FC5 RAID 1 - booting off either drive

[Laurence Vanek]

Greetings -

To my surprise, fresh install of FC5 with RAID 1 configured at install 
time went without a hitch.  I have /dev/md0 defined on /boot 
partitions.  It boots fine with this setup.

I had my FC4 system setup this exact way except I found that I had to 
manually install grub on one of the disks to permit booting off either 
one if the other is down.

Does anyone know of a way to check for the presence of grub on each 
drive (obviously its on hda since it boots presently) to see if this 
needs to be done for FC5 also without powering down each drive in turn & 
attempting to boot?

[Christofer C. Bell]

On 3/27/06, Laurence Vanek <lvanek(a)charter.net&gt; wrote:
>  Does anyone know of a way to check for the presence of grub on each
>  drive (obviously its on hda since it boots presently) to see if this
>  needs to be done for FC5 also without powering down each drive in turn &
>  attempting to boot? 
This is all I could come up with.  I'm sure there has to be another way.  heh

[root@circe ~]# dd if=/dev/hda bs=384 count=1 | strings
1+0 records in
1+0 records out
8,|     u
ZRrI
D|f1
GRUB
[root@circe ~]#

--
Chris

"I trust the Democrats to take away my money, which I can afford.  I
trust the Republicans to take away my freedom, which I cannot."

[Craig White]

On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
>  Greetings -
>  
>  To my surprise, fresh install of FC5 with RAID 1 configured at install 
>  time went without a hitch.  I have /dev/md0 defined on /boot 
>  partitions.  It boots fine with this setup.
>  
>  I had my FC4 system setup this exact way except I found that I had to 
>  manually install grub on one of the disks to permit booting off either 
>  one if the other is down.
>  
>  Does anyone know of a way to check for the presence of grub on each 
>  drive (obviously its on hda since it boots presently) to see if this 
>  needs to be done for FC5 also without powering down each drive in turn & 
>  attempting to boot? 
----
thought I should post against the right thread

just an untested thought...

bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1

diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin

Thinking...

- substitute different values for sda/sdb as fits
- the first 512 bytes on each drive are the boot (perhaps less, someone
will surely correct me...it might just be the first 256 or 384 bytes)
- if they are the same (i.e. grub has been installed on both), there
will be no diff

otherwise...

grub-install /dev/sdb

Of course, the only way that you'll ever KNOW for sure that it's going
to work is to do a real simulation, i.e. disconnecting one drive, then
the other drive...

Craig

[Craig White]

On Tue, 2006-03-28 at 08:05 -0700, Craig White wrote:
>  On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
>  > Greetings -
>  > 
>  > To my surprise, fresh install of FC5 with RAID 1 configured at install 
>  > time went without a hitch.  I have /dev/md0 defined on /boot 
>  > partitions.  It boots fine with this setup.
>  > 
>  > I had my FC4 system setup this exact way except I found that I had to 
>  > manually install grub on one of the disks to permit booting off either 
>  > one if the other is down.
>  > 
>  > Does anyone know of a way to check for the presence of grub on each 
>  > drive (obviously its on hda since it boots presently) to see if this 
>  > needs to be done for FC5 also without powering down each drive in turn & 
>  > attempting to boot?
>  ----
>  thought I should post against the right thread
>  
>  just an untested thought...
>  
>  bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
>  bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1
>  
>  diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin
>  
>  Thinking...
>  
>  - substitute different values for sda/sdb as fits
>  - the first 512 bytes on each drive are the boot (perhaps less, someone
>  will surely correct me...it might just be the first 256 or 384 bytes)
>  - if they are the same (i.e. grub has been installed on both), there
>  will be no diff
>  
>  otherwise...
>  
>  grub-install /dev/sdb
>  
>  Of course, the only way that you'll ever KNOW for sure that it's going
>  to work is to do a real simulation, i.e. disconnecting one drive, then
>  the other drive... 
----
not only wrong thread but as Paul so correctly points out.

dd - NOT bb

I am rapidly ingesting coffee but haven't figured out a mainline method
so I am left to normal ingestion methods which apparently haven't quite
caught up to my fingers or my brain.

duh.

