TurboIMAGE/XL Database Management System Reference Manual MPE/iX V6.5 (30391-90011)

Chapter 7 371
Logging and Recovery
The Mirror Database
command and RESTART from the previous STOP point.
To start the recovery process again, find out why the databases are not in RESTART mode
and try to correct the problem. If the problem cannot be corrected, take either of the
following steps:
• Go to the previous STOP point and use the databases and RESTART file stored to restart
roll-forward recovery, or
• ABORT the current RESTART process. Disable user access on the primary databases and
make a copy for the secondary system. Begin a new logging process on the primary
system and a new recovery process on the secondary system.
If all databases are found, and they are in RESTART mode, then the time stamps in the
database root file are compared to the time stamp in the RESTART file. If they do not agree,
the following DBRECOV error message is printed:
RESTART TIME STAMPS DON'T AGREE WITH DATABASE TIME STAMPS
This indicates incompatibility of the RESTART file and the databases. The user is returned
to the MPE/iX prompt. Use the same steps given above to recover from a time stamp error.
After all the compatibility checks have passed, DBRECOV prints a table of the databases to
be recovered:
DATABASE(S) TO BE RESTARTED:
base1.group.acct
base2.group.acct
.
.
.
The user is then prompted to confirm the restart:
CONTINUE WITH RECOVERY (N/Y)?
Respond Y or YES to continue, or type N or NO (or press carriage return) to return to the
STOP point. If any of the databases cannot be opened during recovery, an MPE/iX file error
is returned and DBRECOV RESTART is terminated. When this happens, go back to the
previous STOP point and use the databases, log files, and the RESTART file to RESTART
recovery. If a log file in the log set has been damaged or the user cannot RESTART recovery
for any reason, ABORT the current recovery process and begin the mirror database process
again. When the recovery process terminates, the user is returned to the MPE/iX prompt.
Two ways of continuing to mirror the databases are listed here:
• Go to the previous STOP point and use the databases, log files, and RESTART file stored
to restart roll-forward recovery. This option is not valid if there is a missing or damaged
log file.
• Disable user access on the primary databases and make a copy for the secondary
system. Begin a new logging process on the primary system and a new recovery process