db_recover(1) BSD General Commands Manual db_recover(1)NAMEdb_recoverSYNOPSISdb_recover [-ceVv] [-h home] [-P password] [-t [[CC]YY]MMDDhhmm[.SS]]
DESCRIPTION
The db_recover utility must be run after an unexpected application,
Berkeley DB, or system failure to restore the database to a consistent
state. All committed transactions are guaranteed to appear after
db_recover has run, and all uncommitted transactions will be completely
undone.
The options are as follows:
-c
Perform catastrophic recovery instead of normal recovery.
-e
Retain the environment after running recovery. This option will rarely
be used unless a DB_CONFIG file is present in the home directory. If a
DB_CONFIG file is not present, then the regions will be created with
default parameter values.
-h
Specify a home directory for the database environment; by default, the
current working directory is used.
-P
Specify an environment password. Although Berkeley DB utilities over‐
write password strings as soon as possible, be aware there may be a
window of vulnerability on systems where unprivileged users can see
command-line arguments or where utilities are not able to overwrite
the memory containing the command-line arguments.
-t
Recover to the time specified rather than to the most current possible
date. The timestamp argument should be in the form [[CC]YY]MMD‐
Dhhmm[.SS] where each pair of letters represents the following:
CC
The first two digits of the year (the century).
YY
The second two digits of the year. If "YY" is specified, but "CC"
is not, a value for "YY" between 69 and 99 results in a "YY" value
of 19. Otherwise, a "YY" value of 20 is used.
MM
The month of the year, from 1 to 12.
DD
The day of the month, from 1 to 31.
hh
The hour of the day, from 0 to 23.
mm
The minute of the hour, from 0 to 59.
SS
The second of the minute, from 0 to 61.
If the "CC" and "YY" letter pairs are not specified, the values
default to the current year. If the "SS" letter pair is not specified,
the value defaults to 0.
-V
Write the library version number to the standard output, and exit.
-v
Run in verbose mode.
In the case of catastrophic recovery, an archival copy -- or snapshot --
of all database files must be restored along with all of the log files
written since the database file snapshot was made. (If disk space is a
problem, log files may be referenced by symbolic links). For further
information on creating a database snapshot, see Archival Procedures. For
further information on performing recovery, see Recovery Procedures.
If the failure was not catastrophic, the files present on the system at
the time of failure are sufficient to perform recovery.
If log files are missing, db_recover will identify the missing log
file(s) and fail, in which case the missing log files need to be restored
and recovery performed again.
The db_recover utility uses a Berkeley DB environment (as described for
the -h option, the environment variable DB_HOME, or because the utility
was run in a directory containing a Berkeley DB environment). In order to
avoid environment corruption when using a Berkeley DB environment,
db_recover should always be given the chance to detach from the environ‐
ment and exit gracefully. To cause db_recover to release all environment
resources and exit cleanly, send it an interrupt signal (SIGINT).
The db_recover utility exits 0 on success, and >0 if an error occurs.
ENVIRONMENT
DB_HOME If the -h option is not specified and the environment variable
DB_HOME is set, it is used as the path of the database home, as
described in DB_ENV->open.
SEE ALSOdb_archive(1), db_checkpoint(1), db_deadlock(1), db_dump(1), db_load(1),
db_printlog(1), db_stat(1), db_upgrade(1), db_verify(1)Darwin December 3, 2003 Darwin