The OSDI DEFINE SERVICE command is described completely in Appendix A,
"OSDI Subsystem Command Reference". Here, we cover DEFINE parameter considerations that are specific to an Oracle database service.
Service Name
The service name for a database can be anything that you want within the content limitations described in Appendix A. By default, OSDI will use the service name as the SID for the service. (The SID is an identifier that end users or application developers must supply to connect an application to a particular database.) The SID can be specified separately, however, and is not required to be the same as the service name.
Database Service Definition
Although OSDI permits service names up to eight characters long, the name you use for a database service should be seven characters or less due to a length limitation on what is stored in the database control file. The OSDI service name appears in the Oracle data dictionary view V$INSTANCE in column
INSTANCE_NAME.
TYPE
The TYPE parameter for a database service must be specified as ORA.
PROC
This parameter specifies the name of a service JCL procedure that you will place in one of your system procedure libraries. The procedure need not exist when DEFINE SERVICE is issued, but it must be in place before the service is started.
The procedure name can be anything that you choose or that the naming standards of your installation require. The requirements for this procedure are discussed in section "Database Region JCL" on page 3-5.
PARM
The PARM for a database service specifies the name of a z/OS data set containing service initialization parameters. These are z/OS-specific parameters (not the Oracle RDBMS init.ora file startup parameters) and are described in the section
"Database Region Parameters" on page 3-9. Typically, PARM will specify a member Note: If you specify a service name that is the same as any
existing subsystem name in your system (Oracle database or otherwise), then you must also specify a JOBNAME parameter that is not the same as any existing subsystem. If you do not use unique names, then OSDI starts the service using the service name as the job identifier. When z/OS processes a start for an address space whose job name or job identifier matches a known subsystem, the job runs under control of the master subsystem instead of under control of JES.
Caution: Running OSDI services under the master subsystem is not supported. This situation must be avoided by making sure that the service runs with a job name or a job identifier that is not the same as any subsystem name.
Database Service Definition
of a PDS (Partitioned Data Set) that is used for various Oracle parameter files. If no member name is included in the PARM string, then the specified data set must be sequential (DSORG=PS).
MAXAS
If you want to exploit the multiple-address-space server features of OSDI, then you should specify the MAXAS parameter on DEFINE SERVICE with a value greater than the default of 1. This sets the maximum number of address spaces for the service, which may be greater than the number started when the service is first brought up. (The number of address spaces to start initially is a database region parameter.) This parameter can be altered with OSDI commands as long as the database service is not active.
JOBNAME
When you run a database service with multiple address spaces, the JOBNAME parameter of DEFINE SERVICE can be used to cause each address space to have a distinct jobname. Although this is not required, it may be desirable if you use z/OS facilities (such as RMF) that distinguish address spaces by jobname. To do this, specify JOBNAME(name), where name is a one-character to five-character jobname prefix followed by an asterisk, as shown. As each address space is started,
OSDI
substitutes a three-digit address space counter for the asterisk (001, 002, and so on) to produce the final jobname. You can also use JOBNAME to cause the service to run with a jobname different from the service name (which is used by default).
As discussed in the Note in the preceding page, you must specify a JOBNAME parameter if the service name matches any existing subsystem name in your z/OS system.
SID
The SID parameter specifies a unique identifier for the service. It is a critical element in the process that is used by Oracle database applications to specify the instance to which they need to connect. (Inbound network clients specify a SID in the Oracle database network address string that must match the SID that is specified in DEFINE SERVICE. Local z/OS clients connecting via cross-memory specify the SID in any of several ways.) Although the SID can be up to eight characters long, you may want to specify a SID that is four characters or less in order to enable a z/OS-specific feature that local z/OS clients can use to specify a target database. This feature relies on a dummy JCL DD statement (or TSO allocation) whose DD name begins with "ORA@" and ends with a one-character to four-character SID of the target database instance. If you choose a SID longer than