Sorry

Craig

[Laurence Vanek]

Craig White wrote:
>  On Tue, 2006-03-28 at 08:05 -0700, Craig White wrote:
>    
> > On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
> >     
> >> Greetings -
> >>
> >> To my surprise, fresh install of FC5 with RAID 1 configured at install 
> >> time went without a hitch.  I have /dev/md0 defined on /boot 
> >> partitions.  It boots fine with this setup.
> >>
> >> I had my FC4 system setup this exact way except I found that I had to 
> >> manually install grub on one of the disks to permit booting off either 
> >> one if the other is down.
> >>
> >> Does anyone know of a way to check for the presence of grub on each 
> >> drive (obviously its on hda since it boots presently) to see if this 
> >> needs to be done for FC5 also without powering down each drive in turn & 
> >> attempting to boot?
> >>       
> > ----
> > thought I should post against the right thread
> >
> > just an untested thought...
> >
> > bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
> > bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1
> >
> > diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin
> >
> > Thinking...
> >
> > - substitute different values for sda/sdb as fits
> > - the first 512 bytes on each drive are the boot (perhaps less, someone
> > will surely correct me...it might just be the first 256 or 384 bytes)
> > - if they are the same (i.e. grub has been installed on both), there
> > will be no diff
> >
> > otherwise...
> >
> > grub-install /dev/sdb
> >
> > Of course, the only way that you'll ever KNOW for sure that it's going
> > to work is to do a real simulation, i.e. disconnecting one drive, then
> > the other drive...
> >     
>  ----
>  not only wrong thread but as Paul so correctly points out.
>
>  dd - NOT bb
>
>  I am rapidly ingesting coffee but haven't figured out a mainline method
>  so I am left to normal ingestion methods which apparently haven't quite
>  caught up to my fingers or my brain.
>
>  duh.
>
>  Sorry
>
>  Craig
>
>     
Followed your suggestion.  Boot sectors were NOT the same size on hda & 
hdc (hdd is my CD-RW).  Same deal as with FC4.  I installed grub on my 
second drive (hdc) using:

#grub
grub>root (hd1,0)
grub>setup (hd1)
grub>quit

powered down, unplugged hda & VIOLA! (it boots).

Thanks for the help.

[Craig White]

On Tue, 2006-03-28 at 20:20 -0600, Laurence Vanek wrote:
>  Craig White wrote:
>  > On Tue, 2006-03-28 at 08:05 -0700, Craig White wrote:
>  >   
>  >> On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
>  >>     
>  >>> Greetings -
>  >>>
>  >>> To my surprise, fresh install of FC5 with RAID 1 configured at install 
>  >>> time went without a hitch.  I have /dev/md0 defined on /boot 
>  >>> partitions.  It boots fine with this setup.
>  >>>
>  >>> I had my FC4 system setup this exact way except I found that I had to 
>  >>> manually install grub on one of the disks to permit booting off either 
>  >>> one if the other is down.
>  >>>
>  >>> Does anyone know of a way to check for the presence of grub on each 
>  >>> drive (obviously its on hda since it boots presently) to see if this 
>  >>> needs to be done for FC5 also without powering down each drive in turn &
>
>  >>> attempting to boot?
>  >>>       
>  >> ----
>  >> thought I should post against the right thread
>  >>
>  >> just an untested thought...
>  >>
>  >> bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
>  >> bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1
>  >>
>  >> diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin
>  >>
>  >> Thinking...
>  >>
>  >> - substitute different values for sda/sdb as fits
>  >> - the first 512 bytes on each drive are the boot (perhaps less, someone
>  >> will surely correct me...it might just be the first 256 or 384 bytes)
>  >> - if they are the same (i.e. grub has been installed on both), there
>  >> will be no diff
>  >>
>  >> otherwise...
>  >>
>  >> grub-install /dev/sdb
>  >>
>  >> Of course, the only way that you'll ever KNOW for sure that it's going
>  >> to work is to do a real simulation, i.e. disconnecting one drive, then
>  >> the other drive...
>  >>     
>  > ----
>  > not only wrong thread but as Paul so correctly points out.
>  >
>  > dd - NOT bb
>  >
>  > I am rapidly ingesting coffee but haven't figured out a mainline method
>  > so I am left to normal ingestion methods which apparently haven't quite
>  > caught up to my fingers or my brain.
>  >
>  > duh.
>  >
>  > Sorry
>  >
>  > Craig
>  >
>  >   
>  Followed your suggestion.  Boot sectors were NOT the same size on hda & 
>  hdc (hdd is my CD-RW).  Same deal as with FC4.  I installed grub on my 
>  second drive (hdc) using:
>  
>  #grub
>  grub>root (hd1,0)
>  grub>setup (hd1)
>  grub>quit
>  
>  powered down, unplugged hda & VIOLA! (it boots).
>  
>  Thanks for the help. 
----
sure thing - just wondering (for completeness and all) - in case anyone
looks at the archives...

if you do...

dd if=/dev/hda of=/tmp/hda-512.bin bs=512 count=1
dd if=/dev/hdc of=/tmp/hdc-512.bin bs=512 count=1
diff /tmp/hda-512.bin /tmp/hdc-512.bin

do they match? (ie...diff comes up empty?)

