Manual Recovery from a Rollback
Use this procedure to manually recover the DATABridge Span parameter and output files after a DMSII rollback occurs. This procedure is appropriate for situations where a copy of the DATABridge Span parameter file prior to the rollback point is unavailable. DATABridge cannot continue replication until the audit locations in the parameter file are manually corrected using the following instructions.
To manually recover from a rollback
- Run DBInfo in Interactive Mode.
- When prompted, enter the AFN and ABSN of the rollback point and record the information that appears. For example:
Quiet point found on January 30, 2010 @ 09:12:17 at audit location
AFN = 18 ABSN = 17090 SEG = 9 INX = 10
If DATABridge Span sometimes appends updates to data files created by previous replication runs, you must use an AFN and ABSN corresponding to the last time the data files were created from scratch prior to the rollback point. For example, if the rollback point is AFN 18 and ABSN 17090 but the last time the output files were created from scratch was at AFN 17 and ABSN 15885, you need to enter AFN 17 and ABSN 15885 in the Database Info utility.
- Get the DATABridge Span parameter file.
- In the replication status information, enter the values from the DBInfo interactive report for each data set:
Caution: Take precautions to enter the information from the DBInfo interactive report correctly. If the numbers aren't entered correctly, valid updates may be skipped. For example, if the AFN is 100, make sure that you enter 100 and not 102. Entering 102 would prevent you from getting updates from audit files 100 and 101.
- From the Info interactive report, enter the AFN value for File Nbr.
- From the Info interactive report, enter the ABSN value for Aud Block SerialNbr.
- From the Info interactive report, enter the SEG value for Segment Number.
- From the Info interactive report, enter the INX value for Word Index.
- Change the date and time values to all zeros. (If you omit this, the Span accessory will fail with an invalid timestamp error or 0033, which indicates a corrupt audit file because of the invalid timestamp.)
- Change the Mode to 2 if it is not already 2. (If you know that the value was something else, use that value; in most cases, however, the value will be 2. A value of 2 indicates that the data set is ready to be updated.)
An example of the pertinent columns in the replication status information follows.
%Data Rec File Aud Block Segment Word Date Time Mo- Format-Lvl
%-set Type Nbr SerialNbr Number Index YYYYMMDDhhmmss de DMS Client
%---- --- ---- --------- ------- ----- -------------- - ---- ----
%0003 000 0018 0000017090 0000009 00010 0000000000000 2 00000 00000
- When you have finished making the changes to each data set, save the Span accessory parameter file.
- Remove all of the current DATABridge Span output files to prevent the new updates from appending on to the current (yet now obsolete) files.
- Run DATABridge Span as usual.
Caution: If the entered audit location does not exactly match the secondary database, or if you do not know the exact state of the secondary database, there is a possibility of record duplication or loss.