Using the IXLCONN macro for rebuilds

The first connector to issue IXLCONN with REBUILD or REQTYPE=REBUILDCONNECT allocates the new structure. The first connected user also defines the attributes for the new structure. When the new structure is allocated, pending policy changes to structure size or location also apply. Other users issue IXLCONN REBUILD to connect to the new structure but cannot change the structure attributes. The connect answer area contains information about the rules used to allocate the structure. It is the connector's responsibility to verify that the attributes of the structure are acceptable.

To issue IXLCONN REBUILD or use the default the user must be connected to the original structure. The user must issue IXLCONN REBUILD with the same structure name and CONNAME as the original structure. Table 1 lists the structure attributes that users can change when rebuilding a structure.

Table 1. Structure attributes that can be changed with rebuild connect
Cache	List	Lock
STRSIZE	STRSIZE	STRSIZE
NONVOLREQ	NONVOLREQ	NONVOLREQ
ACCESSTIME	ACCESSTIME	ACCESSTIME
ELEMCHAR*	ELEMCHAR*	LOCKENTRIES
ELEMINCRNUM	ELEMINCRNUM	MONITORSTORAGE
MAXELEMNUM*	MAXELEMNUM*	NUMUSERS
DIRRATIO*	ENTRYRATIO*	MAXCONN
ELEMENTRATIO*	ELEMENTRATIO*
ADJUNCT	ADJUNCTP*
VECTORLEN	VECTORLEN
NUMCOCLASS	LISTCNTLTYPE*
NUMSTGCLASS	REFOPTION*
UDFORDER	LISTHEADERS
NAMECLASSMASK	EMCSTGPCT*
	MAXCONN

Note: An asterisk indicates that the parameter is ignored by a system with APAR OA33448 installed when KEEPRATIOS=YES is specified on IXLCONN REBLD.

The following restrictions also apply:

IXLCONN REBUILD must be issued from the same system and address space as the original IXLCONN request. You can issue IXLCONN REBUILD from a task other than the task that issued the original IXLCONN request or from the same task that issued the original IXLCONN request.
Users of IXLCONN REBUILD cannot change the following attributes of the structure:
- TYPE (structure type)
- RECORD (record data for lock structure)
- RNAMELEN (resource name length for lock structure)
If users specified VECTORLEN on the IXLCONN request for the original structure, then they must also specify it on the IXLCONN REBUILD request for the rebuild structure. A user can, however, change the size of VECTORLEN on the IXLCONN REBUILD request. If users did not specify VECTORLEN on the IXLCONN request for the original structure, then they must not specify it on the IXLCONN REBUILD request.
If users specified LOCKENTRIES on the IXLCONN request for the original structure, then they must also specify it on the IXLCONN REBUILD request for the rebuild structure. A user can, however, change the value for the number of lockentries on the IXLCONN REBUILD request.
The value for NUMUSERS (specified for lock structures on IXLCONN to define the maximum number of connected users) or MAXCONN (specified for list or lock structures on IXLCONN) cannot be less than the value specified for the original structure.
When changing the size (STRSIZE) of a structure, the maximum structure size is determined by the SIZE parameter in the CFRM active policy. The system rejects a request specifying a STRSIZE larger than the current maximum structure size in the CFRM active policy.
Note: If the size of the structure has been altered to a value different from the SIZE parameter in the CFRM active policy, it is the responsibility of the installation to change that value, if appropriate.
When allocating a percentage of available structure storage for event monitor controls, it IS possible on IXLCONN REBUILD requests for the connector to specify a percentage value (EMCSTGPCT) that is different from what was specified on the initial IXLCONN request. Thus, a user could specify that the rebuilt structure was to provide for EMCs even if the original structure did not. However, note that it is NOT possible to request the allocation of a local vector on an IXLCONN REBUILD request unless the initial IXLCONN request had requested a local vector.
Note also that a user cannot change the specification of a list transition exit name when invoking IXLCONN REBUILD. LISTTRANEXIT is relevant to both sublist monitoring and event queue monitoring.
The following keywords are IGNORED for rebuild connect requests (IXLCONN REBUILD or IXLCONN REQTYPE=REBUILDCONNECT):
- CFLEVEL
- CONTEXIT
- NOTIFYEXIT
- LISTTRANEXIT.
Note that some of these keywords are required, and you must therefore specify them for rebuild connect requests.
The following keywords have no meaning when specified on IXLCONN REBUILD requests because the attributes are propagated from the original IXLCONN request. However, you might need to specify them on the IXLCONN REBUILD request or the request fails.
- STRDISP (structure disposition)
- CONDISP (connection disposition)
- CONDATA (connect data)
- EVENTEXIT (event exit name)
- COMPLETEEXIT (complete exit name)
- CONLEVEL (connection level)
- ALLOWREBLD (whether rebuild is allowed)
- ALLOWDUPREBLD (whether duplexing rebuild is allowed)
- ALLOWAUTO (whether system-managed processes are supported).
The value for NUMUSERS (specified for lock structures on IXLCONN to define the maximum number of connected users) or MAXCONN (specified for list or lock structures on IXLCONN to define the maximum number of connected users) cannot be less than the number of currently in-use connections to the old structure instance.

The location of the new structure depends on the following:

If LOCATION=OTHER was specified when the rebuild was initiated, XES will not allocate the structure in the same coupling facility as the original structure. (LOCATION=OTHER is assumed for duplexing rebuild.)
For structure rebuild, XES allocates the structure in the first coupling facility in the preference list that meets the standard allocation requirements. See Allocating a Structure in a Coupling Facility.
For duplexing rebuild, XES attempts to allocate the structure in a coupling facility in the preference list that not only meets the standard allocation requirements but also provides failure-independence with respect to the coupling facility in which the old structure is allocated. If such a coupling facility is not available, the installation should consider changing the active CFRM policy so that the structure can be duplexed in a failure-independent environment. See Planning for Coupling Facility Failure-Independence for a description of the failure-independent coupling facility attribute.