How about as Aaron suggested...466 bytes...

dd if=/dev/hda of=/tmp/hda-466.bin bs=466 count=1
dd if=/dev/hdc of=/tmp/hdc-466.bin bs=466 count=1
diff /tmp/hda-466.bin /tmp/hdc-466.bin

do they match?

I can see a lot of occasions where the partition tables might not match
on the hard drives (such as Dell's utility partition being on /dev/hda
but not /dev/hdc or different brand drives, etc.)...

Craig

[Laurence Vanek]

Craig White wrote:
>  On Tue, 2006-03-28 at 08:05 -0700, Craig White wrote:
>    
> > On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
> >     
> >> Greetings -
> >>
> >> To my surprise, fresh install of FC5 with RAID 1 configured at install 
> >> time went without a hitch.  I have /dev/md0 defined on /boot 
> >> partitions.  It boots fine with this setup.
> >>
> >> I had my FC4 system setup this exact way except I found that I had to 
> >> manually install grub on one of the disks to permit booting off either 
> >> one if the other is down.
> >>
> >> Does anyone know of a way to check for the presence of grub on each 
> >> drive (obviously its on hda since it boots presently) to see if this 
> >> needs to be done for FC5 also without powering down each drive in turn & 
> >> attempting to boot?
> >>       
> > ----
> > thought I should post against the right thread
> >
> > just an untested thought...
> >
> > bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
> > bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1
> >
> > diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin
> >
> > Thinking...
> >
> > - substitute different values for sda/sdb as fits
> > - the first 512 bytes on each drive are the boot (perhaps less, someone
> > will surely correct me...it might just be the first 256 or 384 bytes)
> > - if they are the same (i.e. grub has been installed on both), there
> > will be no diff
> >
> > otherwise...
> >
> > grub-install /dev/sdb
> >
> > Of course, the only way that you'll ever KNOW for sure that it's going
> > to work is to do a real simulation, i.e. disconnecting one drive, then
> > the other drive...
> >     
>  ----
>  not only wrong thread but as Paul so correctly points out.
>
>  dd - NOT bb
>
>  I am rapidly ingesting coffee but haven't figured out a mainline method
>  so I am left to normal ingestion methods which apparently haven't quite
>  caught up to my fingers or my brain.
>
>  duh.
>
>  Sorry
>
>  Craig
>
>     
Craig -

my present drive condition is:

=========
[root@localhost tmp]# dd if=/dev/hda of=/tmp/hda-bootblock.bin bs=512 
count=1
1+0 records in
1+0 records out
512 bytes (512 B) copied, 8e-05 seconds, 6.4 MB/s
[root@localhost tmp]# dd if=/dev/hdc of=/tmp/hdc-bootblock.bin bs=512 
count=1
1+0 records in
1+0 records out
512 bytes (512 B) copied, 7.2e-05 seconds, 7.1 MB/s
[root@localhost tmp]# diff hda-bootblock.bin hdc-bootblock.bin Binary 
files hda-bootblock.bin and hdc-bootblock.bin differ
=============

although diff says they are different, I can boot off either with the 
other unplugged.  I guess the dd, diff method is not definitive.

[Craig White]

