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Title and Copyright Information

Preface

• Documentation Accessibility
• Conventions

1 Introduction and Roadmap

• Document Scope and Audience
• Guide to this Document
• Related Documentation
• New and Changed Clustering Features in This Release

2 Understanding WebLogic Server Clustering

• What Is a WebLogic Server Cluster?
• How Does a Cluster Relate to a Domain?
• What Are the Benefits of Clustering?
• What Are the Key Capabilities of a Cluster?
• What Types of Objects Can Be Clustered?
  • Servlets and JSPs
  • EJBs and RMI Objects
  • JDBC Connections
    • Getting Connections with Clustered JDBC
    • Failover and Load Balancing for JDBC Connections
  • JMS and Clustering
• What Types of Objects Cannot Be Clustered?

3 Communications In a Cluster

• WebLogic Server Communication In a Cluster
  • Using IP Multicast for Backward Compatibility
    • Multicast and Cluster Configuration
  • One-to-Many Communication Using Unicast
    • Unicast Configuration
    • Considerations When Using Unicast
  • 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
  • How WebLogic Server Creates the Cluster-Wide JNDI Tree
  • How JNDI Naming Conflicts Occur
    • Deploy Homogeneously to Avoid Cluster-Level JNDI Conflicts
  • How WebLogic Server Updates the JNDI Tree
  • Client Interaction with the Cluster-Wide JNDI Tree

4 Understanding Cluster Configuration

• Cluster Configuration and config.xml
• Role of the Administration Server
• What Happens if the Administration Server Fails?
• How Dynamic Configuration Works
• Application Deployment for Clustered Configurations
• Deployment Methods
• Introduction to Two-Phase Deployment
• First Phase of Deployment
• Second Phase of Deployment
• Guidelines for Deploying to a Cluster
• WebLogic Server Supports "Relaxed Deployment" Rules
  • Deployment to a Partial Cluster is Allowed
  • Deploying to Complete Clusters in WebLogic Server
  • Pinned Services can be Deployed to Multiple Managed Servers.
• Methods of Configuring Clusters

5 Load Balancing in a Cluster

• Load Balancing for Servlets and JSPs
• Load Balancing with a Proxy Plug-in
  • How Session Connection and Failover Work with a Proxy Plug-in
• Load Balancing HTTP Sessions with an External Load Balancer
  • Load Balancer Configuration Requirements
  • Load Balancers and the WebLogic Session Cookie
  • Related Programming Considerations
  • How Session Connection and Failover Works with a Load Balancer
• Load Balancing for EJBs and RMI Objects
• Round Robin Load Balancing
• Weight-Based Load Balancing
• Random Load Balancing
• Server Affinity Load Balancing Algorithms
  • Server Affinity and Initial Context
  • Server Affinity and IIOP Client Authentication Using CSIv2
  • Round-Robin Affinity, Weight-Based Affinity, and Random-Affinity
    • Server Affinity Examples
• Parameter-Based Routing for Clustered Objects
• Optimization for Collocated Objects
  • Transactional Collocation
• Load Balancing for JMS
• Server Affinity for Distributed JMS Destinations
• Initial Context Affinity and Server Affinity for Client Connections
• Load Balancing for JDBC Connections

6 Failover and Replication in a Cluster

• How WebLogic Server Detects Failures
• Failure Detection Using IP Sockets
• The WebLogic Server "Heartbeat"
• Replication and Failover for Servlets and JSPs
• HTTP Session State Replication
  • Requirements for HTTP Session State Replication
    • Supported Server and Proxy Software
    • Load Balancer Requirements
    • Programming Considerations for Clustered Servlets and JSPs
  • Using Replication Groups
• Accessing Clustered Servlets and JSPs Using a Proxy
  • Proxy Connection Procedure
    • Using URL Rewriting to Track Session Replicas
  • Proxy Failover Procedure
• Accessing Clustered Servlets and JSPs with Load Balancing Hardware
  • Connection with Load Balancing Hardware
  • Failover with Load Balancing Hardware
• Session State Replication Across Clusters in a MAN/WAN
  • Network Requirements for Cross-cluster Replication
    • Global Load Balancer
    • Local Load Balancer
    • Replication
    • Failover
  • Configuration Requirements for Cross-Cluster Replication
  • Configuring Session State Replication Across Clusters
  • Configuring a Replication Channel
  • MAN HTTP Session State Replication
    • Replication Within a MAN
    • Failover Scenarios in a MAN
    • MAN Replication, Load Balancers, and Session Stickiness
  • WAN HTTP Session State Replication
    • Replication Within a WAN
    • Failover Scenarios Within a WAN
    • Database Configuration for WAN Session State Replication
• Replication and Failover for EJBs and RMIs
• Clustering Objects with Replica-Aware Stubs
• Clustering Support for Different Types of EJBs
  • Clustered EJBHomes
  • Clustered EJBObjects
    • Stateless Session Beans
    • Stateful Session Beans
    • Failover for Stateful Session EJBs
  • Entity EJBs
    • Failover for Entity Beans and EJB Handles
• Clustering Support for RMI Objects
• Object Deployment Requirements
  • Other Failover Exceptions
• Failover and JDBC Connections

