[SOLVED] help with shell script

[drumhrd]

ok so I have no idea how to go about building this shell script.

 

I have an external HDD on my web server.  I basically want to make backups of my web root directory and store 90 days worth.  I want to basically write a script to match the following

 

PLATFORM:

UBUNTU 9.04 RUNNING APACHE

 

run everyday..I assume this is a crontab function

 

 

backup directories are named "backup_".a        where a = 1-90

 

figure out how to get the last directory saved to

 

Since I do not want to override my backups if a server boot happens.

I supposed the last directory saved will have to be a check on the date?

 

get $a of last directory saved to

$a++

cp * /var/www /media/Elements/backup_$a

 

 

[trq]

Your probably much better of making what's known as an incremental backup. This saves spaces by only backing up data that has changed.

 

Its easily achieved using rsync instead of a plain old copy. If you google rsync incremental backup you should find plenty of example scripts around, its pretty common practice.

[Daniel0]

If you want to do a full backup you can do something simple like this. Just make it run daily using a cron job.

 

#!/bin/bash

BACKUP_DIR=/path/to/your/backups
SOURCE_DIR=/var/www

mkdir -p $BACKUP_DIR

TIMESTAMP=`date +%Y-%m-%d-%H%M`
tar cfj $SOURCE_DIR/backup_$TIMESTAMP.tar.bz2

find $BACKUP_DIR/* -mtime +7 -exec rm -rf {} \;

[drumhrd]

doesn't an incremental backup overwrite the changes?  which would be fine as long as I have 90 days worth...if I change a file everyday over 90 days..and the error was in the 28th one..I want to be able to go back and restore that file back to day 28.  I assumed incremental backups overwrite changes so I could not go back to day 28 and restore it from there..I could only restore the last day 89.

[Daniel0]

No.

[drumhrd]

ok so the content of my backup script is as follows

 

#!/bin/bash

BACKUP_DIR=/media/Elements
SOURCE_DIR=/var/www

mkdir -p $BACKUP_DIR

TIMESTAMP=`date +%Y-%m-%d-%H%M`
tar cfj $SOURCE_DIR/backup_$TIMESTAMP.tar.gz

find $BACKUP_DIR/* -mtime +7 -exec rm -rf {} \;

 

 

I chmod 777 and execute

 

I get

 

tar: Cowardly refusing to create an empty archive

Try `tar --help' or `tar --usage' for more information.

 

 

 

Any Ideas? 

[Daniel0]

Oh yeah sorry. Change

tar cfj $SOURCE_DIR/backup_$TIMESTAMP.tar.gz

to

tar cfj $BACKUP_DIR/backup_$TIMESTAMP.tar.gz $SOURCE_DIR

 

That script does not do incremental backups though.

[drumhrd]

well the script is working..but I cannot open the zip files

 

gunzip backup_2009-09-15-1516.tar.gz

 

gzip: backup_2009-09-15-1516.tar.gz: not in gzip format

 

 

I modified the tar command slightly to exclude a /test directory I have in /var/www

 

tar cfj $BACKUP_DIR/backup_$TIMESTAMP.tar.gz --exclude=test $SOURCE_DIR

 

[Daniel0]

Oops, sorry. They're in bzip2 format. Rename to *.tar.bz2 instead.

[drumhrd]

awesome worked like a charm..just got to cron it up and I'll be good to go.

 

thanks for the help