On Wed, 2006-03-29 at 18:39 -0600, Laurence Vanek wrote:
>  Craig White wrote:
>  > On Tue, 2006-03-28 at 08:05 -0700, Craig White wrote:
>  >   
>  >> On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
>  >>     
>  >>> Greetings -
>  >>>
>  >>> To my surprise, fresh install of FC5 with RAID 1 configured at install 
>  >>> time went without a hitch.  I have /dev/md0 defined on /boot 
>  >>> partitions.  It boots fine with this setup.
>  >>>
>  >>> I had my FC4 system setup this exact way except I found that I had to 
>  >>> manually install grub on one of the disks to permit booting off either 
>  >>> one if the other is down.
>  >>>
>  >>> Does anyone know of a way to check for the presence of grub on each 
>  >>> drive (obviously its on hda since it boots presently) to see if this 
>  >>> needs to be done for FC5 also without powering down each drive in turn &
>
>  >>> attempting to boot?
>  >>>       
>  >> ----
>  >> thought I should post against the right thread
>  >>
>  >> just an untested thought...
>  >>
>  >> bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
>  >> bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1
>  >>
>  >> diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin
>  >>
>  >> Thinking...
>  >>
>  >> - substitute different values for sda/sdb as fits
>  >> - the first 512 bytes on each drive are the boot (perhaps less, someone
>  >> will surely correct me...it might just be the first 256 or 384 bytes)
>  >> - if they are the same (i.e. grub has been installed on both), there
>  >> will be no diff
>  >>
>  >> otherwise...
>  >>
>  >> grub-install /dev/sdb
>  >>
>  >> Of course, the only way that you'll ever KNOW for sure that it's going
>  >> to work is to do a real simulation, i.e. disconnecting one drive, then
>  >> the other drive...
>  >>     
>  > ----
>  > not only wrong thread but as Paul so correctly points out.
>  >
>  > dd - NOT bb
>  >
>  > I am rapidly ingesting coffee but haven't figured out a mainline method
>  > so I am left to normal ingestion methods which apparently haven't quite
>  > caught up to my fingers or my brain.
>  >
>  > duh.
>  >
>  > Sorry
>  >
>  > Craig
>  >
>  >   
>  Craig -
>  
>  my present drive condition is:
>  
>  =========
>  [root@localhost tmp]# dd if=/dev/hda of=/tmp/hda-bootblock.bin bs=512 
>  count=1
>  1+0 records in
>  1+0 records out
>  512 bytes (512 B) copied, 8e-05 seconds, 6.4 MB/s
>  [root@localhost tmp]# dd if=/dev/hdc of=/tmp/hdc-bootblock.bin bs=512 
>  count=1
>  1+0 records in
>  1+0 records out
>  512 bytes (512 B) copied, 7.2e-05 seconds, 7.1 MB/s
>  [root@localhost tmp]# diff hda-bootblock.bin hdc-bootblock.bin Binary 
>  files hda-bootblock.bin and hdc-bootblock.bin differ
>  =============
>  
>  although diff says they are different, I can boot off either with the 
>  other unplugged.  I guess the dd, diff method is not definitive. 
----
I think we expected that - but the first 466 bytes should not be any
different - which is why I wanted you to try that too.

Craig

[Laurence Vanek]

Craig White wrote:
>  On Tue, 2006-03-28 at 08:05 -0700, Craig White wrote:
>    
> > On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
> >     
> >> Greetings -
> >>
> >> To my surprise, fresh install of FC5 with RAID 1 configured at install 
> >> time went without a hitch.  I have /dev/md0 defined on /boot 
> >> partitions.  It boots fine with this setup.
> >>
> >> I had my FC4 system setup this exact way except I found that I had to 
> >> manually install grub on one of the disks to permit booting off either 
> >> one if the other is down.
> >>
> >> Does anyone know of a way to check for the presence of grub on each 
> >> drive (obviously its on hda since it boots presently) to see if this 
> >> needs to be done for FC5 also without powering down each drive in turn & 
> >> attempting to boot?
> >>       
> > ----
> > thought I should post against the right thread
> >
> > just an untested thought...
> >
> > bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
> > bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1
> >
> > diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin
> >
> > Thinking...
> >
> > - substitute different values for sda/sdb as fits
> > - the first 512 bytes on each drive are the boot (perhaps less, someone
> > will surely correct me...it might just be the first 256 or 384 bytes)
> > - if they are the same (i.e. grub has been installed on both), there
> > will be no diff
> >
> > otherwise...
> >
> > grub-install /dev/sdb
> >
> > Of course, the only way that you'll ever KNOW for sure that it's going
> > to work is to do a real simulation, i.e. disconnecting one drive, then
> > the other drive...
> >     
>  ----
>  not only wrong thread but as Paul so correctly points out.
>
>  dd - NOT bb
>
>  I am rapidly ingesting coffee but haven't figured out a mainline method
>  so I am left to normal ingestion methods which apparently haven't quite
>  caught up to my fingers or my brain.
>
>  duh.
>
>  Sorry
>
>  Craig
>
>     
Craig -

results using bs=466
============
[root@localhost tmp]# dd if=/dev/hda of=/tmp/hda-bootblock.bin bs=466 
count=1
1+0 records in
1+0 records out
466 bytes (466 B) copied, 7.6e-05 seconds, 6.1 MB/s
[root@localhost tmp]# dd if=/dev/hdc of=/tmp/hdc-bootblock.bin bs=466 
count=1
1+0 records in
1+0 records out
466 bytes (466 B) copied, 7.7e-05 seconds, 6.1 MB/s
[root@localhost tmp]# diff hda-bootblock.bin hdc-bootblock.bin
Binary files hda-bootblock.bin and hdc-bootblock.bin differ
================

files also differ is bs=256, 128
BUT for bs=64 we get no complaint from diff:

