Question 1: When should JMS be used over web services in Siebel integration requirement?Answer: JMS queues are based on store and forward guaranteed delivery mechanism. That means source system sends the message to middleware which holds the message in queue until Siebel server reads it thus message is never lost.
However on other side web services doesn't have retry mechanism in architecture. In case of heavy load or server unavailability message can be lost if source system can't resend it. Benefit of using web services is that they are faster to develop, setup and maintain.
Question 2: How does JMS integration works in Siebel?Answer : Siebel has JMS receiver server component which can pull XML messages from JMS queue for data transfer. For JMS components to get messages from JMS server Siebel needs to have JAVA installed on Siebel server.
Question 3 : What is the difference between queue and a topic of JMS?Answer: Queue is is implementation of first in first out data structure, and can be used only between one source and one consumer. Once XML message is consumed by consumer it is deleted from the queue.
Topics also have queue like store and forward mechanism but with the difference that they do not delete XML messages immediately after it has been read, the same message can be read by another consumer (application). Thus well suited for 1 to many integration scenario.
Questions 4 : What steps are involved in JMS component setup in Siebel?Answer: Siebel JMS setup involves minimum three items :
- Setup of JVM (Java) subsystem
This tells where is Java files and server details of JMS server.
- Setup of JMS subsystem
This contains queue or topic information
- Setup of receiver component
This component pulls XML messages from JMS server mentioned in JVM sub system from queue mentioned in JMS subsystem.
Question 5: What is jndi.properties file? What it is necessary?Answer: Java subsystem required for JMS integration required JMS server location information such IP address and port. This information is kept in jndi.properties file in Siebel filesystem.
It looks something like this: https://docs.oracle.com/javase/jndi/tutorial/beyond/env/src/jndi.properties
Questions 6: what kind of logging is available for JMS transport?Answer: EAI JMS Transport provides two logging methods, first one is the traditional Siebel logs which can be turned on by increasing log level of receiver component.
Second type of logs are Java logs which generated by Java virtual machine installed on Siebel server , they can get turned on by setting VMOptions in Java subsystem.
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