Simplifying OMEGAMON XE for CICS on z/OS startup using the RETRY option.
RichardBurford 120000E258 Visits (1852)
OMEGAMON XE for CICS on z/OS code running in a CICS address space will establish a connection to the common interface started task (KOCCI). In order for this process to work correctly the KOCCI STC must be initialized before OMEGAMON is started in CICS.
The enhancement described here introduces the option to allow the CICS address space to finish initialization and connect to the KOCCI STC whenever it becomes available.
An early approach was the addition of the OCCIREQ DD card in the CICS JCL, which makes the OMEGAMON code in the CICS address space wait until the KOCCI STC is initialized. The main disadvantage of this technique is that CICS regions will wait in OMEGAMON code, with the result that the startup of CICS regions can be delayed until the KOCCI STC is available.
A better approach, developed in response to customer requests and introduced in v420, is the use of the RETRY parameter.
The RETRY parameter, specified in the CICS INITPARM data, allows you to specify an interval and a retry count. When OMEGAMON is initialized in the CICS address space it attempts to establish a connection to the KOCCI STC. If the KOCCI STC is not available at that point and the RETRY parameter is specified, the OMEGAMON code will wait for the specified interval and, optionally, the specified number of times, to retry the connection. This new processing does not delay CICS initialization regardless of whether the code is executed during PLT processing or as a result of operator input from a CICS terminal session.
An example of the parameter is shown here.
In this example the RETRY parameter specifies that the connection will be retried every 30 seconds, for a maximum of 20 attempts.
The parameter is defined as RETRY(tt,cc) where tt is an interval in seconds, and cc is the maximum attempts that will be made. The parameter can be specified as RETRY(tt) in which case the attempts will be made indefinitely or until you cancel the process.
You will see messages issued if you specify the RETRY parameter. The messages indicate the progress of the RETRY processing, and are sent to the MVS console. If the OMEG INIT command is entered from a CICS terminal the messages will also display there.
KCP1040I OCOMEG OMEGAMON II FOR CICS WILL RETRY: INTERVAL 000030 COUNT 000020
If the RETRY count is reached a message is also issued.
KCP1042I OCOMEG OMEGAMON II FOR CICS RETRY LIMIT REACHED
Additionally the CANCEL option of the OMEG command allows you to cancel the RETRY process. Entering OMEG CANCEL results in the following message.
KCP1047E OCOMEG OMEGAMON II FOR CICS RETRY PROCESSING HAS TERMINATED
Messages are also issued if the INITPARM data is incorrectly specified.
For customers who do not want their CICS regions to wait for the KOCCI STC to initialize the RETRY option may offer a solution.