Mylex DAC vs RAM disk in 2.4.2 devfs

Mylex DAC vs RAM disk in 2.4.2 devfs

[Russell Coker]

I have just upgraded a machine with a Mylex DAC hardware RAID controller to 
kernel 2.4.2 with devfs.

It seems that /dev/rd is used by both the RAM disk in the kernel and the 
Mylex controller!

This is wrong of course, there are two problems, one is the situation of what 
happens if you need both Mylex RAID and a RAM disk.  The other is the problem 
that Mylex devices get treated as ram disks by devfsd which cause an upgrade 
to break (the compatibility sym-links are not created correctly).
I believe that the RAM disk should be changed as /dev/rd has been used by 
Mylex controllers for a long time.  I am willing to submit patches to the 
kernel and to devfsd if this suggestion is accepted and someone can suggest a 
good directory name for ram-disks (I don't want to have the same problem 
again).

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Re: Mylex DAC vs RAM disk in 2.4.2 devfs

[Andreas Ferber]

Hi,

On Tue, Apr 17, 2001 at 01:22:01PM +0200, Russell Coker wrote:

> Mylex controllers for a long time.  I am willing to submit patches to the 
> kernel and to devfsd if this suggestion is accepted and someone can suggest a 
> good directory name for ram-disks (I don't want to have the same problem 
> again).

What about simply "ramdisk"? ;-)

Andreas
-- 
"How do you pronounce SunOS?"  "Just like you hear it, with a big SOS"
	-- dedicated to Roland Kaltefleiter

Re: Mylex DAC vs RAM disk in 2.4.2 devfs

[H. Peter Anvin]

Followup to:  <20010417140859.E4385@kallisto.sind-doof.de>
By author:    Andreas Ferber <aferber@techfak.uni-bielefeld.de>
In newsgroup: linux.dev.kernel
>
> Hi,
> 
> On Tue, Apr 17, 2001 at 01:22:01PM +0200, Russell Coker wrote:
> 
> > Mylex controllers for a long time.  I am willing to submit patches to the 
> > kernel and to devfsd if this suggestion is accepted and someone can suggest a 
> > good directory name for ram-disks (I don't want to have the same problem 
> > again).
> 
> What about simply "ramdisk"? ;-)
> 

The standard name is /dev/ramX.  If you want it directorized I suggest
/dev/ram/X.

	-hpa
-- 
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"Unix gives you enough rope to shoot yourself in the foot."
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Re: Mylex DAC vs RAM disk in 2.4.2 devfs

[Richard Gooch]

Russell Coker writes:
> I have just upgraded a machine with a Mylex DAC hardware RAID controller to 
> kernel 2.4.2 with devfs.
> 
> It seems that /dev/rd is used by both the RAM disk in the kernel and the 
> Mylex controller!
> 
> This is wrong of course, there are two problems, one is the situation of what 
> happens if you need both Mylex RAID and a RAM disk.  The other is the problem 
> that Mylex devices get treated as ram disks by devfsd which cause an upgrade 
> to break (the compatibility sym-links are not created correctly).
> I believe that the RAM disk should be changed as /dev/rd has been used by 
> Mylex controllers for a long time.  I am willing to submit patches to the 
> kernel and to devfsd if this suggestion is accepted and someone can suggest a 
> good directory name for ram-disks (I don't want to have the same problem 
> again).

Leonard and I are discussing the issue. We started at the kernel
summit, but didn't have time to continue. I've sent him an email.

				Regards,

					Richard....
Permanent: rgooch@atnf.csiro.au
Current:   rgooch@ras.ucalgary.ca