CA Datacom/AD Environment › CA Datacom/DB Components and System Areas › Directory (CXX)

Directory (CXX)

The CXX (or Control Directory) functions as a system catalog. The significant pieces of the data definitions stored in the CA Datacom Datadictionary are used to create the CXX. The CXX contains all of the information that is needed to satisfy any non-SQL request to CA Datacom/DB. The CA Datacom Dictionary facility is comprised of the following databases:

• Data Dictionary (DD or DBID 0002) - Stores the basic structure definitions and attributes of the majority of the Datacom entities needed for RAAT or SAAT.
• Data Definition Dictionary (DDD or DBID 00015) - Used for SQL processing, information concerning tables, views, and synonyms is obtained from both the CXX and the CA Datacom Datadictionary. The CA Datacom Datadictionary portion of the information is obtained from a high performance cache called the Data Definition Directory (DDD). This enhances SQL performance.

CA distributes the CXX with all required definitions for the base CA Datacom/AD system and recommended sample databases. Each CA using product that installs CA Datacom/AD adds its own database definitions to the CXX.

The name for the CXX that you assign at your site is critical and needs to be unique for each CXX data set. If you have the need for multiple MUF environments, each is normally going to have a unique CXX name and a unique set of data sets that it is going to own.

Because a site has many z/OS Systems and multiple Sysplex occurrences, there could be a need for more than one CA Datacom environment.

To separate the identity of each environment, a unique name must be assigned. The name should be seven (7) or less positions long and meet the requirements needed to be part of a data set name node. To make data set ownership clear and prevent problems caused by having data sets used by multiple (or wrong) environments, it is a best practice (though not a requirement) to make the name a node in each data set.

The CA Datacom system data set controlling the environment is the Directory with a data set DDNAME of CXX. The name selected for each environment is provided to CA Datacom as the CXXNAME. Access to the data set environment is primarily through the MUF and secondarily through the utility function processor named DBUTLTY. The MUF is often a single instance of an executing program DBMUFPR to provide services to all accesses to the data in this environment. In this configuration, the name of the MUF would be the same as the name of the CXX. The MUF can also be configured as two instances or Jobs with one the primary and active server and the second doing some tracking as a shadow to take over processing quickly should the primary fail. In this configuration, the CXX name would become the MUFPLEX name as the identity of the group of MUF instances, and each MUF instance would need its own identity or MUF name that would be the CXX name suffix with numbers 1 and 2 or the letters A and B.

To define the specific environment, CA Datacom provides one Macro (DBSYSID) with key word options providing the names of the CXX and the MUF instances. In addition, it provides many other options that define the environment configuration.

Important! The CXX, CA Datacom Datadictionary, and the DDD-Database are the heart of the CA Datacom/AD production system. Protect the heart of the system by retaining the backups taken at the end of each install or upgrade. Always back up the CXX and the two CA Datacom Datadictionary databases (DBIDs 2 and 15) at the same time.