Indicating the IXGLOGR address space is not to start on a system

The LOGR subsystem specification generally allows you to read log stream data without having to rewrite your existing applications. See Activate the LOGR subsystem for more this topic.

However, there are sysplex configurations where it would be appropriate to not allow the IXGLOGR address space to start on a system. For example, in certain Geographically Dispersed Parallel Sysplex® (GDPS®) configurations, the controlling, or k–, system may need to have System Logger not active to avoid any log stream activity from occurring on that system.

If you need to have the IXGLOGR address space not be started on a system, specify the following:

In an IEFSSNxx parmlib member and use the member during the system IPL:
```
SUBSYS SUBNAME(LOGR) INITRTN(IXGSSINT) INITPARM(IXGLOGR=NOSTART)
```
Since IEFSSNxx parmlib members cannot contain the new and old format definitions in the same IEFSSNxx parmlib member, you might need to define a new parmlib member for the LOGR subsystem specification and concatenate it with other IEFSSNxx parmlib members.
In a COMMNDxx parameter member used during the IPL:
```
COM='SETSSI ADD,SUBNAME=LOGR,INITRTN=IXGSSINT,INITPARM=''IXGLOGR=NOSTART'''
```
If a SETSSI command is issued after the first initialization of the IXGLOGR address space then the INITPARM option is ignored and will have no effect on the IXGLOGR address space.

Note: The above format for specifying the LOGR subsystem options is required, but the installation can choose any valid subsystem name using the SUBNAME keyword (it does not have to be LOGR). Make certain, however, that the subsystem name specified in the SUBNAME parameter matches the corresponding name in the SUBSYS option in any JCL or dynamic allocation intended to use the system logger subsystem functions.

The IXGLOGR=NOSTART specification in the INITPARM keyword will result in the following system action:

The LOGR or named subsystem (ssname) functional routines will be established.
However, any JCL DD SUBSYS=(LOGR,exit,...) or dynamic allocation equivalents will likely result in the subsystem exit routine encountering a return code 8, reason code X'0814' condition (see IxgRsnCodeNotAvailForIPL in IXGCON macro).

For example, if the logger subsystem default exit IXGSEXIT was requested in this environment, then Logger message IXG511I would be issued indicating the IXGCONN service failed with the return and reason codes listed above.

Errors returned by any Logger subsystem exit routine will cause Logger to issue message IXG504I indicating the exit error condition.
The IXGLOGR address space will not complete its initialization at the end of Master Scheduler Initialization (MSI), and the address space will terminate.
Attempts to start the IXGLOGR address space (re: IXGLOGRS procedure) will not complete successfully as Logger will not allow the IXGLOGR address space to start because of the IXGLOGR=NOSTART specification.
Message IXG053I is issued indicating the IXGLOGR address space is not available until another IPL is done for this system.
Any System Logger API (IXGxxxxx) service request made on this system will result in the requestor receiving a return code 8, reason code X'0814'(IxgRsnCodeNotAvailForIPL) condition.