> What is the best approach to handle incremental backup 
> data, if hard disks are not that reliable this days? 
> (This is a home system, and tape drives and variants are out!)

That depends on the size of your data.  
How big are we talking about?

For me, I use Subversion to keep full history of my 
development files on a remote server.  For the databases,
I pull daily backups using scp.  Then, at the end
of each week, I write the data backups and a copy
of all my working files to a DVD.

That works well for me.
	
> Which are the best marks of hard drives to purchase, 
> especially for linux-based systems that can be on for 
> relatively long periods -- 6-24 hours a day?

I use Seagate drives on all my servers.  They are running
Linux and are on 24x7.  Failures are very rare and Seagate
replaces anything that fails within 5 years with no
hassle.

I hope this helps,
	Neil
	
--
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