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mysqlbkup

Project on Github

Lightweight MySQL backup script to backup all your MySQL databases every night.

In a matter of minutes you can setup nightly backups of your MySQL databases on
any Linux server with mysqldump and standard GNU utilities.

Instructions

  1. Download the script, I recommend installing it somewhere like /usr/local/bin
  2. Set permissions & ownership accordingly
  3. Configure database and backup parameters (see Configuration below)
  4. Setup a CRON job (see CRON below)

Configuration

Database Settings

$USER – The database username

$PASS – The database password

$HOST – The database host (default 127.0.0.1)

Backup Settings

$BACKUP_DIR – The directory where backups are written

$MAX_BACKUPS – Number of backups per database (default 3)

Compression Settings

$BKUP_BIN – The binary used to compress mysqldump files

$BKUP_EXT – The extension used for compressed backup files

The default compression program is gzip and the default extension is .gz.
You may change these to any program and extension you wish, in which case take note the various examples below will have different extensions accordingly.

Database filter Setting

$DB_EXCLUDE_FILTER – Filter to exclude databases from the backup (see Excluding databases from backup below)

CRON

The cron is simple, just schedule it once per day.

Here we redirect STDOUT to a log file and STDERR to a separate log file.

## mysql backups --------------------------------------
1 2 * * * /usr/local/bin/mysqlbkup.sh 1>> /var/log/mysqlbkup.log 2>>/var/log/mysqlbkup-err.log

What it does

The script will create directories beneath $BACKUP_DIR, named after the database.
Beneath there, gzip files are created for each day the database is backed up. There
will be at most $MAX_BACKUPS backup files for each database.

/var/db-backups/my_db/
2013-02-10-my_db.sql.gz  2013-02-11-my_db.sql.gz  2013-02-12-my_db.sql.gz

Retrieving a backup

Just drill down into the directory of the database you desire to restore
(or copy to another location). Take the prior example for instance. Suppose you wish to
unpack it in your home directory and view the contents of the database. You simply copy
and gunzip the file.

# Copy the database backup to your home directory
cp /var/db-backups/my_db/2013-02-12-my_db.sql.gz ~
# Unpack the database
gunzip ~/2013-02-12-my_db.sql.gz

At this point ~/2013-02-12-my_db.sql is available as a normal plain text SQL file.

Restoring a backup

Restore an unzipped SQL file:

mysql -h [host] -u [uname] -p[pass] [dbname] < [backupfile.sql]

Restore a zipped SQL file:


gunzip < [backupfile.sql.gz] | mysql -h [host] -u [uname] -p[pass] [dbname] [/bash]

Excluding databases from backup

The filter string is space-separated list of entries that indicate databases to exclude. You may do an exact match such as

DB_EXCLUDE_FILTER='my_db'

By default excluding filter entries use BASH pattern matching. So you might test for a prefix in the database name with a filter like this

DB_EXCLUDE_FILTER='wp_*'

If BASH pattern matching isn’t good enough for some reason, you may alternatively use POSIX regular expressions by prefixing your entry with a tilde. For example

DB_EXCLUDE_FILTER='~.*_test'

Again, these are space-separated entries and you can mix and match, so to include all 3 of the examples in one filter

DB_EXCLUDE_FILTER='my_db wp_* ~.*_test'

Requirements

mysql & mysqldump as well as GNU versions of the following programs
date, gzip, head, hostname, ls, rm, tr, wc

If you override gzip using the $BKUP_BIN option, the binary you choose must be installed and will be checked during script execution.

Dry Run

To test the script’s configuration you may invoke it passing ‘dry’ as the first argument.

mysqlbkup.sh dry