Using xfsdump On Linux With IRIX Version 1 FS?

Using xfsdump On Linux With IRIX Version 1 FS?

[Sean Elble]

Hi all,

While I am aware that the current kernel implementation of XFS doesn't
support mounting an IRIX filesystem with version 1 directories, I'm not so
sure whether xfsdump/xfsrestore will support the dumping of an IRIX
filesystem with version 1 directories.  To be more specific, I am dealing
with an old disk from an Indigo2, running IRIX 6.5.6m with version 1
(0x1094) directories.  I was hoping it had version 2 directories, but after
finding an old SCSI card I could put in a Linux box with XFS support, I
found just the opposite, obviously.  I had the old SCSI card back in its
donor system (which was up-and-running) when it occurred to me that
xfsdump/xfsrestore *might* be a possibility, and I can't take it (the donor
system) down again unless I know I can make this work.

If anyone can give me an answer to this question, I would certainly
appreciate it.  I didn't see anything in the man pages, and my Google
searches have proven fruitless thus far, but I've been known to be blind on
occasion.  :-)  Thanks, in advance.

-- 
+-------------------------------------------------
|  Sean Elble      
|  Virginia Tech, Class of 2009
|  E-Mail:   elbles@sessys.com
|  Web:      http://www.sessys.com/~elbles/
|  Cell:     860.946.9477
+-------------------------------------------------



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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Eric Sandeen]

Sean Elble wrote:
> Hi all,
> 
> While I am aware that the current kernel implementation of XFS doesn't
> support mounting an IRIX filesystem with version 1 directories, I'm not so
> sure whether xfsdump/xfsrestore will support the dumping of an IRIX
> filesystem with version 1 directories.  To be more specific, I am dealing
> with an old disk from an Indigo2, running IRIX 6.5.6m with version 1
> (0x1094) directories.  I was hoping it had version 2 directories, but after
> finding an old SCSI card I could put in a Linux box with XFS support, I
> found just the opposite, obviously.  I had the old SCSI card back in its
> donor system (which was up-and-running) when it occurred to me that
> xfsdump/xfsrestore *might* be a possibility, and I can't take it (the donor
> system) down again unless I know I can make this work.
> 
> If anyone can give me an answer to this question, I would certainly
> appreciate it.  I didn't see anything in the man pages, and my Google
> searches have proven fruitless thus far, but I've been known to be blind on
> occasion.  :-)  Thanks, in advance.
> 

linux used to work with v1 dirs, though there were some problems.  It
never got fixed, was not critical for 99.9% of users, and got taken out.
 But it might work well enough to do what you need.  Go through the
changelogs or google, and try an older Linux kernel, perhaps ....

-Eric

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Sean Elble]

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On 7/23/09 10:23 PM, "Eric Sandeen" <sandeen@sandeen.net> wrote:

> Sean Elble wrote:
>> Hi all,
>> 
>> While I am aware that the current kernel implementation of XFS doesn't
>> support mounting an IRIX filesystem with version 1 directories, I'm not so
>> sure whether xfsdump/xfsrestore will support the dumping of an IRIX
>> filesystem with version 1 directories.  To be more specific, I am dealing
>> with an old disk from an Indigo2, running IRIX 6.5.6m with version 1
>> (0x1094) directories.  I was hoping it had version 2 directories, but after
>> finding an old SCSI card I could put in a Linux box with XFS support, I
>> found just the opposite, obviously.  I had the old SCSI card back in its
>> donor system (which was up-and-running) when it occurred to me that
>> xfsdump/xfsrestore *might* be a possibility, and I can't take it (the donor
>> system) down again unless I know I can make this work.
>> 
>> If anyone can give me an answer to this question, I would certainly
>> appreciate it.  I didn't see anything in the man pages, and my Google
>> searches have proven fruitless thus far, but I've been known to be blind on
>> occasion.  :-)  Thanks, in advance.
>> 
> 
> linux used to work with v1 dirs, though there were some problems.  It
> never got fixed, was not critical for 99.9% of users, and got taken out.
>  But it might work well enough to do what you need.  Go through the
> changelogs or google, and try an older Linux kernel, perhaps ....
> 
> -Eric
> 

Thanks for the reply, Eric, I appreciate it.  I'll take a look and see what
I can find, being sure to post back the latest version of the kernel with
version 1 support.  Think it was removed during the 2.5.x period, or could
it possibly have made it to the 2.6 era?

