On Fri, 1 Oct 1999, Yubyub Bird wrote:

>> -----Original Message-----
>> From: der Mouse [mailto:mouse@Rodents.Montreal.QC.CA]
>> Sent: Friday, October 01, 1999 2:09 AM
>> To: tech-kern@netbsd.org
>> Subject: SCSI network
>>
>>
>> I'm contemplating using SCSI interfaces as a networking medium.  Does
>> anyone have any thoughts on where I should look for (a) convincing a
>> machine that it should speak on other than ID 7
>
>And a second question: a year or two ago, I was working at a place where
>they had bunches of Sequent machines.  These machines could share disk packs
>connected only via scsi - no proprietary busses AFAIK.  Each machine was
>able to mount the same volume read/write.  What would be involved in doing
>this?  Is this just a filesystem feature, or is there a more complicated
>SCSI locking protocol which takes place?

Take a look at http://www.globalfilesystem.org, which is a filesystem
which can be shared between two (or more?) Linux hosts on the same SCSI
bus.  It uses SCSI-3 features to store metadata locks in the RAM in each
disk, and the locks time out (so the filesystem doesn't hang if the host
holding a lock suddenly goes away).  Although this is being developed
under Linux, they're talking about porting it to other systems (including
*BSD) once it's reasonably stable.


Roger

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Roger Brooks (Systems Programmer),          |  Email: R.S.Brooks@liv.ac.uk
Computing Services Dept,                    |  Tel:   +44 151 794 4441
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