What's the Difference??

[owais]

Hey, can anyone explain to me the difference between Raid and regular Ide? Can someone also explain the different forms of SCSI?? Which one would be the best??
Thanks.

 

[Guest]

Ok, Ill have a crack at this, There are 3 different types of SCSI, scsi, scsi 2, and ultra wide scsi, the actual ultra wide scsi cable is narrower than the scsi 2 cable because its sorta woven, its actually very nice to look at, scsi cables have either 50 or 64 pins, they used to be all the rage but will probably be superseded within a couple of years.
There are 5 different levels of RAID, dont ask me what they all are because it would take all week to detail them, ide is actually the term used to describe the type of hdd, eg scsi or IDE, and I believe you can have a ide raid array.

Hope this helps

 

[LordKaos]

Sorry! But you´re missing the Ultra-SCSI 3, Ultra-wide 3, and the Ultra 160!

Just thought to bring a little kaos in to the subject! ;-)

Better burn in Hell with some company than freeze in Heaven all alone

 

[Guest]

>>Ultra-SCSI 3, Ultra-wide 3, and the Ultra 160!<<

SCSI standards don't differentiate themselves by narrow and wide. Each standard naturally incorporates both narrow and wide (except for SCSI where wide wasn't in use yet).

SCSI (narrow only)
SCSI-2 (both included from point on)
Ultra SCSI (doesn't incorporate all SCSI-3 standards even though some manufacturers still use SCSI-3 to label products)
SCSI-3
Ultra2 SCSI
U160 SCSI
U320 SCSI (I don't think this is really a defined standard yet as manufacturers are labeling their products U320, but they are not all the same)


***Hey I run Intel... but let's get real***

 

[Guest]

could be wrong but i think u320 is actually the standard adopted by the scsi commity (as well as u640). u160 is not. the standard of this type is actually ultra3, after ultra2. u160 i believe is a term that adaptec came up with. they took a set of features that were accepted for the standard of u3 and came up with a name for this set. the problem with u3 is that to be ultra3 compliant does not necessarily mean compatible with other ultra3 devices. Seems wierd for a "standard", so that's why adaptec and other companies came up with and adopted ultra160.

also there are 80 pin scsi drives that supply power as well as data. so that you can swap drives while the power is still on in case a drive goes bad and you a running a network or something you can't turn off the computer while you change drives.

 

[Guest]

Well it's very similar to SCSI-3 and Ultra deal. Ultra3 is a set of features supported but are not all adopted for every device and manufacturer. U160 is widely used subset of certain number of those features. But there are U160 subsets that incorporate all of those features of Ultra3, which is probably where the incompatabilities occur. Though some devices should be configurable to run with widely used U160 features, a few that won't (kinda the nature of SCSI).

The 80-pin interfaces are covered in SCSI-3 standards along with protocols such as Fibre Channel and Firewire.



***Hey I run Intel... but let's get real***

 

[Guest]

Yeah well, Its been a while since Ive made a scuzzy sys, and my hdd book is on loan to a friend, Dont hear anyone disagree with me that it will be outdated in a year or Two

 

[Guest]

The 80 pin connectors found on some of the SCSI drives are called SCA connectors (Single Connector Attachment) and carry all of the SCSI bus lines as well as power and SCSI ID and some drive configuration jumpers. They are used in Servers for the most part, RAID arrays because they are Hot Swappable in a RAID 5+1 configuration.

Mike

 

[Guest]

yes and the SCA-2 is defined in SCSI-3 ... And they are Hot Swappable period... certainly in any redundant RAID array

***Hey I run Intel... but let's get real***