Oracle Weblogic Server 11g: System Administration I
Question No: 61
You use a web browser to log in to a web application that is deployed to WebLogic Server. When you click link named quot;publishquot; on the site, an quot;Access Deniedquot; message appears.
Which two statements must be true about this server#39;s security configuration?
The application is not associated with any security roles.
Multiple security realms are active at the same time.
Your user account is a member of a group.
Your user account exists in an authentication provider.
A security policy is attached to the quot;publishquot; link URL.
Explanation: D: You were able to log in to the web application that is deployed through WebLogic.
In WebLogic Server, Authentication providers are used to prove the identity of users or system processes.
This implies that your account exists in an authentication provider.
E: Extra security is needed to use the publish link. This could be explained by a security policy attached the publish Link URL.
Reference: Developing Security Providers for WebLogic Server, Authentication Providers
Question No: 62
You have set Server log Rotation criteria to either size or time. When a domain is in Production Mode, which statement is true?
Log files are rotated when the server restarts.
Log files are not rotated in Production Mode.
Log files are rotated only when the rotation criteria are met.
Log files are rotated when the rotation criteria are met or rotated when the server restarts
Explanation: By default, when you start a server instance in production mode, the server rotates its local log file whenever the file grows to 5000 kilobytes in size. It does not rotate the local server log file when you start the server.
You can change these default settings for log file rotation. For example, you can change the file size at which the server rotates the log file or you can configure a server to rotate log files based on a time interval. You can also specify the maximum number of rotated files that can accumulate. After the number of log files reaches this number, subsequent file rotations delete the oldest log file and create a new log file with the latest suffix.
Question No: 63
Which three methods does WebLogic provide to implement persistent JMS messaging?
Create a file store and assign it to a JMS server.
Create a JDBC store and assign it to a JMS server.
Configure a file store within a JMS module.
Configure the domain#39;s default store.
Use the target server#39;s default store.
Explanation: A: The main steps for creating a custom file store are as follows:
Create a directory where the file store’s data will be persisted.
Create a custom file store and specify the directory location that you created. 3.Associate the custom file store with the subsystem(s) or migratable target that will be accessing it, such as:
*For JMS servers, select the custom file store on the General Configuration page.
*For Store-and-Forward agents, select the custom file store on the General Configuration page.
*For a Path Service, select the custom file store on the General Configuration page. B: The main steps for creating a JDBC store are as follows:
Create a JDBC data source or multi data source to interface with the JDBC store. Create a JDBC store and associate it with the JDBC data source or multi data source. It is highly recommended that you configure the Prefix option to a unique value for each configured JDBC store table.
Associate the JDBC store with the subsystem(s) that will be using it, such as: For JMS servers, select the JDBC store on the General Configuration page.
For Store-and-Forward agents, select the JDBC store on the General Configuration page. For a Path Service, select the custom file store on the General Configuration page.
E: Each server instance, including the administration server, has a default persistent store that requires no configuration.
When a persistent message is sent, it is stored in the WebLogic Persistent Store.
The persistent store provides a built-in, high-performance storage solution for WebLogic Server subsystems and services that require persistence. For example, it can store persistent JMS messages or temporarily store messages sent using the Store-and-Forward feature. The persistent store supports persistence to a file-based store or to a JDBC- enabled database.
Note 2: A persistent message is guaranteed to be delivered once-and-only-once. The message cannot be lost due to a JMS provider failure and it must not be delivered twice. It is not considered sent until it has been safely written to a file or database. WebLogic JMS writes persistent messages to a WebLogic persistent store (disk-base file or JDBC- accessible database) that is optionally targeted by each JMS server during configuration.
Reference: Using the WebLogic Persistent Store
Question No: 64
Managed Server Independence enabled is not selected in the configuration of myserver1. Which statement is true?
Only the Node Manager can start myserver1
Only a local start script can start myserver1
Myserver1 cannot be part of a cluster.
