Hi,

ProtecTier on work over FC protocol but I have never heard that it require
FC disk... When I meet with diligent people from Israel, I told them that we
already have 7 TB of SATA that we which to "re-use", that would be no
problem, they said.

They only support FC arrays today, but in that array you can have both FC
and SATA drives. It feels strange creating a backup-to-disk solution that
only support FC disks...

The guy selling you ProtecTier, does he work at HDS and want you to buy a
solution that includes expensive FC disks?? ;-)

I think you need to find another source to Diligent, or perhaps I need to
find one that tells me the truth.. :-)





Hampus Lind
Rikspolisstyrelsen
National Police Board
Tel dir: +46 (0)8 - 401 99 43
Tel mob: +46 (0)70 - 217 92 66
E-mail: hampus.lind at rps.police.se


-----Ursprungligt meddelande-----
Fr?n: Paul Keating [mailto:pkeating at bank-banque-canada.ca] 
Skickat: den 15 september 2006 14:51
Till: Hampus Lind; briandiven at northwesternmutual.com;
didier.brun at fr.thalesgroup.com
Kopia: veritas-bu at mailman.eng.auburn.edu
?mne: RE: [Veritas-bu] problems with VTL StorageTek solution ?

I like the look of the ProtecTIER product.

However, I've come up with some information that I can't get a hard
answer on.
The info I got from Diligent coonfused me even more.

Everything I can find, and am told by either HDS, or Diligent says that
Protectier requires FC disk.......as in, not SATA......

I find this confusing.....sure the data de-duplication technology
requires knowing where the data is on disk, quickly, etc, etc. So I said
to the Diligent rep I spoke with "Ok, so the de-duplication algorithm
actually has to search the disk to find patterns?" to which I got the
response (paraphrasing)"Oh no, of course not...all of the data on disk
is mapped in RAM, we can map 1PB of disk in 4GB of RAM. The appliance
doesn't need to read the disk to find hash matches, etc. All of that is
done in RAM and only the unique data that needs to be written to disk is
written to disk".
So I asked why then would FC disk be necessary???
After pushing it a bit, I got a response that Yes, it would technically
"work" with SATA disk, however there would be a performance hit due to
SATA's transfer speed, of approx 40%, so they don't support SATA.

So....here's my confusion....since the de-duplication is being done "in
stream" on the appliance before the data ever gets to the disk array,
then with the advertised 25:1 ratio, only 4% of the data hitting the box
is getting written to disk.

Even if the SATA disk is 80% slower that FC (being fascetious here),
shouldn't it still be like 5 times faster than another product that
writes "everything" to SATA disk? Yes all the other VTL vendors are
basing their products on SATA (as Diligent is with their VTF Open
product)


Paul

-- 


> -----Original Message-----
> From: veritas-bu-bounces at mailman.eng.auburn.edu 
> [mailto:veritas-bu-bounces at mailman.eng.auburn.edu] On Behalf 
> Of Hampus Lind
> Sent: September 14, 2006 1:54 PM
> To: briandiven at northwesternmutual.com; didier.brun at fr.thalesgroup.com
> Cc: veritas-bu at mailman.eng.auburn.edu
> Subject: Re: [Veritas-bu] problems with VTL StorageTek solution ?
> 
> 
> However, I have looked at both diligent and falconstor, and 
> for now I think
> I would go with diligent.. What do you guys think?? 
>