-START DB2 (DB2)
The DB2® command START DB2 initializes the DB2 subsystem. When the operation is complete, the DB2 subsystem is active and available to TSO applications and to other subsystems (for example, IMS™ and CICS®).
The effect of restarting the system can be controlled by a conditional restart control record, which you create by using the DSNJU003 (change log inventory) utility. For more details about the effects, see Usage notes.
Abbreviation: -STA DB2
Environment
This command can be issued only from a z/OS® console. The name of the DB2 subsystem is determined by the command prefix. For example, -START indicates that the DB2 subsystem to be started is the one with '-' as the command prefix.
The command is rejected if the DB2 subsystem is already active. The restart recovery status of DB2 resources is determined from the prior DB2 shutdown status.
Data sharing scope: Member
Authorization
None is required. However, the command can be executed only from a z/OS console with the START command capability.
Syntax
>>-START DB2--+-------------------------+-----------------------> '-PARM(---module name---)-' >--+-----------------------+--+---------------------+-----------> | .-DSNCDECP--. | | .-*-----. | '-DECP(-+-----------+-)-' '-ACCESS(-+-------+-)-' '-decp-name-' '-MAINT-' >--+-------------------------+--+------------------------+------> | .-NO---------. | '-MSTR(jcl-substitution)-' '-LIGHT(-+------------+-)-' +-YES--------+ '-NOINDOUBTS-' >--+------------------------+--+------------------------+------>< '-DBM1(jcl-substitution)-' '-DIST(jcl-substitution)-'
Option descriptions
- PARM ( module-name )
-
Specifies the load module that contains the DB2 subsystem parameters.
The default is the name of the parameter module that was specified on panel DSNTIPO when the installation CLIST was run. The default can also be changed if you update ZPARM(default-module-name) in the ssnmMSTR DB2 subsystem startup procedure.
- DECP
- Specifies the name of the load module that
contains DB2 application parameter
defaults.
decp-name is the name of a module that is provided by the installation. The default name is DSNHDECP. If the specified module is not found or cannot be loaded, an error is issued, and the DB2 subsystem does not start.
- ACCESS
- Specifies whether access to DB2
is to be general or restricted. Abbreviation: ACC
- (*)
- Makes access general; all authorized users can connect to DB2.
The default is ACCESS( * ).
- (MAINT)
- Prohibits access to any authorization IDs other than installation SYSADM, installation
SYSOPR, and SECADM.
For data sharing, ACCESS(MAINT) restricts access on only the DB2 member on which you execute this command. Other members of the data sharing group are unaffected.
- LIGHT
- Specifies
whether a light restart is to be performed in a data sharing environment.
- (NO)
- A light restart is not performed.
- (YES)
- Specifies that a light restart is to be performed. DB2 starts with reduced storage, waits for resolution of indoubt units of recovery, and terminates normally after freeing retained locks.
- (NOINDOUBTS)
- Specifies that DB2, during a light restart, does not wait for indoubt units of recovery to resolve before it terminates.
- MSTR ( jcl-substitution )
- Gives parameters and values to be substituted in the EXEC statement of the JCL that executes the startup procedure for the system services address space.
- DBM1 ( jcl-substitution )
- Gives parameters and values to be substituted in the EXEC statement of the JCL that executes the startup procedure for the database services address space.
- DIST ( jcl-substitution )
- Gives
parameters and values to be substituted in the EXEC statement of the
JCL that executes the startup procedure for the distributed services
address space.
- ( jcl-substitution )
- One or more character strings of the form keyword = value ,
enclosed between apostrophes. If you use more than one character string,
separate each string with a comma and enclose the entire list between
a single pair of apostrophes.
Recommendation: Omit the keyword and use the parameters that are provided in the startup procedure.
Usage notes
Command prefix: If your installation has more than one DB2 subsystem, you must define more than one command prefix.
- Log records are processed to the extent that is determined by the conditional restart control record.
- The following values are displayed:
- The relative byte address (RBA) of the start of the active log
- The RBA of the checkpoint record
- The status counts for units of recovery
- The display table for restart unit of work elements
- The restart operation terminates with an abend.
Light restart with ARM: To enable a light restart in an ARM environment, you must code an ARM policy for DB2 and IRLM.
ELEMENT(elementname)
RESTART_METHOD(SYSTERM,STC,'cmdprfx STA DB2,LIGHT(YES)')
ELEMENT(elementname)
RESTART_METHOD(SYSTERM,STC,'cmdprfx S irlmproc')
The element name that DB2 uses is the DB2 data sharing group name and member name concatenated. For example, DSNDB0GDB1G.F
Endless wait during start: The start operation might begin and fail to complete, if the system services address space starts and the database services address space cannot start. If a seemingly endless wait occurs, cancel the system services address space from the console, and check both startup procedures for JCL errors.
Starting members of a data sharing group: To start members of a data sharing group, you must enter a START DB2 command for each subsystem in the group. If it is the first startup of the group, you must start the originating member (the first DB2 that was installed) first.
Examples
-START DB2
-START DB2 MSTR('REGION=6000K')
-START DB2 MSTR('RGN=6000K')
ROUTE MVS1,-DB1G START DB2
ROUTE MVS2,-DB2G START DB2
-START DB2 PARM(VA1AZNS) DECP(DSNHDVA1)