Download - Platform(Domain Creation Activity)
WebLogic Domain
Agenda
• Domain• Overview of Weblogic Server Domain• Admin Server• Managed Server• Resources and Services• Standalone v/s Clustered Managed Servers• Nodemanager• Clusters
Domain
• A domain consists of one or more WebLogic Server instances which are managed by a Admin Server
• A domain can contain:1. Admin Server
2. Managed Server
3. Cluster
4. Resources and Services etc. .
• Modes of Domain Creation are :1. Development Mode2. Production Mode
• Common Domain Types are:
1. Domain with Managed Servers
2. Standalone Server Domain
OVERVIEW OF WEBLOGIC SERVER DOMAINS
Admin Server
Resources and Services
Resources and Services
Resources and Services
Managed Server
Managed Server
Managed Server
Resources and Services
Managed Server
Managed Server
Managed Server
Cluster
ADMIN SERVER•The Administration Server serves as a central location from which to manage and monitor all resources in a domain.•It maintains the domain's configuration documents and distributes changes in the configuration documents to Managed Servers.
Roles of Admin Server:•Act as a central control entity to configure the entire domain. That is, helping in configuring Managed servers, clusters etc..
What happens if Admin Server Fails ?
• Does not affect the operation of Managed Servers in the domain
• Managed Servers and Clusters configured will continue to run
• Load Balancing and Fail Over remains Available
MANAGED SERVERIn a domain, server instances other than the Administration Server are referred to as Managed Servers
Functionality of Managed Server:•Helps in deploying Applications.•One or More Managed servers can be grouped to form clusters.
RESOURCES AND SERVICESA domain contains resources and services needed by Managed Servers and applications deployed in the domain
Examples:Application components, such as Web Applications, J2EE Connectors and Enterprise ApplicationsJDBC connection poolsJMS servers
STANDALONE V/S CLUSTERED MANAGED SERVER
Stand Alone MS Clustered MS
Used in Development Environment Used in Production Environments
No Load Balancing or Fail Over Mechanisms
Load Balancing and Fail Over Mechanisms are present
SERVER LIFE CYCLE
NODEMANAGER• NodeManager is a java utility that allows you to perform
common operations tasks for a managed server.• Runs as a separate process from weblogic server.• Useful in production environments where the weblogic
managed servers are distributed across multiple machines
NODE MANAGER CAPABILITIES
• Node Manager enables you to perform these tasks:
1. Start and stop remote Managed Servers.2. Monitor the self-reported health of Managed Servers
and automatically kill server instances whose health state is "failed".
3. Automatically restart Managed Servers that have the "failed" health state, or have shut down unexpectedly due to a system crash or reboot.
START MANAGED SERVER
SHUTDOWN MANAGED SERVER
Stop a managed server.Shutdown a failed managed server
RESTART MANAGED SERVER
Number of attemptsTime-Span.
WHAT HAPPENS IF THE NODE MANAGER FAILS??
• Do not shut down the managed server which the node manager was monitoring.
• Node manager must be restarted either by the operating system or manually
Flow Diagram of Domain InstallationStartStart
Choose to create new
domain
Choose to create new
domain
Select Product components or
template
Select Product components or
template
Specify username and password for Admin Server
Specify username and password for Admin Server
Select Product components or
template
Select Product components or
template
Customize environments or services ?
Customize environments or services ?
Specify and create domain
Specify and create domain
DoneDone
Customize EnvironmentCustomize Environment
Configure Admin Server
Configure Manage Server, Cluster and machines
Assign Servers to cluster and machines
Customize ServiceCustomize Service
Configure and test DB connectivity
Load DB
Change JMS File StoreYES
Review SettingsReview Settings
No
CLUSTER
CLUSTER
•Multiple Weblogic server instances running simultaneously to provide scalability and reliability•Cluster capacity can be increased dynamically by adding machines to cluster (Same version of Weblogic)
Benefits Of Clustering
• Scalability• High-Availability
Key Capabilities of a Cluster
• Application Failover• Load Balancing
Application Failover
Failover means “an application component doing a particular “job”—some set of processing tasks—becomes unavailable for any reason”
Copy of failed object
Failed Object
Copy
Available?
YES (mandatory)
Information should be made available to all other objects and program that handles failover.Location and operational status of all object
Object taking over an interrupted job knows how much of the job was completed before the first object failed
Picking up from where it had failed
Load Balancing•Load balancing is the even distribution of jobs and associated communications across the computing and networking resources in your environmentFor load balancing to occur:
•There must be multiple copies of an object that can do a particular job.
• Information about the location and operational status of all objects must be available.
Load Balancer
Application Instance 1
Application Instance 2
Application Instance 3