Date: Mon, 26 Oct 1998 11:09:35 -0600 From: peter@taronga.com (Peter da Silva) To: scsi@FreeBSD.ORG Subject: Re: Do we support > 32 drives yet? Message-ID: <199810261709.LAA29710@bonkers.taronga.com> In-Reply-To: <199810252349.QAA08774@panzer.plutotech.com> References: <199810251825.MAA04658@aurora.sol.net>
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>/* > 3 2 1 0 > 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 > _________________________________________________________________ > | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | > ----------------------------------------------------------------- > | TYPE |UNIT_2 | SLICE | MAJOR? | UNIT |PART | > ----------------------------------------------------------------- >*/ Other than hardcoding device numbers in the config file, is there any way of tying a device to a particular bus/target/lun combination the way you can in Digital UNIX and in System-V derived systems where this data is encoded into the minor number? This seems to be a requirement if you want to be able to hot-add drives. For example, I can plug a drive into a Storageworks shelf on my DU box, and calculate the minor number for it from the bus, target, and LUN (bus*K1+target*K2+lun)... on FreeBSD I'd have to prebuild a kernel or preallocate a bunch of unused minors. With an HSZ50 I can stick 12 shelves of drives on a single controller, for 84 drives per controller. We run these in JBOD mode because each project wants to be able to keep a couple of disks "on the shelf" if necessary, ready to slot in so they can get to work on a problem on a few minutes notice. Digital UNIX has a terrific SCSI subsystem, but it looks like FreeBSD is dogging its heels. This is one of the things keeping DU ahead. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message
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