-Sean

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Sean Elble]

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On 7/23/09 10:23 PM, "Eric Sandeen" <sandeen@sandeen.net> wrote:

> Sean Elble wrote:
>> Hi all,
>> 
>> While I am aware that the current kernel implementation of XFS doesn't
>> support mounting an IRIX filesystem with version 1 directories, I'm not so
>> sure whether xfsdump/xfsrestore will support the dumping of an IRIX
>> filesystem with version 1 directories.  To be more specific, I am dealing
>> with an old disk from an Indigo2, running IRIX 6.5.6m with version 1
>> (0x1094) directories.  I was hoping it had version 2 directories, but after
>> finding an old SCSI card I could put in a Linux box with XFS support, I
>> found just the opposite, obviously.  I had the old SCSI card back in its
>> donor system (which was up-and-running) when it occurred to me that
>> xfsdump/xfsrestore *might* be a possibility, and I can't take it (the donor
>> system) down again unless I know I can make this work.
>> 
>> If anyone can give me an answer to this question, I would certainly
>> appreciate it.  I didn't see anything in the man pages, and my Google
>> searches have proven fruitless thus far, but I've been known to be blind on
>> occasion.  :-)  Thanks, in advance.
>> 
> 
> linux used to work with v1 dirs, though there were some problems.  It
> never got fixed, was not critical for 99.9% of users, and got taken out.
>  But it might work well enough to do what you need.  Go through the
> changelogs or google, and try an older Linux kernel, perhaps ....
> 
> -Eric
> 

Looks like the version 1 directory code was removed as of June 15th, 2006,
per this:

http://oss.sgi.com/archives/xfs/2006-06/msg00067.html

But another post <http://oss.sgi.com/archives/xfs/2003-07/msg00495.html> has
a 2.4.21 kernel being used with a patch, so I'm not sure if I want to try a
2.6 kernel, or see if I can patch together a 2.4.x kernel on an old FC4 box
I have laying around.  Truth be told, it's a lot of work just to blank the
entries in /etc/shadow so I can login to a 150 MHz box again, so who knows
if I'll even try at this point, hah.

In any event, thanks a lot for the pointers in the right direction.

-Sean

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Matthias Schniedermeyer]

On 23.07.2009 23:32, Sean Elble wrote:
> On 7/23/09 10:23 PM, "Eric Sandeen" <sandeen@sandeen.net> wrote:
> 
> > Sean Elble wrote:
> >> Hi all,
> >> 
> >> While I am aware that the current kernel implementation of XFS doesn't
> >> support mounting an IRIX filesystem with version 1 directories, I'm not so
> >> sure whether xfsdump/xfsrestore will support the dumping of an IRIX
> >> filesystem with version 1 directories.  To be more specific, I am dealing
> >> with an old disk from an Indigo2, running IRIX 6.5.6m with version 1
> >> (0x1094) directories.  I was hoping it had version 2 directories, but after
> >> finding an old SCSI card I could put in a Linux box with XFS support, I
> >> found just the opposite, obviously.  I had the old SCSI card back in its
> >> donor system (which was up-and-running) when it occurred to me that
> >> xfsdump/xfsrestore *might* be a possibility, and I can't take it (the donor
> >> system) down again unless I know I can make this work.
> >> 
> >> If anyone can give me an answer to this question, I would certainly
> >> appreciate it.  I didn't see anything in the man pages, and my Google
> >> searches have proven fruitless thus far, but I've been known to be blind on
> >> occasion.  :-)  Thanks, in advance.
> >> 
> > 
> > linux used to work with v1 dirs, though there were some problems.  It
> > never got fixed, was not critical for 99.9% of users, and got taken out.
> >  But it might work well enough to do what you need.  Go through the
> > changelogs or google, and try an older Linux kernel, perhaps ....
> > 
> > -Eric
> > 
> 
> Looks like the version 1 directory code was removed as of June 15th, 2006,
> per this:
> 
> http://oss.sgi.com/archives/xfs/2006-06/msg00067.html
> 
> But another post <http://oss.sgi.com/archives/xfs/2003-07/msg00495.html> has
> a 2.4.21 kernel being used with a patch, so I'm not sure if I want to try a
> 2.6 kernel, or see if I can patch together a 2.4.x kernel on an old FC4 box
> I have laying around.  Truth be told, it's a lot of work just to blank the
> entries in /etc/shadow so I can login to a 150 MHz box again, so who knows
> if I'll even try at this point, hah.
> 
> In any event, thanks a lot for the pointers in the right direction.

