Chapter 3 Destinations : Creating and Modifying Destinations

Creating and Modifying Destinations
Destinations are typically "static" administered objects that can be stored in a JNDI or LDAP server. Administered objects can also be stored in the EMS server and looked up using the EMS implementation of JNDI. This section describes how to use the EMS Administration Tool described in Chapter 6 to create and modify destination objects in EMS.
You create a queue using the create queue command and a topic using the create topic command. For example, to create a new queue named myQueue, enter:
   create queue myQueue
To create a topic named myTopic, enter:
   create topic myTopic
The queue and topic data stored on the EMS server is located in the queues.conf and topics.conf files, respectively. You can use the show queues and show topics commands to list all of the queues and topics on your EMS server and the show queue and show topic commands to show the configuration details of specific queues and topics.
A queue or topic may include optional properties that define the specific characteristics of the destination. These properties are described in Destination Properties and they can be specified when creating the queue or topic or modified for an existing queue or topic using the addprop queue, addprop topic, setprop queue, setprop topic, removeprop queue, and removeprop topic commands.
For example, to discard messages on myQueue when the number of queued messages exceeds 1000, you can set an overflowPolicy by entering:
addprop queue myQueue maxmsgs=1000,overflowPolicy=discardOld
To change the overflowPolicy from discardOld to rejectIncoming, enter:
addprop queue myQueue overflowPolicy=rejectIncoming
The setprop queue and setprop topic commands remove properties that are not explicitly set by the command. For example, to change maxmsgs to 100 and to remove the overflowPolicy parameter, enter:
setprop queue myQueue maxmsgs=100
Creating Secure Destinations
By default, all authenticated EMS users have permissions to perform any action on any topic or queue. You can set the secure property on a topic or queue and then use the grant topic or grant queue command to specify which users and/or groups are allowed to perform which actions on the destination.
The secure property requires that you enable the authorization property on the EMS server.
For example, to create a secure queue, named myQueue, to which only users "joe" and "eric" can send messages and "sally" can receive messages, in the EMS Administration Tool, enter:
   set server authorization=enabled
   create queue myQueue secure
   grant queue myQueue joe send
   grant queue myQueue eric send
   grant queue myQueue sally receive
See Chapter 8, Authentication and Permissions for more information.