Dump all MySQL databases to a location of your choice. I run this as a backup_script from rsnapshot.

This requires the following .my.cnf in the home directory of the user the script runs as (root, when being run from rsnapshot). As it contains an important password, permissions on this file should be 600 (-rw-------).

[client]
user     = root
password = YOUR_MYSQL_ROOT_PASSWORD

#!/bin/bash -e
###########################################################
# Back up MySQL databases
###########################################################

PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
PATH="$PATH:/usr/local/mysql/bin"

# My config
#BACKUP_DIR="."

BACKUP_DIR=""

# Do not backup these databases
IGNORE="test"

# Get list of all databases
DB_LIST=`mysql -Bse 'show databases'`

for db in $DB_LIST; do

        # set skip variable
        skip=0

        if [ "$IGNORE" != "" ]; then
                for i in $IGNORE; do
                        [ "$db" == "$i" ] && skip=1 || :
                done
        fi

        if [ "$skip" == "0" ]; then
                mysqldump $db | gzip -9 > $BACKUP_DIR/$db.sql.gz
        fi

done

exit 0