1Z0-599 Online Practice Questions and Answers

Correct Answer: A

XA Affinity and Failover When accessed within a global transaction, the member data source from which the JDBC connection was obtained is pinned to the global transaction for the life of the transaction. This ensures that all database operations performed on connections obtained from the Multi Data Source, for a particular transaction, all execute on the same RAC instance. XA affinity results in improved performance and is even a requirement for older versions of RAC, such as prior to 11g. The XA failover is also supported by the Multi Data Source and transaction manager implementations. If a pinned RAC instance suffers a failure, then a global transaction can complete utilizing a different RAC instance using a connection obtained one of the other member data sources.

Reference: Oracle WebLogic Server Active GridLink for Oracle Real Application Clusters(RAC)

Correct Answer: B

To manage work in your applications, you define one or more of the following Work Manager components:

Fair Share Request Class:

Response Time Request Class:

Min Threads Constraint:

Max Threads Constraint:

Capacity Constraint

Context Request Class:

Note:

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max-threads-constraint--This constraint limits the number of concurrent threads executing requests from the constrained work set. The default is unlimited. For example, consider a constraint defined with maximum threads of 10 and shared by 3 entry points. The scheduling logic ensures that not more than 10 threads are executing requests from the three entry points combined. A max-threads-constraint can be defined in terms of a the availability of resource that requests depend upon, such as a connection pool. A max-threads-constraint might, but does not necessarily, prevent a request class from taking its fair share of threads or meeting its response time goal. Once the constraint is reached the server does not schedule requests of this type until the number of concurrent executions falls below the limit. The server then schedules work based on the fair share or response time goal.

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WebLogic Server prioritizes work and allocates threads based on an execution model that takes into account administrator-defined parameters and actual run-time performance and throughput.

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WebLogic Server uses a single thread pool, in which all types of work are executed. WebLogic Server

Administrators can configure a set of scheduling guidelines and associate them with one or more applications, or with particular application components.

prioritizes work based on rules you define, and run-time metrics, including the actual time it takes to execute a request and the rate at which requests are entering and leaving the pool.

The common thread pool changes its size automatically to maximize throughput. The queue monitors throughput over time and based on history, determines whether to adjust the thread count. For example, if historical throughput statistics indicate that a higher thread count increased throughput, WebLogic increases the thread count. Similarly, if statistics indicate that fewer threads did not reduce throughput, WebLogic decreases the thread count. This new strategy makes it easier for administrators to allocate processing resources and manage performance, avoiding the effort and complexity involved in configuring, monitoring, and tuning custom executes queues.

Reference: Using Work Managers to Optimize Scheduled Work

Correct Answer: BD

By default, JMS messages never expire. When applications send messages to queues or topics with durable subscribers, WebLogic must retain the message until it is consumed. This is fine in most point-topoint messaging applications because consumers are constantly consuming messages. Any message sent to a queue will typically be consumed in a relatively short period of time. If the consumers get disconnected, they will usually reconnect as soon as possible and start processing any messages that might have built up in the queue.

D: For durable subscribers to a topic, this is not necessarily true. The messaging system is forced to retain any message that has not been consumed by a durable subscriber, regardless of whether that durable subscriber will ever return. In this case, WebLogic is at the mercy of the durable subscriber to unsubscribe when it no longer wishes to receive the messages. If the durable subscriber logic is flawed in such a way that the subscribers do not unsubscribe properly, the messaging system will start to fill up with messages that may never be delivered. This calls for real caution in using durable subscribers. Fortunately, there is another way to help deal with this problem. Message expiration can be set at the connection factory level. Using a connection factory's default time-to-live attribute, we can specify the number of milliseconds that WebLogic should retain an undelivered message after it is sent.

Correct Answer: C

The Clone WebLogic Domain option launches a wizard that enables you to clone a WebLogic Domain from an existing reference domain that is already discovered with Cloud Control. It allows you to clone the Middleware Home and its binaries, and the domain configuration.

