Rollback function

Roll back corrupted databases.

The Rollback function is a command-line version of Automatic Backward Recovery for IMS databases. This function rolls back all corrupt databases. When complete, the output list file shows the results of the rollback.

Syntax

mfims imsdbu ROLB * TLOG(tlogName) 
     [[NO]CLS] 
     [ECHO(keyword,msglvl,stoplvl
     [[NO]INI(filespec)]
     [[NO]LIST(filespec)]
     [LISTOPEN(disp)]
     [[NO]LOG(filespec)]

Parameters

TLOG
Specifies the name of the TLOG file to be used for rollback.
Default: None
Sub-parameter
tlogName The name of the rollback TLOG file.
Syntax Rules
  1. tlogName can include a drive and/or directory if required. If you do not specify a drive or directory, IMSDBU looks for the specified file in the current directory.
CLS
Clears the screen before starting the utility. NOCLS prevents the initial clear screen and can be helpful when you are running a series of utilities in a command file.
Default: NOCLS
ECHO
Controls the display of and interaction with the messages displayed by IMSDBU.
Default: ECHO(MSGS,4,8)
Sub-parameters
keyword The category of information displayed. One of the following:
ALL
Always displays processing messages, input source or detail information and the ending message. Warning and error messages are displayed and stop for user input if the message level is equal to or greater than the msglvl and stoplvl values.
MSGS
Always displays processing messages and the ending message. No source or detail information is displayed. Warning and error messages are displayed and stop for user input if the message level is equal to or greater than the msglvl and stoplvl values.
ERREND
Always displays the utility ending message. Warning and error messages are displayed and stop for user input if the message level is equal to or greater than the msglvl and stoplvl values.
ENDMSG
Displays ending message only if the utility ending return code is equal to or greater than msglvl. A "Press any key to continue" message is displayed and stops for input if the utility ending return code is equal to or greater than the stoplvl. Enter a msglvl and/or stoplvl value of zero to display and/or stop on every ending message.
COND
Both the warning/error and ending messages are conditional on the msglvl and stoplvl values. Warning and error messages are displayed and stop for user input if the message level is equal to or greater than the msglvl and stoplvl values. The ending message is displayed if the ending return code is equal to or greater than msglvl. You see the message "Press any key to continue" which requires input if the utility ending return code is equal to or greater than the stoplvl.
ERRORS
You see warning and error messages which require input if the message level is equal to or greater than the msglvl and stoplvl. You do not see the ending message.
msglvl A value from 4 through 20 to indicate the severity of messages to display.1
stoplvl A value from 4 through 20 to indicate the severity of messages to stop for user input. 1
1 Can take the following values:
Value Category Example Cause
4 General warning message A minor coding error in DBD source which DBDGEN can make an assumption about and continue.
6 IMS specific warning message A warning that a keyword or statement is not supported and is ignored - processing can continue.
8 General severe error An incorrect coding in DBD source which cannot be compensated for, such as 'no DBD statement'.
10 IMS Option specific severe error An unsupported feature was defined which cannot be compensated for, such as 'Exceeded some maximum'.
12 Severe error - possible temporary condition A temporary I/O error such as a 'file locked' or 'database locked' status.
16 Severe error- permanent - likely installation problem A permanent I/O error, such as an invalid data set name or member name, was input to a utility or an environment variable is not set correctly.
20 Severe error - permanent An unrecoverable I/O error or some other unexpected error.
INI
Specifies the default directives file.
Default: None
Sub-parameter
filespec The name and location of the .INI file containing directives that override the IMSDBU programmed defaults.
Syntax Rules
  1. filespec can include a drive and/or directory if required. If you do not specify a drive or directory, IMSDBU looks for the named .INI file in the current directory.
  2. Directives listed in the .INI file override the IMSDBU programmed defaults.
  3. Directives entered on the command line or interactive screen override directives in the .INI file.
  4. Specifying NOINI prevents any .INI file from overriding the programmed defaults.
  5. If you specify an .INI file that does not exist, the programmed default directives are used as if NOINI were specified.
General Rules
  1. An .INI file is an ASCII text file containing a heading, [IMSDBU] on line 1, starting in column 1, followed by a list of mfims imsdbu directives; one directive per line. A line is terminated by a return or an end-of-file. Comment lines are indicated by an asterisk (*) or semi-colon (;) in column 1. For example: 
    [IMSDBU]
PROGRESS(1000)
;use local log
LOG(C:\MYDIR\MYDB.LOG)
LIST
Controls the location and name of the detail listing file, which includes rollback statistics.
Default: ROLLBACK(*.LST)
Sub-parameter
filespec The name and location to use for the listing file.
Syntax Rules
  1. filespec can include a drive and/or directory if required. If you do not specify a drive or directory, IMSDBU creates the listing file in the current directory.
  2. filespec can include a drive and/or directory if required. If you do not specify a drive or directory, IMSDBU creates the listing file in the current directory.
  3. NOLIST suppresses the creation of the listing file.
  4. To specify a path, you can use the convention of placing a dollar sign ($) in front of the name of an environment variable that represents a path. For example, LIST($ENVVAR\*.DOC) creates a list file of dbdname.DOC in the directory named by the ENVVAR environment variable.
  5. Specifying LIST(*.LST) or LIST(*.RPT) causes the listing file to be created in the project listing directory.
  6. If no path is specified, the listing file is created in the current directory.
  7. If you specify the base name of filespec as an asterisk (*), it is replaced by the DBD name; this allows IMSDBU to provide separate reports for functions that can operate on multiple databases. It also assists in maintaining historical detailed reports by DBD name.
  8. Specifying LIST with no filespec is equivalent to specifying LIST(*.LST).
LISTOPEN
Controls the open disposition of the detail listing file.
Default: LISTOPEN(NEW)
Sub-parameter
disp The disposition to use. One of:
NEW
Creates a new listing file or overwrites an existing one.
MOD
Appends the list output to an existing file or creates a new listing if one does not exist. MOD allows you to maintain a detailed historical record of database functions.
Syntax Rules
  1. LISTOPEN is ignored when NOLIST is specified.
LOG
Specifies the IMSDBU activity log, which shows the ending message status for each function.
Default: LOG(IMSDBU.LOG)
Sub-parameter
filespec The name and location of the file to use as the IMSDBU activity log.
Syntax Rules
  1. filespec can include a drive and/or directory if required. If you do not specify a drive or directory, the listing is created in the current directory.
  2. Specifying NOLOG suppresses the log file output.
General Rules
  1. The log file is created if it does not exist.
  2. The log file is historical with the most recent entries written to the end of the file.
  3. As the log file grows in size over time, it might require deletion periodically.
Parent topic: mfims imsdbu functions
Related concepts
IMS Database Automatic Backward Recovery
TLOG Files
Automatic Backward Recovery Process
Invoking Backward Recovery from JCL
Related reference
TLOG