Re: Bug#381150: still not able to handle partitionable arrays

Re: Bug#381150: still not able to handle partitionable arrays

[Robert Millan]

It seems there are problems with accessing software RAID in devices with
pathnames like /dev/md_d0p1

On Sat, Jan 06, 2007 at 05:59:16PM +0100, martin f krafft wrote:
> 
> grub2 1.95-2 still does not support partitionable arrays:
> 
> [...]
> 
> debian# grub-probe -v /boot
> grub-probe: info: changing current directory to /dev
> grub-probe: info: changing current directory to i2o
> grub-probe: info: changing current directory to ataraid
> grub-probe: info: changing current directory to shm
> grub-probe: info: changing current directory to network
> grub-probe: info: changing current directory to input
> grub-probe: info: changing current directory to cciss
> grub-probe: info: changing current directory to mapper
> grub-probe: info: changing current directory to ida
> grub-probe: info: changing current directory to rd
> grub-probe: info: changing current directory to pts
> cannot find a GRUB drive for md_d0p1.

-- 
Robert Millan

My spam trap is honeypot@aybabtu.com.  Note: this address is only intended
for spam harvesters.  Writing to it will get you added to my black list.

Re: Bug#381150: still not able to handle partitionable arrays

[Yoshinori K. Okuji]

On Saturday 05 May 2007 01:29, Robert Millan wrote:
> It seems there are problems with accessing software RAID in devices with
> pathnames like /dev/md_d0p1

Is there any specification about device names on Linux? I have been seeing 
Linux adding more and more new inconsistent device names for years, and it 
seems to be no end in this game.

Okuji

Re: Bug#381150: still not able to handle partitionable arrays

[Robert Millan]

On Mon, May 07, 2007 at 09:03:48PM +0200, Yoshinori K. Okuji wrote:
> On Saturday 05 May 2007 01:29, Robert Millan wrote:
> > It seems there are problems with accessing software RAID in devices with
> > pathnames like /dev/md_d0p1
> 
> Is there any specification about device names on Linux? I have been seeing 
> Linux adding more and more new inconsistent device names for years, and it 
> seems to be no end in this game.

Not that I know of.  But a few days ago I was toying with the idea that grub
could theoreticaly become device path agnostic.  Maybe this doesn't apply to
specific things like software RAID / LVM, but for most weird devices it's
probably feasible.

-- 
Robert Millan

My spam trap is honeypot@aybabtu.com.  Note: this address is only intended
for spam harvesters.  Writing to it will get you added to my black list.

Re: Bug#381150: still not able to handle partitionable arrays

[Jeroen Dekkers]

At Mon, 7 May 2007 22:00:50 +0200,
Robert Millan wrote:
> 
> On Mon, May 07, 2007 at 09:03:48PM +0200, Yoshinori K. Okuji wrote:
> > On Saturday 05 May 2007 01:29, Robert Millan wrote:
> > > It seems there are problems with accessing software RAID in devices with
> > > pathnames like /dev/md_d0p1
> > 
> > Is there any specification about device names on Linux? I have been seeing 
> > Linux adding more and more new inconsistent device names for years, and it 
> > seems to be no end in this game.

The best part is actually that it's not the only name, from the mdadm manpage:

"""
The standard names for non-partitioned arrays (the only sort of md array available in 2.4 and earlier) either of

              /dev/mdNN
              /dev/md/NN

where NN is a number.  The standard names for partitionable arrays (as available from 2.6 onwards) is one of

              /dev/md/dNN
              /dev/md_dNN

Partition numbers should be indicated by added "pMM" to these, thus "/dev/md/d1p2". 
"""

> Not that I know of.  But a few days ago I was toying with the idea that grub
> could theoreticaly become device path agnostic.  Maybe this doesn't apply to
> specific things like software RAID / LVM, but for most weird devices it's
> probably feasible.