7 Whole Server Migration

• Understanding Server and Service Migration
• Migration Terminology
• Leasing
• Features That Use Leasing
• Leasing Versions
• Determining Which Type of Leasing To Use
• High-availability Database Leasing
• Non-database Consensus Leasing
• Automatic Whole Server Migration
• Preparing for Automatic Whole Server Migration
• Configuring Automatic Whole Server Migration
• Using High Availability Storage for State Data
• Server Migration Processes and Communications
  • Startup Process in a Cluster with Migratable Servers
  • Automatic Whole Server Migration Process
  • Manual Whole Server Migration Process
  • Administration Server's Role in Whole Server Migration
  • Migratable Server Behavior in a Cluster
  • Node Manager's Role in Whole Server Migration
  • Cluster Master's Role in Whole Server Migration

8 Service Migration

• Understanding the Service Migration Framework
• Migratable Services
  • JMS-related Services
  • JTA Transaction Recovery Service
  • User-defined Singleton Services
• Understanding Migratable Targets In a Cluster
  • Policies for Manual and Automatic Service Migration
    • Manual Migration
    • Exactly-Once
    • Failure-Recovery
  • Options For Attempting to Restart Failed Services Before Migrating
  • User-Preferred Servers and Candidate Servers
  • Example Migratable Targets In a Cluster
  • Targeting Rules for JMS Servers
  • Targeting Rules for SAF Agents
    • Re-targeting SAF Agents to Migratable Targets
    • Targeting Migratable SAF Agents For Increased Message Throughput
    • Targeting SAF Agents For Consistent Quality-of-Service
  • Targeting Rules for Path Service
    • Special Considerations For Targeting a Path Service
  • Targeting Rules for Custom Stores
  • Migratable Targets For the JTA Transaction Recovery Service
• Migration Processing Tools
  • Administration Console
  • WebLogic Scripting Tool
• Automatic Service Migration Infrastructure
  • Leasing for Migratable Services
    • Database Leasing
    • Consensus Leasing
    • Node Manager
  • Administration Server Not Required When Migrating Services
  • Service Health Monitoring
    • How Health Monitoring of the JTA Transaction Recovery Service Triggers Automatic Migration
    • How Health Monitoring of JMS-related Services Triggers Automatic Migration
• In-Place Restarting of Failed Migratable Services
• Migrating a Service From an Unavailable Server
• JMS and JTA Automatic Service Migration Interaction
• Pre-Migration Requirements
• Custom Store Availability for JMS Services
• Default File Store Availability for JTA
• Server State and Manual Service Migration
• Roadmap for Configuring Automatic Migration of JMS-related Services
• Step 1: Configured Managed Servers and Node Manager
• Step 2: Configure the Migration Leasing Basis
• Step 3: Configure Migratable Targets
  • Configuring a Migratable Server As an Automatically Migratable Target
  • Create a New Migratable Target
    • Select a User Preferred Server
    • Select a Service Migration Policy
    • Optionally Select Constrained Candidate Servers
    • Optionally Specify Pre/Post-Migration Scripts
    • Optionally Specify In-Place Restart Options
• Step 4: Configure and Target Custom Stores
• Step 5: Target the JMS Services
  • Special Considerations When Targeting SAF Agents or Path Service
• Step 6: Restart the Administration Server and Managed Servers With Modified Migration Policies
• Step 7: Manually Migrating JMS Services Back to the Original Server
• Best Practices for Targeting JMS when Configuring Automatic Service Migration
• Roadmap for Configuring Manual Migration of JMS-related Services
• Step 1: Configured Managed Servers
• Step 2: Configure Migratable Targets
  • Configuring a Migratable Server As a Migratable Target
  • Create a New Migratable Target
    • Select a Preferred Server
    • Accept the Default Manual Service Migration Policy
    • Optionally Select Constrained Candidate Servers
    • Optionally Specify Pre/Post-Migration Scripts
    • Optionally Specify In-Place Restart Options
• Step 3: Configure and Target Custom Stores
• Step 4: Target the JMS Services
  • Special Considerations When Targeting SAF Agents or Path Service
• Step 5: Restart the Administration Server and Managed Servers With Modified Migration Policies
• Step 6: Manually Migrating JMS Services
• Roadmap for Configuring Automatic Migration of the JTA Transaction Recovery Service
• Step 1: Configured Managed Servers and Node Manager
• Step 2: Configure the Migration Basis
• Step 3: Enable Automatic JTA Migration
  • Select the Automatic JTA Migration Check Box
  • Optionally Select Candidate Servers
  • Optionally Specify Pre/Post-Migration Scripts
• Step 4: Configure the Default Persistent Store For Transaction Recovery Service Migration
• Step 5: Restart the Administration Server and Managed Servers With Modified Migration Policies
• Step 6: Automatic Failback of the Transaction Recovery Service Back to the Original Server
• Manual Migration of the JTA Transaction Recovery Service
• Automatic Migration of User-Defined Singleton Services
• Overview of Singleton Service Migration
  • Singleton Master
  • Migration Failure
• Implementing the Singleton Service Interface
• Deploying a Singleton Service and Configuring the Migration Behavior
  • Packaging and Deploying a Singleton Service Within an Application
  • Deploying a Singleton Service As a Standalone Service in WebLogic Server
  • Configuring Singleton Service Migration