I'd guess the disc isn't very big.

You just dd it completly (for backup).

Then search for the content of the shadow-file and blank out the entry 
with a hex-editor. Make sure that you don't change the filesize, pad 
the previous/following entry with any character you have to remove.






Bis denn

-- 
Real Programmers consider "what you see is what you get" to be just as 
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated, 
cryptic, powerful, unforgiving, dangerous.

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Andi Kleen]

Sean Elble <elbles@sessys.com> writes:
>
> But another post <http://oss.sgi.com/archives/xfs/2003-07/msg00495.html> has
> a 2.4.21 kernel being used with a patch, so I'm not sure if I want to try a
> 2.6 kernel, or see if I can patch together a 2.4.x kernel on an old FC4 box
> I have laying around.  Truth be told, it's a lot of work just to blank the
> entries in /etc/shadow so I can login to a 150 MHz box again, so who knows
> if I'll even try at this point, hah.

If you just want to modify /etc/shadow I would just search for the strings
on the raw disk and then edit them directly with some hex editor.
You'll need to fill in something with the same length, presumably
another encrypted password. Just make sure you generate it with 
the same algorithm as Irix.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only.

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Sean Elble]

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On 7/24/09 3:30 AM, "Matthias Schniedermeyer" <ms@citd.de> wrote:

>> 
>> Looks like the version 1 directory code was removed as of June 15th, 2006,
>> per this:
>> 
>> http://oss.sgi.com/archives/xfs/2006-06/msg00067.html
>> 
>> But another post <http://oss.sgi.com/archives/xfs/2003-07/msg00495.html> has
>> a 2.4.21 kernel being used with a patch, so I'm not sure if I want to try a
>> 2.6 kernel, or see if I can patch together a 2.4.x kernel on an old FC4 box
>> I have laying around.  Truth be told, it's a lot of work just to blank the
>> entries in /etc/shadow so I can login to a 150 MHz box again, so who knows
>> if I'll even try at this point, hah.
>> 
>> In any event, thanks a lot for the pointers in the right direction.
> 
> I'd guess the disc isn't very big.
> 
> You just dd it completly (for backup).
> 
> Then search for the content of the shadow-file and blank out the entry
> with a hex-editor. Make sure that you don't change the filesize, pad
> the previous/following entry with any character you have to remove.

Right, the disk is only 2 GB.  Presumably, to back the disk up, all I'd have
to do would be something like:

    dd if=/dev/sda of=IRIXbackup

Correct?  No need to specify bs or count, I presume...

Then, I could use hexedit in the following manner to edit the disk:

    hexedit -d -f /dev/sda

I suppose I could search for the encrypted password string itself, but as
Chris Wedgwood suggested, I might be better off finding the offset of the
/etc/shadow file by doing something like the following:
    
    xfs_ncheck /dev/sda | grep /etc/shadow

I'm not sure if I can use the inode number directly as an offset or not, but
I *think* I could use it in conjunction with a xfs_db convert command to get
something usable as an offset.  Something like the following, perhaps?

    xfs_db -c convert inode <inode from xfs_ncheck command> daddr /dev/sda

My apologies for all the questions, but I've never tried this before, and I
don't particularly feel like messing it up, even with a backup of the FS
available.  Many thanks to Andi Kleen and Chris Wedgwood, in addition to
Eric Sandeen and Matthias Schniedermeyer.

