From owner-freebsd-fs  Mon Sep 17  5:13:28 2001
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Subject: Re: Porting a new filesystem to FreeBSD
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Date: Mon, 17 Sep 2001 13:17:10 +0100 (BST)
Cc: hch@ns.caldera.de (Christoph Hellwig),
	Dennis.Berger@nipsi.de (Dennis Berger), freebsd-fs@FreeBSD.ORG,
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In-Reply-To: <3BA5BDBC.107DC520@mindspring.com> from "Terry Lambert" at Sep 17, 2001 02:09:16 AM
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> This disagrees with a discussion I had off list, as to the use
> and availableility of DLOCK, and the firmness of the SCSI III
> standard.  The GFS people are using Matt Jacob's fiberchannel
> driver, and a network based distributed lock manager.

DLOCK is available on a suprisingly large number of FC drives, but
DLOCK is actually useless if you want any kind of fault tolerance - and
to an extent so is the very basis of GFS. 

> If someone would write a fiberchannle driver, and tell me where I
> can buy cheap hardware, I could probably write a GFS-like FS from
> scratch; but it's not something I'm interested in taking on, if it
> means that there's nothing to run it on but local disks, when I get
> there (ugh!).

The issue with hardware is mostly getting hold of a magic adapter.

QlogicFC 2100 controllers go or $US30 at times on ebay
FC drives go for peanuts because nobody knows what to do with them 2nd hand

But the magic "connect a single fc driver to fc" board you need to avoid
using expensive fc disk array boxes are like gold dust

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