Online Rollback Technical Concepts

Method

The online recovery process uses a combination of commitment control and user journals to mark the beginning and end of transactions.  The online programs that require consistent updates to multiple files use commitment control if transactions will not exceed 1,024 updates.  Beginning (BE) and ending (EN) journal entries are used if transactions could exceed 1,024 updates.  The 1,024-transaction limit is imposed by the  Commitment Control Facility of the operating system.

Processing

The Online Rollback Control program (RM200C) provides control for the online recovery stream.  The stream flow is as follows:

1.   The Recovery Management Online Transaction Check program (RM200E) is called. This program is described in detail in the Program Descriptions section.

a.   The program checks the Recovery Management Sync Point File for failed online transactions.  The Sync Point File contains the beginning (BE) and ending (EN) journal entries that mark the boundaries for each transaction.  This file also contains the recovered error (RE) journal entries that signify that a transaction has been recovered previously.

b.   Any transaction that is found to have failed is placed into the Online Rollback Limit File (RM200AP).

2.   The next step of the rollback procedure is determined.

a.   If no failures are detected, processing continues at step 7.

b.   If failures are detected, the Failed Online Transaction List Screen is displayed with a list of failed transactions.

(1)  If F13 (Return Without Recovery) is pressed, processing continues at step 7.

(2)  If F22 (Continue Recovery) is pressed, processing continues at step 3.

3.   The Recovery Management Online Rollback Extract program (RM220C) is called.

a.   The program displays journal entries for the online transactions that were determined to have failed (these are found by reading RM200AP).

b.   These entries are placed in the Online Rollback File (RMJRNLP).  There are three types of journal entries that will be rolled back:  update (UB), add (PT), and delete (DL).

4.   The Recovery Management Online Remove Journal Change program (RM240C) is called.

a.   The program removes journal changes for each entry found in the Online Rollback File (RMJRNLP).  In online processing, these changes are removed one at a time for two reasons:  a given range of the journal may contain journal entries for several different jobs; and each online job can call more than one program, of which only one might have failed.

b.   RM240C calls the Recovery Net Change Processing program (RM242C), which processes the net changes of failed transactions.  RM242C calls the Recovery Management Net Change Processing program (RM220E), which actually applies the net change.

5.   The Recovery Management Online Send Recovered Error Message program (RM260C) is called.  The program writes a recovered error (RE) journal entry for each failed online transaction that is found in RM200AP.

6.   The Recovery Management Online Rollback Print program (RM280L) is called.  This program is described in detail in the Program Descriptions section.  The program reads the Online Rollback File (RMJRNLP) and produces a report of all rolled back journal entries by file.

7.   The Async Work File Purge program (RM290P) is called.  This program is described in detail in the Program Descriptions section.

a.   The Async Message Queue (MPASYNMSGQ) is compared to the asynchronous transaction files for Product Structure Copy, Routing Copy, Manufacturing Order Maintenance, Order Picking, and SIR processing.

b.   Transactions from the work files that have no corresponding entries in the message queue are deleted.  All other transactions are left in the work files.

8.   The Multi-line Receipt Async Recovery program (RM292P) is called.

9.   The Purchasing Lock Release program (RM295P) is called.  This program is described in detail in the Program Descriptions section.

a.   The program reads locked records that are on the logical Locked Purchase Order File (RM295BL), the logical Locked Item/Vendor Relationship (RM295CL), the logical Locked Quotation (RM295DL), the logical Locked Requisition (RM295EL), and the logical Locked Purchase Order Receipts (RM295FL).

b.   All locked records are unlocked.

10.  The Unlock SYNCHRO File's Records program (RM298P) is called.  This program is described in detail in the Program Descriptions section.

a.   The program reads the 17 Recovery Management Synchro logical files (RM298AL through RM298 QL) as well as the Synchro Shipping/Billing Transaction Logical File (GA270AL).

b.   All locked records are unlocked.

11.  The Configurator Locks Release program (RM294P) is called.  This program is described in detail in the Program Description section.

a.   The program reads the Rules Logically Locked File (RM294AL).  The lock field is changed to off and file is updated.  If the update is successful, the rule information is printed.  If an error occurred, an error message is sent to the report.

b.   The program reads the Matrixes Logically Locked File (RM294BL).  The lock field is changed to off and file is updated.  If the update is successful, the matrix information is printed.  If an error occurred, an error message is sent to the report.

12.  The Customer Master File Lock Release program (RM296P) is called.  This program is described in detail in the Program Descriptions section.

a.   The program reads the locked customer master file records that are on the logical Locked Customer Master Records File (RM296AL).

b.   All locked records are unlocked.

13.  The customer order work files (IC180AP and IC190AP) are cleared.

14.  The requirements review work file member (RP800AP) is removed.

15.  The time-phased part availability work file member is removed.

16.  The Recovery Management work files (RMJRNLP and RMSYNCP) are cleared, and processing ends.  The Online Transactions Pending Completion program (RM297L) is called.  This program is described in detail in the Program Descriptions section.

a.   The program reads the locked sales order header, records, incomplete invoice header records, and unprocessed shipping work file records.

b.   The report is printed.

17.  The Remove Workfile Members program (RM290C) is called.