IMS Connectivity in an On Demand Environment: A Practical Guide to IMS Connectivity

Chapter 2. Open Transaction Manager Access 21

 OTMAASY=Y/N

OTMAASY=Y (yes) specifies that a nonresponse transaction originating from a

program-to-program switch be scheduled asynchronously. This parameter is for

send-then-commit (commit mode 1) messages only. A DFS2082 message is not issued for

a transaction scheduled asynchronously.

OTMAASY=Y can also be used in multiple program-to-program switches to ensure that

only the response transaction is scheduled synchronously.

Setting this parameter to Y can help to prevent a race condition that can occur when you

do multiple program switches in a send-then-commit transaction and you mix response

and nonresponse transactions. OTMAASY ensures that the response transaction, the one

most likely to return IOPCB output, is scheduled synchronously.

The default value is OTMAASY= N. See 2.3.3, “IMS commit mode 1 message processing”

on page 16 for a more detailed discussion of the OTMAASY parameter.

Checking the status of OTMA

Use the /DISPLAY OTMA command to check the status of OTMA in IMS. Example 2-1 shows

that SCSIM9G is the XCF member name (OTMANM) of the OTMA server (that is IMS), it is

active (OTMA=Y), and it belongs to the XCF group IMS9EXCF (GRNAME). The OTMASE

parameter is set or defaulted to FULL. HWS910G in this example is an XCF member name of

an OTMA client that happens to be IMS Connect in this case.

Example 2-1 /DIS OTMA command output

DFS000I GROUP/MEMBER XCF-STATUS USER-STATUS SECURITY IMSG

DFS000I IMS9EXCF IMSG

DFS000I -SCSIM9G ACTIVE SERVER FULL IMSG

DFS000I -HWS910G ACTIVE ACCEPT TRAFFIC IMSG

DFS000I *05178/195343* IMSG

2.5 OTMA security issues

Use the /SECURE command to control the RACF security level for input from OTMA clients.

It is used for administrative control of the IMS environment and as an emergency operations

control command to throttle RACF activity, without requiring an IMS shutdown. The /SEC

OTMA command is used with the CHECK, FULL, NONE, or PROFILE parameters.

You can use the /DISPLAY OTMA command to show the security level that is currently in

effect. Use the OTMASE execution parameter to change the level of security desired at the

IMS startup. The default is FULL. The /SECURE OTMA command overrides the value you

specify in the OTMASE keyword. If you do not specify the OTMASE keyword, IMS retains the

OTMA security settings (which are established by the /SECURE OTMA command) after a

warm start or emergency restart.

The parameters in the /SEC OTMA command have the following meanings:

 CHECK

Causes existing RACF calls to be made. IMS commands are checked using the RACF

resource class of CIMS. IMS transactions are checked using TIMS.

 FULL

Causes the same processing as the CHECK parameter, but uses additional RACF calls to

create the security environment for dependent regions.