I have a big question. I'm posting it at several reputable forums in hopes t
hat someone out there knows an answer. I work for a company that uses a numb
er of Dell Servers with PERC cards to handle our RAID configurations. Recent
ly I was assigned the task of setting up RAID 10's utilizing the PERC 3/DC, 
which is the main controller we use. I happened to stumble across some docum
entation on the Dell website which states that "On the PERC 2/SC, 2/DC, 3/SC
, 3/DCL, 3/DC, and 3/QC controllers, RAID-10 is implemented as RAID-1 Concat
enated." According to Dell's definition of Concatenation earlier in this sam
e article, "Data fills up the first disk before it is written to the second 
disk." In other words, in a true RAID 10 one gets redundancy because all dat
a is mirrored on two hard drives but one also gets data access optimization 
because the data has been striped across all the mirrors. In RAID 1C (as I h
ave dubbed it) you get redundancy because all data is mirrored but you lost 
the access optimization because the data is written to the first hard drive 
until it is finished, the it goes on to the second and so on. Not only is th
ere a data bottleneck as data is written, but also when it is accessed becau
se the data needed is not likely to be on multiple drives and thus all reque
sts focus (generally) on only one drive, creating a bottleneck.
	We intended to upgrade to a 4/DC to overcome this problem, however I wanted
 to "triple check" that the 4/DC supported true RAID 10 and the 3/DC (etc.) 
did not. I called DELL and after spending over an hour on the phone with the
m was told that they were unsure whether either the 3 or 4 series of PERC ca
rds supported true RAID 10.
	My question is, does anyone know? Does any PERC card support true RAID 10?
	Here is the Dell product page that states that the 3/DC supports RAID 10: http://
accessories.us.dell....k=&refurbished=
	Here is the Dell Documentation page that states that 3/DC does not support true RAID 1
0: http://support.ap.dell.com/docs/SOF...31/ch3_stor.htm
	Anyone who can clear up this question will be our hero.
David.

[ Post a follow-up to this message ]