2048kb block size

Danny Braniss danny at cs.huji.ac.il
Fri Oct 7 05:10:58 PDT 2005


> On Fri, Oct 07, 2005 at 13:08:05 +0300, Danny Braniss wrote:
> > hope this doesn't sound too silly, but can the scsi blcksize be set/changed?
> > i know that the 'disk' can be formated to any blocksize, the question
> > is does the CAM/da know about non 512 block size?
> 
> CDROM drives often have jumpers to go between 2048 byte and 512 byte
> blocks.
> 
ha, yes, the old suns could only handle 512!

> Some hard drives can be formatted for block sizes from 512 to 528 bytes.
> Anything larger than 512 in that case is used for per-sector ECC
> information and is typically only used by RAID controllers.
> 
> The da(4) driver uses read capacity to get the device size and blocksize,
> and should be able to handle most any blocksize.  (You might want to stick
> with powers of 2, although it would be interesting to see if anything in
> the stack breaks with a blocksize that isn't a power of 2.)
> 
this is a iSCSI target that was so configured and my driver stopped working,
so while im trying to debug it, i am shooting in the dark.

thanks,
	danny

> Ken
> -- 
> Kenneth Merry
> ken at FreeBSD.ORG




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