9 Cluster Architectures

• Architectural and Cluster Terminology
• Architecture
• Web Application Tiers
• Combined Tier Architecture
• De-Militarized Zone (DMZ)
• Load Balancer
• Proxy Plug-In
• Recommended Basic Architecture
• When Not to Use a Combined Tier Architecture
• Recommended Multi-Tier Architecture
• Physical Hardware and Software Layers
  • Web/Presentation Layer
  • Object Layer
• Benefits of Multi-Tier Architecture
• Load Balancing Clustered Objects in a in Multi-Tier Architecture
• Configuration Considerations for Multi-Tier Architecture
  • IP Socket Usage
  • Hardware Load Balancers
• Limitations of Multi-Tier Architectures
  • No Collocation Optimization
  • Firewall Restrictions
• Recommended Proxy Architectures
• Two-Tier Proxy Architecture
  • Physical Hardware and Software Layers
    • Web Layer
    • Servlet/Object Layer
• Multi-Tier Proxy Architecture
• Proxy Architecture Benefits
• Proxy Architecture Limitations
• Proxy Plug-In Versus Load Balancer
• Security Options for Cluster Architectures
• Basic Firewall for Proxy Architectures
  • Firewall Between Proxy Layer and Cluster
  • 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

10 Setting up WebLogic Clusters

• Before You Start
• 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
  • Setting Up a Cluster on a Disconnected Windows Machine
• Identify Names and Addresses
  • Avoiding Listen Address Problems
    • DNS Names or IP Addresses?
    • When Internal and External DNS Names Vary
    • Localhost Considerations
  • Assigning Names to WebLogic Server Resources
  • Administration Server Address and Port
  • Managed Server Addresses and Listen Ports
  • Cluster Multicast Address and Port
    • Multicast and Multiple Clusters
    • Multicast and Multi-Tier Clusters
  • Cluster Address
    • Dynamic Cluster Address
    • Explicitly Defining Cluster Address for Production Environments
    • Explicitly Defining Cluster Address for Development and Test Environments
    • Explicitly Defining Cluster Address for Single, Multihomed Machine
• Cluster Implementation Procedures
• Configuration Roadmap
• Install WebLogic Server
• Create a Clustered Domain
  • Starting a WebLogic Server Cluster
• Configure Node Manager
• Configure Load Balancing Method for EJBs and RMIs
• Specifying a Timeout Value For RMIs
• Configure Server Affinity for Distributed JMS Destinations
• Configuring Load Balancers that Support Passive Cookie Persistence
• Configure Proxy Plug-Ins
  • Set Up the HttpClusterServlet
    • Sample web.xml
    • Sample weblogic.xml
    • Proxy Servlet Deployment Parameters
    • Accessing Applications Via the Proxy Server
• Configure Replication Groups
• Configure Migratable Targets for Pinned Services
• Configure Clustered JDBC
  • Clustering Data Sources
• Clustering Multi Data Sources
• Package Applications for Deployment
• Deploy Applications
  • Deploying to a Single Server Instance (Pinned Deployment)
    • Pinned Deployment from the Command Line
  • Cancelling Cluster Deployments
    • Cancel Deployment from the Command Line
    • Cancel Deployment Using the Administration Console
  • Viewing Deployed Applications
  • Undeploying Deployed Applications
• Deploying, Activating, and Migrating Migratable Services
  • Deploying JMS to a Migratable Target Server Instance
  • Activating JTA as a Migratable Service
  • Migrating a Pinned Service to a Target Server Instance
    • Migrating When the Currently Active Host is Unavailable
• Configure In-Memory HTTP Replication
• Additional Configuration Topics
  • Configure IP Sockets
    • Configure Native IP Sockets Readers on Machines that Host Server Instances
    • Set the Number of Reader Threads on Machines that Host Server Instances
    • Set the Number of Reader Threads on Client Machines
  • Configure Multicast Time-To-Live (TTL)
  • Configure Multicast Buffer Size
  • Configure Multicast Data Encryption
  • Configure Machine Names
  • Configuration Notes for Multi-Tier Architecture
  • Enable URL Rewriting