-Sean

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Matthias Schniedermeyer]

On 24.07.2009 11:36, Sean Elble wrote:
> On 7/24/09 3:30 AM, "Matthias Schniedermeyer" <ms@citd.de> wrote:
> 
> >> 
> >> Looks like the version 1 directory code was removed as of June 15th, 2006,
> >> per this:
> >> 
> >> http://oss.sgi.com/archives/xfs/2006-06/msg00067.html
> >> 
> >> But another post <http://oss.sgi.com/archives/xfs/2003-07/msg00495.html> has
> >> a 2.4.21 kernel being used with a patch, so I'm not sure if I want to try a
> >> 2.6 kernel, or see if I can patch together a 2.4.x kernel on an old FC4 box
> >> I have laying around.  Truth be told, it's a lot of work just to blank the
> >> entries in /etc/shadow so I can login to a 150 MHz box again, so who knows
> >> if I'll even try at this point, hah.
> >> 
> >> In any event, thanks a lot for the pointers in the right direction.
> > 
> > I'd guess the disc isn't very big.
> > 
> > You just dd it completly (for backup).
> > 
> > Then search for the content of the shadow-file and blank out the entry
> > with a hex-editor. Make sure that you don't change the filesize, pad
> > the previous/following entry with any character you have to remove.
> 
> Right, the disk is only 2 GB.  Presumably, to back the disk up, all I'd have
> to do would be something like:
> 
>     dd if=/dev/sda of=IRIXbackup
> 
> Correct?  No need to specify bs or count, I presume...

Exactly.

> Then, I could use hexedit in the following manner to edit the disk:
> 
>     hexedit -d -f /dev/sda

Don't know hexedit. Last time i used a hex editor it was "khexedit", 
worked good enough.

> I suppose I could search for the encrypted password string itself, but as
> Chris Wedgwood suggested, I might be better off finding the offset of the
> /etc/shadow file by doing something like the following:
>     
>     xfs_ncheck /dev/sda | grep /etc/shadow
> 
> I'm not sure if I can use the inode number directly as an offset or not, but
> I *think* I could use it in conjunction with a xfs_db convert command to get
> something usable as an offset.  Something like the following, perhaps?
> 
>     xfs_db -c convert inode <inode from xfs_ncheck command> daddr /dev/sda

2GB is small enough to just use "brute force".

- Make a backup-copy of the image
- Open the image in a/the hexeditor
- Search for something that appears in the shadow file
  it should be pretty obvious if the hit is inside the shadow file.
- Make the changes, (Remember filesize has to stay the same!) 
- dd the image back to the HDD.

Not very complicated and it still shouldn't take too long. :-)



Bis denn

-- 
Real Programmers consider "what you see is what you get" to be just as 
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated, 
cryptic, powerful, unforgiving, dangerous.

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Sean Elble]

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On 7/24/09 1:11 PM, "Matthias Schniedermeyer" <ms@citd.de> wrote:

> On 24.07.2009 11:36, Sean Elble wrote:
>> On 7/24/09 3:30 AM, "Matthias Schniedermeyer" <ms@citd.de> wrote:
>> 
>>> 
>>> I'd guess the disc isn't very big.
>>> 
>>> You just dd it completly (for backup).
>>> 
>>> Then search for the content of the shadow-file and blank out the entry
>>> with a hex-editor. Make sure that you don't change the filesize, pad
>>> the previous/following entry with any character you have to remove.
>> 
>> Right, the disk is only 2 GB.  Presumably, to back the disk up, all I'd have
>> to do would be something like:
>> 
>>     dd if=/dev/sda of=IRIXbackup
>> 
>> Correct?  No need to specify bs or count, I presume...
> 
> Exactly.
> 
>> Then, I could use hexedit in the following manner to edit the disk:
>> 
>>     hexedit -d -f /dev/sda
> 
> Don't know hexedit. Last time i used a hex editor it was "khexedit",
> worked good enough.
> 
>> I suppose I could search for the encrypted password string itself, but as
>> Chris Wedgwood suggested, I might be better off finding the offset of the
>> /etc/shadow file by doing something like the following:
>>     
>>     xfs_ncheck /dev/sda | grep /etc/shadow
>> 
>> I'm not sure if I can use the inode number directly as an offset or not, but
>> I *think* I could use it in conjunction with a xfs_db convert command to get
>> something usable as an offset.  Something like the following, perhaps?
>> 
>>     xfs_db -c convert inode <inode from xfs_ncheck command> daddr /dev/sda
> 
> 2GB is small enough to just use "brute force".
> 
> - Make a backup-copy of the image
> - Open the image in a/the hexeditor
> - Search for something that appears in the shadow file
>   it should be pretty obvious if the hit is inside the shadow file.
> - Make the changes, (Remember filesize has to stay the same!)
> - dd the image back to the HDD.
> 
> Not very complicated and it still shouldn't take too long. :-)
> 

Yeah, that's probably what I'll do then.  I figure the disk will thrash for
a while during the search for a string in /etc/shadow, but hopefully it'll
work.  Thanks for all the advice!