The Administration Server must be available before starting myserver1
Explanation: To prevent the Administration Server from becoming a single point of failure, Managed Servers can always function without the presence a running Administration Server. When a Managed Server starts, it contacts the Administration Server to retrieve its configuration information. If a Managed Server is unable to connect to the specified Administration Server during startup, it can retrieve its configuration directly by reading a copy of the config.xml file and other files located on the Managed Server#39;s own file system. A Managed Server that starts in this way is running in Managed Server Independence mode. In this mode, a server uses cached application files to deploy the applications that are targeted to the server.
Reference: Overview of WebLogic Server System Administration, Managed Server Indepenence
Question No: 65
You have opened a terminal window (or a Window command prompt) to run a WLST script named weeklydeployer.py. You enter the following command:
Java weblogic.WLST weeklydeployer.py
Instead of the WLST initializing and the script running, however, you receive the NoClassDefFoundError java exception for weblogic/WLST.
What is the problem?
You forgot to set PATH to include the java executable.
There is an error in the code of the script.
You forgot to set CLASSPATH to include weblogic.jar.
You are not in the directory where weeklydeployer.py resides.
You should have omitted the quot;.pyquot; in the file name; it is assumed by WLST.
You forgot to set PATH to include the WLST executable.
Explanation: To set up your environment for WLST:
Install and configure the WebLogic Server software
Add WebLogic Server classes to the CLASSPATH environment variable
Note: Although the process should be able to build the correct classpath by default, you might hit this issue in some cases. To overcome the problem, you must explicitly set the classpath in the admin console accordingly.
Reference: WebLogic Scripting Tool, Using the WebLogic Scripting Tool
Question No: 66
You monitor a running JMS topic with the console and note the following values:
Consumers Current = 3 Message Current = 1 Message Pending = 0
These values do not change for several minutes. Which is the most plausible explanation?
Production on the topic has been paused.
A message arrived after a durable subscribe disconnected from the topic.
One of the consumers received a message but did not acknowledge it.
None of the consumers are durable subscribes.
Explanation: For durable subscriptions, WebLogic JMS stores a message in a persistent file or database until the message has been delivered to the subscribers or has expired, even if those subscribers are not active at the time that the message is delivered.
Note #1: Durable subscriptions means that weblogic server will store the messages in a persistent store (i.e a file-store or a JDBC-store) until those messages are delivered to the subscribers/listener. This technic helps weblogic server to make sure that the messages get delivered even if those subscribers/listeners are not active at the time that the message is getting delivered.
As all of us know that in Topic’s the senders/producers just send the messages to the topic and the receivers/listeners have subscribe them self to get those messages, hence senders/producers does not have any concern if the messages are been received or not.
However with this feature weblogic make sure all the subscribers would get the messages as the messages gets stored in a persistence store.
Consumers Current Count: Current number of consumers accessing this destination
MessagesCurrentCount: The current number of messages in the destination. This does not include the pending messages.
MessagesPendingCount: The number of pending messages in the destination.
Pending messages are over and above the current number of messages. A pending message is one that has either been sent in a transaction and not committed, or that has been received and not committed or acknowledged.
Reference: eDocs Home gt; BEA WebLogic Server 8.1 Documentation gt; Programming WebLogic JMS gt; Developing a WebLogic JMS Application, Setting Up Durable Subscriptions
Question No: 67
Which statement best describes WebLog’s default application staging behavior?
The Administration Sever distributes application files when the application is first accessed by a client.
The Administration Sever copied application files to a database that is shared with the Managed Servers.
The Managed Servers obtain application files from a disk that is shared with the Administration Server.
The Administration Sever distributes copied of application files over the network to the Managed Servers.
Explanation: Deployment Staging Mode: stage
Behavior: The Administration Server first copies the deployment unit source files to the staging directories of target servers specified by the Staging Directory Name attribute.
The target servers then deploy using their local copy of the deployment files.