11 Clustering Best Practices

• General Design Considerations
• Strive for Simplicity
• Minimize Remote Calls
  • Session Facades Reduce Remote Calls
  • Transfer Objects Reduce Remote Calls
  • Distributed Transactions Increase Remote Calls
• Web Application Design Considerations
• Configure In-Memory Replication
• Design for Idempotence
• Programming Considerations
• EJB Design Considerations
• Design Idempotent Methods
• Follow Usage and Configuration Guidelines
  • Cluster-Related Configuration Options
• State Management in a Cluster
• Application Deployment Considerations
• Architecture Considerations
• Avoiding Problems
• Naming Considerations
• Administration Server Considerations
• Firewall Considerations
• Evaluate Cluster Capacity Prior to Production Use

12 Troubleshooting Common Problems

• Before You Start the Cluster
• Check the Server Version Numbers
• Check the Multicast Address
• Check the CLASSPATH Value
• Check the Thread Count
• After You Start the Cluster
  • Check Your Commands
  • Generate a Log File
  • Getting a JRockit Thread Dump Under Linux
• Check Garbage Collection
• Run utils.MulticastTest

13 Troubleshooting Multicast Configuration

• Verifying Multicast Address and Port Configuration
  • Possible Errors
  • Checking the Multicast Address and Port
• Identifying Network Configuration Problems
  • Physical Connections
  • Address Conflicts
  • nsswitch.conf Settings on UNIX Systems
• Using the MulticastTest Utility
• Tuning Multicast Features
  • Multicast Timeouts
  • Cluster Heartbeats
    • Multicast Send Delay
    • Operating System Parameters
  • Multicast Storms
  • Multicast and Multihomed Machines
  • Multicast in Different Subnets
• Debugging Multicast
  • Debugging Utilities
    • MulticastMonitor
    • MulticastTest
  • Debugging Flags
    • Setting Debug Flags on the Command Line
    • Setting Debug Flags by Using weblogic.Admin
• Miscellaneous Issues
  • Multicast on AIX
  • File Descriptor Problems
• Other Resources for Troubleshooting Multicast Configuration

A The WebLogic Cluster API

• How to Use the API
• Custom Call Routing and Collocation Optimization

B Configuring BIG-IP Hardware with Clusters

• Configuring Session Persistence
• Configuring URL Rewriting
• Configuring WebLogic Server for URL Rewriting
• Configuring BIG-IP for URL Rewriting

C Configuring F5 Load Balancers for MAN/WAN Failover

• Requirements
• Configure Local Load Balancers
• Virtual Server IPs and Pools
• Create a Failover Trigger Virtual Server and Pool
• Create a Multi-layered Virtual Server and IP Pool
• Configure the 3-DNS Global Hardware Load Balancer
• Configure DNS Zones
• Configure BIG-IP Addresses Managed by 3-DNS
• Configure Data Centers
• Configure Wide IPs
• Configuring WebLogic Server Components

D Configuring Radware Load Balancers for MAN/WAN Failover

• Requirements
• Step 1: Configure an Authoritative Delegation Zone
• Step 2: Configure Farm Virtual IPs and Servers
• Create a Farm IP
• Configure the Dispatch Method for the Server Farm
• Creating Farm Servers
• Step 3: Configure Port Multiplexing
• Step 4: Configure HTTP Redirects
• Step 5: Configure Session ID Persistency
• Step 6: Configure LRP
• Step 7: Configure WebLogic Server Components