SAS Backplane and Controller Card Questions

IceDigger

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Lets say I have this setup

4u supermicro server w/ sas6 controller and unknown backplane. 12gb sas 10tb drive

The 12gb sas drive will not register in the computer.

Is this an issue with the backplane being older or the sas controller being older or both?

I know nothing about sas backplanes.
 

Dan_D

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If the controller is slower, the drive will downgrade in speed. However, the back plane could be an issue. Back planes are a bit of a pain. It could be bad, or it just might not be cooperating due to the fact it may not have been designed for 12Gb/s drives. In theory, it should allow the negotiation at a slower speed, but this doesn't always work in my experience.
 

David_Schroth

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First gen SAS does not support drives over 2TB. Can you crack the case and get the part number off the backplane? Shouldn't be too hard to do....

You should be able to connect the drive straight to the board and yield profit.
 

Zarathustra

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Yeah, if you suspect a backplane issue, try bypassing it by connecting it straight to the controller.
 

Dan_D

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Yeah, if you suspect a backplane issue, try bypassing it by connecting it straight to the controller.
Indeed. Back planes suck and is the likely culprit. Eliminate or confirm it's the issue by bypassing it.
 

{NG}Fidel

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Indeed. Back planes suck and is the likely culprit. Eliminate or confirm it's the issue by bypassing it.
At my old DC jobs I would rather replace a mobo than a backplane half the time. The effort required was absurd.
 
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Early sas is size limited, my Dell r710 with perc 6i had a firmware update to be able to support 4TB drives... Probably a similar limitation. Either update was controller or plug large drive into sata port on MB and use smaller drives on sas/raid.
 
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