Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 23 Jan 1999 04:17:39 +0100
From:      "Karsten W. Rohrbach" <rohrbach@nacamar.net>
To:        freebsd-hackers@FreeBSD.ORG
Subject:   Re: SCSI question... and some enum idea
Message-ID:  <19990123041739.G4581@nacamar.net>
In-Reply-To: <Pine.BSF.4.05.9812241139490.618-100000@m4.stox.sa.enteract.com>; from Kenneth P. Stox on Thu, Dec 24, 1998 at 11:48:21AM -0600
References:  <19981224102230.T365@acheron.middleboro.ma.us> <Pine.BSF.4.05.9812241139490.618-100000@m4.stox.sa.enteract.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Kenneth P. Stox (ken@stox.sa.enteract.com) @ Thu, Dec 24, 1998 at 11:48:21AM -0600:
> 
> > 1) Our box is a multi-LUN SCSI device. Are multiple LUNs supported in FreeBSD
> > by default? (A complication is that I don't know what version of FreeBSD our
> > client runs. I've been told -current, but I doubt that. I'm guessing 2.0.x.
> > I will find out for sure on Monday, but getting a jump over the weekend would
> > be cool.)
> 
> I can't speak on 2.X, but 3.X supports them just fine. I should note that
> my experience with multiple LUN's has been limited to a CD drive.
>

i got a box with 2940u2w(aic789x) and raid array on an infortrend ift3102
running here. the ift does create multiple luns for the different logical
disks - and it works excellent for me. 

btw, what came to my mind in this context was the enumeration of disk
devices (da?)... on some $$$ un*x boxes you got a scheme where the device
inode enumeration is fixed to the bus, scsi id and lun of the device
(pretty good idea that) so that if you sometimes add or remove your second
disk the third doesnt get the second and gets a mount error with wrong
filesystem type... so you would use /dev/disk/bus0id0lun0a or something as
root device... is this a good idea or is it rather nasty? i am often
swapping in/out our cd toaster of my department which is jumpered to id4
and i'm a lazy bastard, so my drive on id5 and the cdrom on id6 change
device numbers sometimes...

/k
 
> > 
> > 2) Can I access multiple LUNs through individual device files? If so, can I
> > assume that the kernel will pop up messages saying what files have devices
> > attached?
> 
> Yes. I have been using a 7 CD changer for some time with no problems.
> They come up as cd0 through cd6. I have used with with both Adaptec and
> NCR controllers.
> 
> > 3) Should I have the client do "/dev/MAKEDEV all" before rebooting with the
> > device attached? That would do what I want under NetBSD, but I'm not quite
> > sure about FreeBSD.
> 
> Since, you don't mention what kind of multiple LUN device you are talking
> about, that is hard to answer. :-)
> 
> 
> 
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-hackers" in the body of the message

-- 
"Nuclear war can ruin your whole compile." -- Karl Lehenbauer
http://www.nacamar.de - http://www.nacamar.net - http://www.webmonster.de 
http://www.apache.de - http://www.quakeforum.de - finger rohrbach@nacamar.net
PGP Key fingerprint = F9 A0 DF 91 74 07 6A 1C  5F 0B E0 6B 4D CD 8C 44

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?19990123041739.G4581>