problems

Assigning Names to WebLogic Server Resources

Administration Server Address and Port

Managed Server Addresses and Listen Ports

Cluster Multicast Address and Port

Cluster Address

Cluster Implementation Procedures

Configuration Roadmap

Install WebLogic Server

Define Machine Names (Optional)

Create WebLogic Server Instances

Create a New Cluster

Starting a WebLogic Server Cluster

Configure Load Balancing Hardware (Optional)

Using Active Cookie Persistence

Using Passive Cookie Persistence

Configure Proxy Plug-Ins (Optional)

Configure Replication Groups (Optional)

Configure Clustered JDBC

Clustering Connection Pools

Clustering Multipools

Configure JMS

Configure In-Memory HTTP Replication

Deploy Web Applications and EJBs

Additional Configuration Topics

Configure IP Sockets

Configure Multicast Time-To-Live (TTL)

Configure Multicast Buffer Size

Configuration Notes for Multi-Tier Architecture

Enable URL Rewriting

 

Troubleshooting Common Problems

Collecting Diagnostic Information

Getting a JRockit Thread Dump Under Linux

Providing Diagnostics to BEA Technical Support

Addressing Common Problems

Server Fails to Join a Cluster

 

The WebLogic Cluster API

How to Use the API

Custom Call Routing and Collocation Optimization

 

Configuring BIG-IP^TM Hardware with Clusters

Overview

Using URL Rewriting With BIG-IP and WebLogic Server

Using Session Persistence with BIG-IP and WebLogic Server