Re: [tlug] Raid5 box & backup

[Curt Sampson <cjs@example.com>]

On 2008-05-27 12:35 +0900 (Tue), Bruno wrote:

> As I will use TeraStations, I am not tore to have a lot of choices.

Why are you so keen on using the TeraStations, rather than just regular
ol' computers, which would probably be cheaper as well.

Actually, looking at the product page, though, I see that Buffalo does
sell an iSCSI version of the Terrastation. And thinking about it, it
wouldn't be too hard to write a program that would sit on a host between
the iSCSI devices and the clients, watch every block go by, and log
the block numbers for replication to another iSCSI device somewhere
else. To grab missed blocks, you could also run a background process
that, over time, compared all of the blocks between the two systems
and updated anything that needed updating. This would be a pretty much
optimal replication scheme in terms of speed and bandwith, though a
bit dangerous if you don't have a filesystem quite resistant to losing
updates. I'd say the daemon should pay special attention to metadata
blocks, but with a crypto fs, of course, you don't know which ones they
are.

cjs
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Curt Sampson       <cjs@example.com>        +81 90 7737 2974   
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