[Server-devel] Changing to symple rsync for XO laptop backup

[Jerry Van Baren]

Tony Pearson wrote:
> 
> Team,
> While the "rsnapshot" looks good for our Nepal school/firewall/backup 
> configuration, it assumes that both the client and server are 
> continuously running, which we know is not true for the XO laptops 
> themselves.
> 
> I am thinking of developing instead a script that performs a once-a-day 
> rsync to the schoolserver.  This would probably not be able to run at 
> startup, but rather a cron job that checks to see if the XO is connected 
> to the school server, and has not backed up today yet, and performs the 
> "rsync" at that time.
> 
> Let me know if anyone else is working on anything like this to avoid 
> re-inventing the wheel.
> 
> Thanks
> 
> 	
> 	*Tony Pearson*

Hi Tony,

I use rsnapshot on all my machines to usb-attached hard drives for my 
backup scheme.  Rsnapshot is GREAT!  For my laptops, I rsnapshot every 
two hours whether they are awake or sleeping.  When they are sleeping, I 
get a hard-link copy of the snapshot of two hours previous and no 
changes, which doesn't take much disk space.  When the laptops are 
awake, I get a new snapshot (hard link of unchanged files + newly 
changed files).  Since the laptops are usually awake for more than two 
hours a day, this grabs at least one effective backup per day.

I started down the path of pinging the laptop to determine if it was 
awake or sleeping before rsnapshotting it, but that was a bunch of 
unreliable monkeybusiness.  Then it occurred to me that it was MUCH 
simpler and more effective rsnapshot them regardless of whether the 
snapshot "worked" or not.  If it didn't "work", no harm was done.  If it 
did work, benefit was done.

I don't notice a performance hit when the rsnapshot is running on my 
laptops.  My primary laptop is a one year old core2duo.  My other laptop 
is a five year old Fujitsu Crusoe that is really slow - but I don't use 
that one a lot (wife & kids get the leftovers ;-) so rsnapshot might 
have more impact on it.

I'm not currently doing this with my OLPC... I don't know how much 
impact the disk/network activity would be.

Best regards,
gvb