This document describes facilities that are not supported for cluster nuclei running under Adabas Parallel Services or for which restricted support is provided.
The following facilities are supported normally for noncluster nuclei; however, for an Adabas cluster nucleus running in an Adabas Parallel Services environment, the following features are not available and cannot be specified:
MODE=SINGLE
sequential protection log (DDSIBA)
synchronous buffer flush (LFIOP=0)
The following features are not currently supported for an Adabas cluster nucleus running in an Adabas Parallel Services version 7.4 environment, but will be supported in subsequent versions of the product:
READONLY=YES (receives PARM ERROR 71 if attempted)
UTIONLY=YES can be specified for a cluster nucleus; if you start cluster nuclei with conflicting settings of UTIONLY, the system will change them to conform to the setting of the first active nucleus. Currently, however, the UTIONLY setting cannot be changed using an ADADBS OPERCOM or Adabas Online System function. Once the cluster is started, the only way to change the UTIONLY setting is to bring down the whole cluster and restart it with a different setting.
advance file lock (ALOCKF)
two-phase commit processing (DTP=RM), but limited support (DTP=ET) for distributed transactions is available. Read Limited Distributed Transaction Support, for more information.
online reorder
Enhanced error recovery is supported; however, option changes are effective only for the local nucleus. TCP/IP direct links are supported; however, the IP address/port is tied to an individual nucleus.
The triggers and stored procedures facility (SPT) is fully supported in a cluster environment:
The ADARUN SPT parameter is global and must be set the same on all active nuclei.
When a REFRESH is executed, the trigger table is passed to all active nuclei.
Only the first nucleus to initialize reads the trigger file to create the trigger table; all subsequent nuclei obtain the trigger table from one of the already active nuclei.
Adabas Parallel Services can in a limited way participate in distributed Adabas transactions coordinated by the Adabas Transaction Manager, as follows:
In each distributed transaction, a single cluster database is allowed to participate. Different cluster databases can participate in different distributed transactions.
All nuclei of a cluster database participating in distributed transactions must be run with the new ADARUN parameter setting DTP=ET.
Cluster databases can participate in distributed transactions only if all resource managers involved in these transactions are Adabas databases running with DTP=RM. DTP=ET cannot be supported when an external transaction framework is included in the transaction (CICS/RMI or RRMS).
Full support by cluster databases for distributed transactions will be provided in a subsequent release of Adabas Parallel Services.
The operator command and AOS function CLUFREEUSER is available for situations where leftover User Table Elements in common storage need to be cleaned up. This function deletes such User Table Elements according to specified criteria.
By default, the cluster nucleus receiving this function deletes all User Table Elements assigned to itself which it does not know of (i.e., for which it has no User Queue Elements). If the GLOBAL option is specified, all User Table Elements are deleted that are assigned to nuclei that are no longer active, or that have no associated User Queue Elements in their assigned nuclei. For more information about the User Table Cleanup, see Maintain the User Table.
