NAME
db4.6_archive - Find unused log files for archiving purposes
SYNOPSIS
db4.6_archive [-adlsVv] [-h home] [-P password]
DESCRIPTION
The db4.6_archive utility writes the pathnames of log files that are no
longer in use (for example, no longer involved in active transactions),
to the standard output, one pathname per line. These log files should
be written to backup media to provide for recovery in the case of
catastrophic failure (which also requires a snapshot of the database
files), but they may then be deleted from the system to reclaim disk
space.
OPTIONS
-a Write all pathnames as absolute pathnames, instead of relative
to the database home directories.
-d Remove log files that are no longer needed; no filenames are
written. Automatic log file removal is likely to make
catastrophic recovery impossible.
-h Specify a home directory for the database environment; by
default, the current working directory is used.
-l Write out the pathnames of all the database log files, whether
or not they are involved in active transactions.
-P Specify an environment password. Although Berkeley DB utilities
overwrite 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.
-s Write the pathnames of all the database files that need to be
archived in order to recover the database from catastrophic
failure. If any of the database files have not been accessed
during the lifetime of the current log files, db4.6_archive will
not include them in this output.
It is possible that some of the files to which the log refers
have since been deleted from the system. In this case,
db4.6_archive will ignore them. When db4.6_recover is run, any
files to which the log refers that are not present during
recovery are assumed to have been deleted and will not be
recovered.
-V Write the library version number to the standard output, and
exit.
-v Run in verbose mode, listing the checkpoints in the log files as
they are reviewed.
Log cursor handles (returned by the DB_ENV->log_cursor method) may have
open file descriptors for log files in the database environment. Also,
the Berkeley DB interfaces to the database environment logging
subsystem (for example, DB_ENV->log_put and DB_TXN->abort) may allocate
log cursors and have open file descriptors for log files as well. On
operating systems where filesystem related system calls (for example,
rename and unlink on Windows/NT) can fail if a process has an open file
descriptor for the affected file, attempting to move or remove the log
files listed by db4.6_archive may fail. All Berkeley DB internal use
of log cursors operates on active log files only and furthermore, is
short-lived in nature. So, an application seeing such a failure should
be restructured to close any open log cursors it may have, and
otherwise to retry the operation until it succeeds. (Although the
latter is not likely to be necessary; it is hard to imagine a reason to
move or rename a log file in which transactions are being logged or
aborted.)
The db4.6_archive 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, db4.6_archive should always be given the chance to detach
from the environment and exit gracefully. To cause db4.6_archive to
release all environment resources and exit cleanly, send it an
interrupt signal (SIGINT).
The DB_ENV->log_archive method is the underlying method used by the
db4.6_archive utility. See the db4.6_archive utility source code for
an example of using DB_ENV->log_archive in a IEEE/ANSI Std 1003.1
(POSIX) environment.
The db4.6_archive 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.
AUTHORS
Sleepycat Software, Inc. This manual page was created based on the HTML
documentation for db_archive from Sleepycat, by Thijs Kinkhorst
<thijs@kinkhorst.com>, for the Debian system (but may be used by
others).
28 January 2005