-Sean

-- 
+-------------------------------------------------
|  Sean Elble      
|  Virginia Tech, Class of 2009
|  E-Mail:   elbles@sessys.com
|  Web:      http://www.sessys.com/~elbles/
|  Cell:     860.946.9477
+-------------------------------------------------

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Christian Kujau]

On Fri, 24 Jul 2009 at 15:13, Sean Elble wrote:
> Yeah, that's probably what I'll do then.  I figure the disk will thrash for
> a while during the search for a string in /etc/shadow, but hopefully it'll

Instead of working on the (old, slow) disk, you could just work on the 
backup (located on faster disk, I presume), maybe even set up a 
blockdevice for it:

  # losetup -r /dev/loop0 /path/to/IRIXbackup
  # hexedit /dev/loop0 ...or whatever tool you'll be using.

Christian.
-- 
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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Matthias Schniedermeyer]

On 24.07.2009 20:53, Christian Kujau wrote:
> On Fri, 24 Jul 2009 at 15:13, Sean Elble wrote:
> > Yeah, that's probably what I'll do then.  I figure the disk will thrash for
> > a while during the search for a string in /etc/shadow, but hopefully it'll
> 
> Instead of working on the (old, slow) disk, you could just work on the 
> backup (located on faster disk, I presume), maybe even set up a 
> blockdevice for it:
> 
>   # losetup -r /dev/loop0 /path/to/IRIXbackup
>   # hexedit /dev/loop0 ...or whatever tool you'll be using.

Which has what advantage over directly changing the image?

And the old disc may be slow, but the relative speed (Speed in relation 
to total capacity) is much better than modern discs. IOW it only takes 
minutes to read/write it completly.

Some month ago i backed up some old HDDs (biggest was 4GB), it nearly 
took longer to switch on/off the computer and change the HDDs, than the 
actual time to copy the HDDs.
Even with just 10MB/s it's less than 4 Minutes for 2GB.
In comparison it takes over 3 hours to copy a modern 1TB HDD @ 80MB/s.






Bis denn

-- 
Real Programmers consider "what you see is what you get" to be just as 
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated, 
cryptic, powerful, unforgiving, dangerous.

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Christian Kujau]

On Sat, 25 Jul 2009 at 09:26, Matthias Schniedermeyer wrote:
> >   # losetup -r /dev/loop0 /path/to/IRIXbackup
> >   # hexedit /dev/loop0 ...or whatever tool you'll be using.
> 
> Which has what advantage over directly changing the image?

Sean mentioned the "thrashing of the old disk" and I figured I'd be 
worried not only by that but that the old disk might die anytime soon. So 
I wanted to present an alternative to do the search - I don't know too 
much about his setup, so it's up to him to follow this advice or not.

> Even with just 10MB/s it's less than 4 Minutes for 2GB.
> In comparison it takes over 3 hours to copy a modern 1TB HDD @ 80MB/s.

?? (what kind of comparison is that?)

C.
-- 
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Zombie processes detected, machine is haunted.

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Matthias Schniedermeyer]

On 25.07.2009 02:46, Christian Kujau wrote:
> On Sat, 25 Jul 2009 at 09:26, Matthias Schniedermeyer wrote:
> > >   # losetup -r /dev/loop0 /path/to/IRIXbackup
> > >   # hexedit /dev/loop0 ...or whatever tool you'll be using.
> > 
> > Which has what advantage over directly changing the image?
> 
> Sean mentioned the "thrashing of the old disk" and I figured I'd be 
> worried not only by that but that the old disk might die anytime soon. So 
> I wanted to present an alternative to do the search - I don't know too 
> much about his setup, so it's up to him to follow this advice or not.

I meant: What is the advantage of using the a loop-device (of the image) 
instead of directly using the image?

> > Even with just 10MB/s it's less than 4 Minutes for 2GB.
> > In comparison it takes over 3 hours to copy a modern 1TB HDD @ 80MB/s.
> 
> ?? (what kind of comparison is that?)

That you can read/write whole "ancient" discs without having to wait for 
hours?