* If you selected the Cloning a WebLogic Domain option, the Middleware Provisioning: Domain Configuration page appears. This page contains a set of links to several pages where you can enter the properties that are most likely to be reconfigured like domain name, listen addresses for the administration server and managed servers, Node Manager/Machine configuration, and JDBC data sources.

Correct Answer: ABE

A: Print more details at garbage collection.

B: Print timestamps at garbage collection.

C: The youngest generation collection does not require a guarantee of full promotion of all live objects.

E: Default values are listed for Java SE 6 for Solaris Sparc with -server.

Reference: Java HotSpot VM Options

Correct Answer: D

WAN HTTP Session State Replication

Resources in a wide area network (WAN) are frequently spread across separate geographical regions. In

addition to requiring network traffic to cross long distances, these resources are often separated by

multiple routers and other network bottle necks. Network communication in a WAN generally has higher

latency and slower interconnect. Slower network performance within a WAN makes it difficult to use a

synchronous replication mechanism like the one used within a MAN. WebLogic Server provides failover

across clusters in WAN by using an asynchronous data replication scheme.

Note:

HTTP Session State Replication

Weblogic Server uses two methods for replicating HTTP session state across clusters:

in-memory replication

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Using in-memory replication, WebLogic Server copies a session state from one server instance to another. The primary server creates a primary session state on the server to which the client first connects, and a secondary replica on another WebLogic Server instance in the cluster. The replica is kept up-to-date so that it may be used if the server that hosts the servlet fails.

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JDBC-based persistence In JDBC-based persistence, WebLogic Server maintains the HTTP session state of a servlet or JSP using file-based or JDBC-based persistence. JDBC-based persistence is also used for HTTP session state replication within a Wide Area Network (WAN).

Correct Answer: CEF

Note:

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Two or more Managed Servers can be configured as a WebLogic Server cluster to increase application scalability and availability. In a WebLogic Server cluster, most resources and services are deployed identically to each Managed Server (as opposed to a single Managed Server), enabling failover and load balancing. A single domain can contain multiple WebLogic Server clusters, as well as multiple Managed

Servers that are not configured as clusters. The key difference between clustered and non-clustered Managed Servers is support for failover and load balancing. These features are available only in a cluster of Managed Servers.

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A WebLogic Server cluster provides these benefits: Scalability The capacity of an application deployed on a WebLogic Server cluster can be increased dynamically to meet demand. You can add server instances to a cluster without interruption of service--the application continues to run without impact to clients and end users. High-Availability In a WebLogic Server cluster, application processing can continue when a server instance fails. You "cluster" application components by deploying them on multiple server instances in the cluster--so, if a server instance on which a component is running fails, another server instance on which that component is deployed can continue application processing.

Correct Answer: B

A Node Manager process is not associated with a specific WebLogic domain but with a machine. You can use the same Node Manager process to control server instances in any WebLogic Server domain, as long as the server instances reside on the same machine as the Node Manager process. Node Manager must run on each computer that hosts WebLogic Server instances--whether Administration Server or Managed Server--that you want to control with Node Manager. Reference: Overview of WebLogic Server Domains

Correct Answer: AC

Note:

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Apache Maven is a software tool for building and managing Java-based projects. WebLogic Server provides support for Maven through the provisioning of plug-ins that enable you to perform various operations on WebLogic Server from within a Maven environment.

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Continuous Integration is a software engineering practice which attempts to improve quality and reduce time to deliver software by applying small, frequent quality control efforts. It is characterized by these key practices: Use of a version control system All developers commit to the `HEAD' (main code line) every day The product is built on every commit The build must be automated and fast Automated deployment to a production-like environment Automated testing Results of all builds are published (so everyone can see who broke the build) Deliverables are easily available (for developers, testers, other stakeholders)

Correct Answer: ABCE

Note:

* Example If you have additional Coherence caches running on Coherence*Web, then you must merge the cache configuration information (typically defined in the coherence-cache-config.xml file) with the session configuration contained in the session-cache-config.xml file. The cache and session configuration must be consistent across WebLogic Server and Coherence cache servers.