NAME
mysql-backup
SYNOPSIS
Please see MySQL::Backup thread in module-authors mailing list at
perl.org <module-authors@perl.org>. I just copied everything from my
MySQL::Backup project into this namespace as a result of that
discussion. I'll be breaking out the backup management and mysql
specific parts and getting this dist passing basic tests again ASAP.
shell% mysql-backup /path/to/mysql-backup.conf
new() constructor for Backup::Config object
Gets all config information from the config file and also
gets some data and values from the database itself. Then
stores all this information as attributes in
Backup::Config object. All attributes are accessed by
method $obj->section(attr_name) where attr_name should be replaced
by the name of the attribute which value is requested.
To set the value, call $obj->section->attr_name($val)
All accessors and mutators are created by AUTOLOAD.
_get_program_path()
Gets a name of a program and returns the full path to it.
If the path contains anything than slashes, alhpanumeric charactes
and underscores and dashes undef is returned.
usage()
Prints an usage message for the program on the screen and then exits.
run()
This is where most of the work in the program is done.
It logs some messages to the log file and invokes the subroutines
for database backup and log backup and rotation.
_get_process_list()
Returns a list of all mysql processes running currently on the server.
Gets the processlist from dbms and print it to the LOG the fields are
as follows:
Id User Host db Command Time State Info
The assumption is that these fields will not change. It's hard to make
a dynamic script because LISTFIELDS works only on tables, and retrieval
to a hash does not preserve the order of the fields.
log_messages
Logs all messages accumulated so far to a log file
which name is specified in the config variable log_file.
_test_create_dirs
Test for the existence and writeability of specified directories.
If the directories do not exist, attempt to create them. If unable
to create writeable directories, fail with error.
_rotate_error_log()
The mysql error logs don't operate the same way as the other logs.
As of mysql 4.0.10, every flush-logs command will cause the error log
to rotate to a file with an "-old" suffix attached. This is
regardless of the file's size. Mysql shutdown/startup will *not*
rotate the error log to the -old file. Any previous -old file
is deleted.
This function attempts to restore some sanity to how mysql treats
the error log. Call this function after the flush-logs command.
We will take new -old file and append it to the end of our own file,
(different name) and delete the -old file. We'll then call the usual
_rotate_generic_log function on it.
_cycle_bin_logs()
Issues command to mysqld to finish writing to the current binary
update log and start writing to a new one. We then push all of
the bin-logs (except for the newest one) into [dump_dir]/00/.
The flush logs command causes mysqld to close the old (already renamed)
general query and slow query logs and reopen the logs of the usual
file name. It also causes mysqld to flush the binary update log and
begin writing to a new binlog file. It does not affect the error
log, only a restart of mysqld will start a new error log.
The flush hosts command will clean up the hosts cache.
_backup_databases()
Backup all databases on the server DBMS which are mentioned
explicitly or as a pattern in the [included-databases] section
in the config file.
This function will dump all specified databases to .sql.gz files
in the directory [dump_dir]/new/. If there were no errors during
backup, _rotate_dump_dirs will then rename it [dump_dir]/00/.
If this function encounters errors during backup, the partial dumps
to [dump_dir]/new/ will remain until the next time this function is
executed. At that time, the contents of [dump_dir]/new/ will be
destroyed and new dumps will be placed there.
At no time are binary update logs ever placed in [dump_dir]/new/.
Return with the number of errors encountered during backup.
_rotate_dump_dirs()
The dump directories contain output from both the full, weekly mysql
dump as well as the incremental binary update logs that follow the
dump (possibly multiple binlogs per day). Rotate these directory
names to conform to convention:
[dump_dir]/00/ - most recent dump
[dump_dir]/01/ - next most recent
...
[dump_dir]/_NN/ - oldest
Where N is [dump_copies] - 1 (in the config file). [dump_dir]/new/
is a temporary directory created from _backup_databases. This will
be renamed 00/, 00/ will be renamed 01/, and so on.
_tidy_dump_dirs()
The dump directories contain output from both the full, weekly mysql
dump as well as the incremental binary update logs that follow the
dump (possibly multiple binlogs per day). Sometimes a user might
delete a directory between backup runs (particularly if it has bad
dumps).