Bis denn

-- 
Real Programmers consider "what you see is what you get" to be just as 
bad a concept in Text Editors as it is in women. No, the Real Programmer
wants a "you asked for it, you got it" text editor -- complicated, 
cryptic, powerful, unforgiving, dangerous.

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Christian Kujau]

On Sat, 25 Jul 2009 at 12:22, Matthias Schniedermeyer wrote:
> I meant: What is the advantage of using the a loop-device (of the image) 
> instead of directly using the image?

Some tools don't like to act on flat files, i.e. mkfs.reiserfs won't 
create a filesystem on a file without -forcing it, dunno about all the 
xfsprogs though, or "hexedit", or....

-- 
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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Sean Elble]

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On 7/25/09 5:46 AM, "Christian Kujau" <lists@nerdbynature.de> wrote:

> On Sat, 25 Jul 2009 at 09:26, Matthias Schniedermeyer wrote:
>>>   # losetup -r /dev/loop0 /path/to/IRIXbackup
>>>   # hexedit /dev/loop0 ...or whatever tool you'll be using.
>> 
>> Which has what advantage over directly changing the image?
> 
> Sean mentioned the "thrashing of the old disk" and I figured I'd be
> worried not only by that but that the old disk might die anytime soon. So
> I wanted to present an alternative to do the search - I don't know too
> much about his setup, so it's up to him to follow this advice or not.
> 
>

I think (and hope, considering its age) that the disk is OK.  My concern was
more with the speed that hexedit could traverse the drive searching for a
string, as opposed to dd'ing the drive to disk, editing the image, and then
dd'ing the image back to disk.

Using the loopback driver is definitely a thought, but I don't know if the
kernel on my spare box supports it or not.  I'll definitely take it into
consideration, depending on how it goes, so thanks for the info.

>> Even with just 10MB/s it's less than 4 Minutes for 2GB.
>> In comparison it takes over 3 hours to copy a modern 1TB HDD @ 80MB/s.
> 
> ?? (what kind of comparison is that?)
> 
> C.

-- 
+-------------------------------------------------
|  Sean Elble      
|  Virginia Tech, Class of 2009
|  E-Mail:   elbles@sessys.com
|  Web:      http://www.sessys.com/~elbles/
|  Cell:     860.946.9477
+-------------------------------------------------

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Re: Using xfsdump On Linux With IRIX Version 1 FS?

[Sean Elble]

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On 7/25/09 5:46 AM, "Christian Kujau" <lists@nerdbynature.de> wrote:

> On Sat, 25 Jul 2009 at 09:26, Matthias Schniedermeyer wrote:
>>>   # losetup -r /dev/loop0 /path/to/IRIXbackup
>>>   # hexedit /dev/loop0 ...or whatever tool you'll be using.
>> 
>> Which has what advantage over directly changing the image?
> 
> Sean mentioned the "thrashing of the old disk" and I figured I'd be
> worried not only by that but that the old disk might die anytime soon. So
> I wanted to present an alternative to do the search - I don't know too
> much about his setup, so it's up to him to follow this advice or not.
> 

Well, I ended up dd'ing the old SCSI disk to a file on a spare Linux box I
have laying around for just this sort of purpose.  I then opened the
resulting file up with hexedit, switched to ASCII mode, did a search for the
root password hash, and replaced it with a known hash for "blah."

DD'ed the image back to the disk, threw it back in the Indigo2, and booted.
I entered maintenace mode, ran sash, and cat'ed the /etc/shadow file.  It
still had the old password.  So, back to the image file I went.  The
password string was in there multiple times, to the point where I lost
count.  I should have thought of that the first time around, but I figured
once was good enough.  Searched and replaced the string until the old string
wasn't in there anymore, reimaged the drive, put it back in the SGI, booted,
and voila:  I can log in again.

The loopback method was a moot point, as the box I was using didn't have the
loopback driver compiled in or available as a module, so I never even tried
it.  I'll definitely keep it in mind (and in my inbox) should another few
years go by and I can't remember the password again. :-)

Thanks so much for all the help guys, I really appreciate it.

-Sean

-- 
+-------------------------------------------------
|  Sean Elble      
|  Virginia Tech, Class of 2009
|  E-Mail:   elbles@sessys.com
|  Web:      http://www.sessys.com/~elbles/
|  Cell:     860.946.9477
+-------------------------------------------------

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