Section: BerkeleyDB Utilities (1)
Updated: 06 December 2016
db_log_verify - Verify log files of a database environment
[-cNvV] [-h home-to-verify
] [-H temporary-home
] [-C cache-size
] [-e end-lsn
] [-s start-time
] [-z end-time
] [-D database-name
utility verifies the log files of a specific database environment.
This utility verifies a specific range of log records,
or changed log records of a specific database.
- -C cache-size
Specify the cache size (in megabytes) of the temporary database environment internally
used during the log verification.
- -b start-lsn
Specify the starting log record (by lsn) to verify.
Specify whether to continue the verification after an error is detected.
If not specified, the verification stops when the first error is detected.
- -D database-name
Specify a database name. Only log records related to this database are verified.
- -d database-filename
Specify a database file name. Only log records related this database file are verified.
- -e end-lsn
Specify the ending log record by lsn.
- -h home-to-verify
Specify a home directory of the database environment whose log is to be verified.
- -H temporary-home
Specify a home directory for this utility to create a temporarily database environment
to store runtime data during the verification.
It is an error to specify the same directory as the -h option. If this directory is not specified,
all temporary databases created during the verification will be in-memory,
which is not a problem if the log files to verify are not huge.
Do not acquire shared region mutexes while running. Other problems, such as potentially
fatal errors in Berkeley DB, are ignored as well. This option is intended only for debugging errors,
and should not be used under any other circumstances.
- -P password
Specify an environment password. Although Berkeley DB utilities overwrite
password strings as soon as possible, 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.
- -s start-time
Specify the starting log record by time. The time range specified is not precise because
the lsn of the most recent time point is used as the starting lsn.
Write the library version number to the standard output and exit.
Enable verbose mode to display verbose output during the verification process.
- -z end-time
Specify the ending log record by time. The time range specified is not precise because
the lsn of the most recent time point is used as the ending lsn.
To specify a range of log records, you must provide either an lsn range or a time range.
You can neither specify both nor specify an lsn and a time as a range.
If the log footprint is over several megabytes, specify a home directory and a big cache size
for log verification internal use. Else, the process' private memory may be exhausted
before the verification completes.
The db_log_verify utility does not perform the locking function, even in Berkeley DB
environments that are configured with a locking subsystem.
All errors are written to stderr, and all normal and verbose messages are written to stdout.
The db_log_verify 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_log_verify should always be given the chance to
detach from the environment and exit gracefully. To cause db_log_verify
to release all environment resources and exit cleanly, send it an
interrupt signal (SIGINT).
utility exits 0 on success, and >0 if an error occurs.
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
If the application(s) that use the environment make use of the DB_ENV->set_lg_dir
method, then in order for this utility to run correctly, you need a DB_CONFIG
file which sets the proper paths using the set_lg_dir configuration parameter.