Note: The deployment staging mode determines how deployment files are made available to target servers that must deploy an application or standalone module. WebLogic Server provides three different options for staging files: stage mode, nostage mode, and external_stage mode. The following table describes the behavior and best practices for using the different deployment staging modes.
Reference: Overview of WebLogic Server Deployment, Staging Modes
Question No: 68
Indentify two valid elements that can belong in the weblogic-application.xml deployment descriptor.
Explanation: B: lt;library-refgt;
A reference to a shared Java EE library. Enclose all other elements within library-ref.
Note: A Java EE application can reference a registered shared Java EE library using entries in the application’s weblogic-application.xml deployment descriptor.
Elements include: library-ref
Specifies the Work Manager that is associated with the application.
Note: The weblogic-application.xml file is the BEA WebLogic Server-specific deployment descriptor extension for the application.xml deployment descriptor from Sun Microsystems. This is where you configure features such as shared Java EE libraries referenced in the application and EJB caching.
The file is located in the META-INF subdirectory of the application archive.
Reference: Developing Applications With WebLogic Server. weblogic-application.xml Deployment Descriptor Elements
Reference: Referencing Shared Java EE Libraries in an Enterprise Application
Question No: 69
You create a system-wide JMS module named Payroll-JMS and set its default target to an existing cluster in your domain named PayrollCluster. Next, you add a standard JMS topic
to Payroll-JMS. To which are you permitted to target this topic?
the entire PayrollCluster
any single JMS server in the domain
any combination of member servers in Payrollcluster
several JMS servers targeted to PayrollCluster
Explanation: JMS system modules are owned by the Administrator, who can delete, modify, or add JMS system resources at any time. With the exception of standalone queue and topic resources that must be targeted to a single JMS server, the connection factory, distributed destination, foreign server, and JMS SAF destination resources in system modules can be made globally available by targeting them to server instances and clusters configured in the WebLogic domain. These resources are therefore available to all applications deployed on the same targets and to client applications.
Note #1: JMS modules are application-related definitions that are independent of the domain environment. You create and manage JMS resources either as system modules or as application modules.
System modules are globally available for targeting to servers and clusters configured in the domain, and therefore are available to all applications deployed on the same targets and to client applications.
Note #2: JMS servers are environment-related configuration entities that act as management containers for the queues and topics in JMS modules that are targeted to them. A JMS server#39;s primary responsibility for its destinations is to maintain information on what persistent store is used for any persistent messages that arrive on the destinations, and to maintain the states of durable subscribers created on the destinations. JMS servers also manage message paging on destinations, and, optionally, can manage message and/or byte thresholds, as well as server-level quota for its targeted destinations. As a container for targeted destinations, any configuration or run-time changes to a JMS server can affect all the destinations that it hosts.
Question No: 70
The project’s architect has provided you with a design diagram that identifies the key components of the new insurance system. From the diagram, you can clearly see that JMS will be used as the communication channel between several applications. Identify four tasks that you may need to perform to support this design.
Create a JMS server
Create a JMS message template
Add JMS destinations to a JMS module
Add a JMS module to a JMS factory
Target JMS destinations to JMS servers
Target a JMS server to a WebLogic Server
Target a JMS module to a JMS store
Answer: A,C,E,F Explanation:
A: If necessary, create a JMS server to target the JMS module.
F: Target the JMS Server to a weblogic server
Note: The major components of the WebLogic JMS Server architecture:
JMS servers that can host a defined set of modules and any associated persistent storage that reside on a WebLogic Server instance.
JMS modules contains configuration resources (such as queues, topics, and connections factories) and are defined by XML documents that conform to the weblogic-jms.xsd schema.
Client JMS applications that either produce messages to destinations or consume messages from destinations.
JNDI (Java Naming and Directory Interface), which provides a resource lookup facility. JMS resources such as connection factories and destinations are configured with a JNDI name. The runtime implementations of these resources are then bound into JNDI using the given names.
WebLogic persistent storage (file store or JDBC-accessible) for storing persistent message data.
Reference: Understanding WebLogic JMS