New Zealand Linux

Everyone wants to back up right? Well you will once you have totally lost the last years worth of work on a website and somebody breaks things severely!

Heres a quick and nasty backup HOWTO.

Database Dumps

mysqldump -u root -p mydatabase > mydatabase.sql

This dumps a database into a file, you can modify this to dump it offsite using ssh with this command.

su postgres -c "pg_dumpall" > pgdatabase.psql

If you use postgres you can change this to something like this

mysqldump -u root -p mydatabase > mydatabase.sql | ssh username@backup.comain.com “dd of=mydatabase.sql”

If you want to dump the entire database you can use

mysqldump -A -u root -p >entiredatabase.sql

This may take some time. To put this in a shell script and dump multiple copies and keep track of things you can use something similar to this

date=`date +%m-%h-%Y`

mysqldump -A -u root -p >${date}-fulldatabase.sql

This will expand to dump it into something like

06-Jun-2009-fulldatabase.sql

File Backup

FTP

To run a regular interactive FTP session:

lftp -u 'username,password' backup.yourdomain.com

To backup one or more files:

lftp -u 'username,password' backup.yourdomain.com -e "set ftp:ssl-protect-data true; mput /local/dir/files* /remotedir; exit"

You need to set ftp:ssl-protect-data else you will not be able to store the file. If you want to make this a default option, add it to the lftp.conf file. e.g. :

grep -qai "set ftp:ssl-protect-data true" /etc/lftp.conf || echo "set ftp:ssl-protect-data true" >> /etc/lftp.conf

To restore a file from the FTP server to your Machine:

lftp -u 'username,password' backup.yourdomain.com -e "set ftp:ssl-protect-data true;mget /remotedir/files* -O /localdir; exit" .

The -O option is not required it you wish to store to the current local directory.

To mirror a whole directory to the FTP server:

lftp -u 'username,password' backup.yourdomain.com -e "set ftp:ssl-protect-data true;mirror --reverse /local/dir/name remotedirname; exit" .

--reverse means that the ‘mirroring’ is going in the reverse direction than ‘normal’. i.e. from your server to the backup server. If you run man lftp there are a few other options to choose from. e.g. --delete to delete files on the backup server that do not exist locally. Or --continue to continue a mirror job. Or --exclude files to exclude certain files from the transfer.

To restore a whole directory from the FTP server to your machine:

lftp -u 'username,password' backup.yourdomain.com -e "set ftp:ssl-protect-data true;mirror remotedirname /local/dir/name;exit"

To create a nightly cronjob that uploads a directory to the backup FTP server, create a /etc/crond.daily/ftpbackup file like this:

#!/bin/bash
lftp -u 'username,password' backup.yourdomain.com -e "set ftp:ssl-protect-data true;mirror --reverse /local/dir/name remotedirname;exit" > /dev/null

Run

chmod +x /etc/cron.daily/ftpbackup .

Then check the files have been mirrored as you expect the next day.

Rsync

Rsync is a better option in some ways as it checks the MD5 of files and updates them if they are out of date, rather than re-copying the entire lot. Short but easy shell script to copy things over

#!/bin/bash
EXCLUDE=” –exclude *.tmp \
–exclude *.temp”
USER=username
HOST=backup.domain.com
BACKUPPATH=/backups

rsync –archive -vv –rsh=ssh $EXCLUDE $USER@$HOST:/etc/ $BACKUPPATH/$HOST/etc

Rdiff-backup

This is better again than rsync as it does versioning control and only backs up the difference in files.

To backup files

rdiff-backup /some/local-dir hostname.net::/whatever/remote-dir

To restore

rdiff-backup --restore-as-of now host.net::/remote-dir/file local-dir/file
rdiff-backup -r now host.net::/remote-dir/file local-dir/file

The -r command is the same as –restore-as-of

The main advantage of rdiff-backup is that it keeps version history. This command restores host.net::/remote-dir/file as it was 10 days ago into a new location /tmp/file .

rdiff-backup -r 10D host.net::/remote-dir/file /tmp/file

Other acceptable time strings include 5m4s (5 minutes and 4 seconds) and 2002-03-05 (March 5th, 2002). For more information, see the TIME FORMATS section of the manual page.

More examples can be found at http://www.nongnu.org/rdiff-backup/examples.html

This tutorial was compiled from several others, and props go out to http://rimuhosting.com and http://www.howtoforge.com