This function is intended to be run before backups start. It will
Attempt to make directory names to conform to convention:
[dump_dir]/00/ - most recent dump
[dump_dir]/01/ - next most recent
...
[dump_dir]/NN/ - oldest
If there are missing directories, _tidy_dump_dirs will create a
directory to take its place, such that 00/ should always exist
and there should be no gaps in the numbering of old directories. In
other words, N+1 should be the total number of directories in [dump_dir].
If there are no gaps to begin with, _tidy_dump_dirs does not rename
anything.
This function will also delete any xx directories that exceed the
[dump_copies] config variable.
It will never touch [dump_dir]/new/. It will never modify the contents
of any of these subdirectories (unless its deleting the whole subdir).
It will create [dump_dir] and [dump_dir]/00/ if they do not exist.
error()
Logs all the errors so far to a log file then
sends an email and exits.
send_email_notification()
Sends the data from the 00 run of the program
which gets stored in the log file by email. The exact
behaviour for this subroutine is controlled by the
varibles in [mail-setup] section in the config file
INSTALLATION
To install this module type the following:
perl Makefile.PL
make
make test
make install
DEPENDENCIES
This module requires these other modules and libraries:
Mail::Sendmail # if you want email reports
YAML
Sys::Hostname
File::Copy
File::Path
DESCRIPTION
Manages rotation of mysql database logs and database backups. Reads
information on which databases to back up on what days fo the week from
the configuration file. If no file is specified, it will look for one at
/etc/mysql-backup.conf. If no configuration file is found program will
exit with a failure.
This program assumes a MySQL 4.0.x server that is at least 4.0.10. It
will likely work with current 1.23.xx server, but that has not been
tested. Please let the maintainers know if you use this tool succesfully
with other versions of MySQL or Perl so we can note what systems it
works with.
The expected usage of this program is for it to be run daily by a cron
job, at a time of day convienient to have the backups occur. This
program uses the administrative tools provided with MySQL (mysqladmin
and mysqldump) as well as gzip for compression of backups.
Every time this program is run it will flush the MySQL logs. The binary
update log will be moved into /path/to/dump/dir/00. Error log and slow
query log files are rotated only if they exceeded the size limit
specified in the confguration file.
If it is run on a day when full database backups are specified, then all
databases specified in the config file are dumped and written to the
directory specified in dump_dir variable in the config file. If there
are no problems with this operation, previous full backups from
dump_dir/00 are moved to directory dump_dir/01 and all the files in
dump_dir/01 (full database backups and log files) are deleted from it or
moved to dump_dir/02 etc. to the archival depth specified in the config
file. This way there always [dump_copies] full database backups - one in
00/ and [dump_copies]-1 in the xx directories.
Detailed information about the different configuration parameters can be
found in the comments in the configuration file
log-slow-queries log-long-format log-bin
OPTIONS
logfile
Filename for logging backup proceedure. Overrides conf file.
add_databases
Additional databases to back up. These will be backed up *in
addation* to any databases specified in the conf file. Note - this
adds databases to the list of those to be backed up. If the program
is being run on a day when database backups are not scheduled, the
extra databases specified will not be backed up.
backup
If present this option forces full database backups to be done, even
if not normally scheduled.
help
Outputs this help file.
d ** NOT IMPLIMENTED **
Turn on debugging. Optionally takes a filename to store debugging
and any error messages to.
v ** NOT IMPLIMENTED **
Increases debugging vebosity. If three or more v's provided (-v -v
-v) than program will exit on warnings.
TO DO
Impliment debugging output options.
HISTORY
0.8 First functional release.
SEE ALSO
mysql-backup.conf
AUTHOR
Sean P. Quinlan, <sean@quinlan.org>
Original version by Stefan Dragnev, <dragnev@molbio.mgh.harvard.edu>
with contributions from Norbert Kremer,
<kremer@molbio.mgh.harvard.edu<gt> and Danny Park,
<park@molbio.mgh.harvard.edu.<gt>
COPYRIGHT AND LICENSE
Copyright (C) 2004 by Sean P. Quinlan & Stefan Dragnev
This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself, either Perl version 5.8.3 or, at
your option, any later version of Perl 5 you may have available.