RE: 2757 Controller Card

The redbook knows.  There's charts inside.

www.redbooks.ibm.com - search for System Builder

When you read that redbook, there's charts about specific disks which
answer some of your query - however, not sure where you'd find an
official "I/O per second sustained" number.  The more cache the better.
I'd recommend the 2780 with cache backup - if you lose that much cache
in a failure, you're basically guaranteed a reload.
---------

The #2757 PCI-X Ultra RAID Disk Controller is an Ultra SCSI disk unit
controller 
with a 757 MB compressed maximum cache that provides RAID-5 protection
for 
internal disk units. It also supports up to two internal tape devices,
CD-ROM, and 
DVD units. The #2757 has four Ultra SCSI buses.
The #2757 is not supported in the system unit of Models 520, 550, 570,
or 595. 
A minimum of three disk units of the same capacity is needed for a valid
RAID-5 
configuration. A maximum of six arrays is allowed per controller, with a
maximum 
of 18 disk units allowed per array.  

The #2780 PCI-X Ultra RAID Disk Controller is an Ultra4 (u320) SCSI disk
unit 
controller with a maximum compressed write cache of 757 MB and a maximum

compressed read cache of 1GB that provides RAID-5 protection for
internal disk 
units. It also supports up to two internal tape devices, CD-ROM, and DVD
units. 
The #2780 has four Ultra4 SCSI buses.
The #2780 is not supported in the system unit of the Model 520, 550,
570, or 
595. Up to 20 disk units per #2780 are supported in a #5094 PCI-X
Expansion 
Tower attached to a Model 520, 550, 570, or 595. 
A minimum of three disk units of the same capacity is needed for a valid
RAID-5 
configuration. A maximum of six arrays is allowed per controller, with a
maximum 
of 18 disk units allowed per array. 


--
Justin C. Haase - iSeries System Engineer
IBM Certified Systems Expert - System i
Kingland Systems Corporation

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Ryan Hunt
Sent: Tuesday, July 18, 2006 9:27 AM
To: midrange-l@xxxxxxxxxxxx
Subject: 2757 Controller Card

Anyone know how much data the 2757 Controller Card can handle?  Is it
U320?
More importantly, how many I/O's per second can it sustain?



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