I've been thinking about that too, because the current way seems a bit
fragile. But then you're looking up the device major and minor number
for partionable RAID arrays and you see that it's in the
"LOCAL/EXPERIMENTAL USE" range. Not very useful either...

Jeroen Dekkers

Re: Bug#381150: still not able to handle partitionable arrays

[Jeroen Dekkers]

At Sat, 5 May 2007 01:29:07 +0200,
Robert Millan wrote:
> It seems there are problems with accessing software RAID in devices with
> pathnames like /dev/md_d0p1
> 
> On Sat, Jan 06, 2007 at 05:59:16PM +0100, martin f krafft wrote:
> > 
> > grub2 1.95-2 still does not support partitionable arrays:
> > 
> > [...]
> > 
> > debian# grub-probe -v /boot
> > grub-probe: info: changing current directory to /dev
> > grub-probe: info: changing current directory to i2o
> > grub-probe: info: changing current directory to ataraid
> > grub-probe: info: changing current directory to shm
> > grub-probe: info: changing current directory to network
> > grub-probe: info: changing current directory to input
> > grub-probe: info: changing current directory to cciss
> > grub-probe: info: changing current directory to mapper
> > grub-probe: info: changing current directory to ida
> > grub-probe: info: changing current directory to rd
> > grub-probe: info: changing current directory to pts
> > cannot find a GRUB drive for md_d0p1.

My latest commit to GRUB2 CVS should fix this.

Jeroen Dekkers

Re: Bug#381150: still not able to handle partitionable arrays

[Robert Millan]

tags 381150 fixed-upstream
thanks

On Fri, May 18, 2007 at 01:28:15AM +0200, Jeroen Dekkers wrote:
> > > cannot find a GRUB drive for md_d0p1.
> 
> My latest commit to GRUB2 CVS should fix this.

Martin, can you check if things work for you before next upload ?

-- 
Robert Millan

My spam trap is honeypot@aybabtu.com.  Note: this address is only intended
for spam harvesters.  Writing to it will get you added to my black list.

Re: Bug#381150: still not able to handle partitionable arrays

[Michael Guntsche]

On May 18, 2007, at 1:28, Jeroen Dekkers wrote:

>
> My latest commit to GRUB2 CVS should fix this.
>
> Jeroen Dekkers

Hello,

This also seems to fix the detection for LVM devices. grub-probe -t 
{drive,device} works now, partmap on the other hand still fails.

<snip>
grub-probe: info: changing current directory to /dev/mapper
grub-probe: info: opening fatoftheland-main
grub-probe: error: Cannot detect partition map for fatoftheland-main

For now I install everything manually but maybe this can be fixed as  
well.

Kind regards,
Michael

Re: Bug#381150: still not able to handle partitionable arrays

[Jeroen Dekkers]

At Fri, 18 May 2007 09:34:53 +0200,
Michael Guntsche wrote:
> This also seems to fix the detection for LVM devices. grub-probe -t 
> {drive,device} works now, partmap on the other hand still fails.

That was actually a different fix that I committed on the 16th.
 
> <snip>
> grub-probe: info: changing current directory to /dev/mapper
> grub-probe: info: opening fatoftheland-main
> grub-probe: error: Cannot detect partition map for fatoftheland-main
> 
> For now I install everything manually but maybe this can be fixed as  
> well.

This is actually the same problem as with software RAID, currently
grub-probe doesn't have a way to get the underlying device and lookup
the partition map. Maybe I've time to look into this later today, but
I've first some other things to do.

Jeroen Dekkers

Re: Bug#381150: still not able to handle partitionable arrays

[Yoshinori K. Okuji]

On Thursday 17 May 2007 23:25, Jeroen Dekkers wrote:
> I've been thinking about that too, because the current way seems a bit
> fragile. But then you're looking up the device major and minor number
> for partionable RAID arrays and you see that it's in the
> "LOCAL/EXPERIMENTAL USE" range. Not very useful either...

Hmm...

Okuji