MSC - Multiple Systems Coupling service aids

Various types of traces are available to help you diagnose Multiple Systems Coupling (MSC) problem in a non-Database Control (DBCTL) environment.

Multiple Systems Coupling communication task trace
The flow through an MSC communication task is similar to that through the terminal communication task. The register 0 trace is read in the same manner, and most of the MSC analyzer and MSC DDM entry points provide the same functions as the terminal communications analyzer and DDMs.
Multiple Systems Coupling device-dependent module
A Multiple Systems Coupling (MSC) device-dependent module performs all of the functions unique to a type of link.
Multiple Systems Coupling traces
Multiple Systems Coupling traces include MSC Message Processing trace, Main storage-to-main storage access method trace, and Main storage-to-main storage save set trace.
Diagnosing link problems
Turn traces on for the appropriate lines from either the IMS master terminal or, if you are using type-2 commands, from the Operations Manager (OM) API. Trace all terminals on a line.
MSS1 and MSS2 records
MSS1 and MSS2 records are created as a result of ABORT processing when an I/O error (correctable or not) occurs. All available control blocks are snapped, regardless of any trace options in effect on the link involved.
MSS3 and MSS4 records
The MSS3 and MSS4 records capture link control blocks when links are started and stopped. MSS3 captures information when links are stopped. MSS4 captures information when the links are started.
Channel-to-channel access method trace stack (LXB trace)
The LXB trace stack is designed to be used in conjunction with the module listings to provide a detailed trace of instruction flow through the channel-to-channel (CTC) access method.

Parent topic: Diagnosis