[X-Unix] using rsync to automatically backup home directories (was RE: rsync help)

[Eric F Crist]

Since a few people showed interest, I'll spam the list with my  
solution for incremental backups of the mac in my life.

The major problem I had was that most of the macs in my life are  
laptops.  That means two primary things:
1) They go to sleep when I do. ;)
2) They roam off-network.

Since I already have a server network setup at home (secure- 
computing.net), I simply made use of my current backup server's hard  
disk space, and rsync.

The first step was to create an easy backup script, that was clickable  
for a user to manually backup their files.  *side note, when I say  
user, I mean my beloved fiance ;)*

This script contained a single line:
rsync -av --delete ~/ --exclude="Caches" --exclude="*.cdr" -- 
exclude="*.iso" --exclude=".Trash" --exclude=".Spotlight-V100" -- 
exclude=".Trashes" backup-server:/usr/backups/`hostname`

All the user needed to do was click on the script and it would backup  
any changes to their files.

At this point, her hard drive crashed.  Easy enough, we had backups.   
Well, the original backups from my testing.  6 months before.  Damn.

So, we had the need to automate.  I tried iCal, but if the laptop was  
asleep for 3 days, it would try to backup three times, and we got an  
iCal alert for each day.  My solution was to use the oft-unused (on  
Macs) cron daemon.  I added the following entry to her crontab:

00	*	*	*	*	/Users/<username>/backup.command

This, coupled with the backup.command file I'll paste below, results  
in her laptop backing itself up every hour, incrementally.  This works  
great, as she's often (2-3 times a day, on average) using her laptop  
as the hour rolls over.  Since she mostly surfs the web and checks  
email, the backup actually takes about 60 seconds to 2 minutes.

As I have found, this script works great on my laptop as well, even  
though my system roams with me to Starbucks, the office, and  
elsewhere.  That being said, my backups take about 1 minute to 5  
minutes.  The big thing when remote from the backup server is to have  
the --exclude="Caches".  These, especially Safari, can get rather large.

On my system, I've coupled GeekTool (http://projects.tynsoe.org/en/geektool/ 
) to tail the log file from my backups, so I can keep track of them  
throughout the day.  Without going further into GeekTool, here's the  
script I've got for that:
<CONSOLE> echo "System Backup Log:"; tail -n 20 /Users/ecrist/.logs/ 
`date "+%m"`/`date "+%d-%H"`.log ; echo "\nUpdated at `date`."

So, here's my minimal backup.command script:

#!/bin/sh
month=`date "+%m"`
file=`date "+%d-%H"`
# dont run if it's already running!
if [ -e "/tmp/back.pid" ]
then
echo "Backups already running as PID `cat /tmp/back.pid`.  Aborting..."
else
echo $$ > /tmp/back.pid
## ALL ONE LINE BETWEEN ##
rsync -av --delete ~/ --exclude="Caches" --exclude="*.cdr" -- 
exclude="*.iso" --exclude=".Trash" --exclude=".Spotlight-V100" -- 
exclude=".Trashes" backup-server:/usr/backups/`hostname` > /Users/ 
ecrist/.logs/$month/$file.log 2>&1
## ALL ONE LINE BETWEEN ^^ ##
rm /tmp/back.pid
fi
echo "Finished at `date`" >> /Users/ecrist/.logs/$month/$file.log


One final note.  My backup server has a user account for everyone  
that's going to be backing up their system.  Their backup directory  
has 0700 permissions for security's sake.  Since we're backing up  
laptops mostly, the `hostname` part of the rsync command works fine.   
This could be clarified for multiuser systems by running the cron job  
as root on the Macs, or simply creating a new rsync command such as:

rsync -av --delete ~/ <excludes> backup-server:/usr/backups/`hostname`/ 
`whoami`

Just make sure in this case that their user belongs to a group that  
has rwx access to the `hostname` directory.

Glad I could contribute something!  If this is confusing or you need  
help, please don't hesitate to ask!
-----
Eric F Crist
Secure Computing Networks