================
[root@localhost tmp]# dd if=/dev/hda of=/tmp/hda-bootblock.bin bs=64 count=1
1+0 records in
1+0 records out
64 bytes (64 B) copied, 7.8e-05 seconds, 821 kB/s
[root@localhost tmp]# dd if=/dev/hdc of=/tmp/hdc-bootblock.bin bs=64 count=1
1+0 records in
1+0 records out
64 bytes (64 B) copied, 7.6e-05 seconds, 842 kB/s
[root@localhost tmp]# diff hda-bootblock.bin hdc-bootblock.bin
================

[Craig White]

On Fri, 2006-03-31 at 23:34 -0600, Laurence Vanek wrote:
>  Craig White wrote:
>  > On Tue, 2006-03-28 at 08:05 -0700, Craig White wrote:
>  >   
>  >> On Mon, 2006-03-27 at 21:43 -0600, Laurence Vanek wrote:
>  >>     
>  >>> Greetings -
>  >>>
>  >>> To my surprise, fresh install of FC5 with RAID 1 configured at install 
>  >>> time went without a hitch.  I have /dev/md0 defined on /boot 
>  >>> partitions.  It boots fine with this setup.
>  >>>
>  >>> I had my FC4 system setup this exact way except I found that I had to 
>  >>> manually install grub on one of the disks to permit booting off either 
>  >>> one if the other is down.
>  >>>
>  >>> Does anyone know of a way to check for the presence of grub on each 
>  >>> drive (obviously its on hda since it boots presently) to see if this 
>  >>> needs to be done for FC5 also without powering down each drive in turn &
>
>  >>> attempting to boot?
>  >>>       
>  >> ----
>  >> thought I should post against the right thread
>  >>
>  >> just an untested thought...
>  >>
>  >> bb if=/dev/sda of=/tmp/sda-bootblock.bin bs=512 count=1
>  >> bb if=/dev/sdb of=/tmp/sdb-bootblock.bin bs=512 count=1
>  >>
>  >> diff /tmp/sda-bootblock.bin /tmp/sdb-bootblock.bin
>  >>
>  >> Thinking...
>  >>
>  >> - substitute different values for sda/sdb as fits
>  >> - the first 512 bytes on each drive are the boot (perhaps less, someone
>  >> will surely correct me...it might just be the first 256 or 384 bytes)
>  >> - if they are the same (i.e. grub has been installed on both), there
>  >> will be no diff
>  >>
>  >> otherwise...
>  >>
>  >> grub-install /dev/sdb
>  >>
>  >> Of course, the only way that you'll ever KNOW for sure that it's going
>  >> to work is to do a real simulation, i.e. disconnecting one drive, then
>  >> the other drive...
>  >>     
>  > ----
>  > not only wrong thread but as Paul so correctly points out.
>  >
>  > dd - NOT bb
>  >
>  > I am rapidly ingesting coffee but haven't figured out a mainline method
>  > so I am left to normal ingestion methods which apparently haven't quite
>  > caught up to my fingers or my brain.
>  >
>  > duh.
>  >
>  > Sorry
>  >
>  > Craig
>  >
>  >   
>  Craig -
>  
>  results using bs=466
>  ============
>  [root@localhost tmp]# dd if=/dev/hda of=/tmp/hda-bootblock.bin bs=466 
>  count=1
>  1+0 records in
>  1+0 records out
>  466 bytes (466 B) copied, 7.6e-05 seconds, 6.1 MB/s
>  [root@localhost tmp]# dd if=/dev/hdc of=/tmp/hdc-bootblock.bin bs=466 
>  count=1
>  1+0 records in
>  1+0 records out
>  466 bytes (466 B) copied, 7.7e-05 seconds, 6.1 MB/s
>  [root@localhost tmp]# diff hda-bootblock.bin hdc-bootblock.bin
>  Binary files hda-bootblock.bin and hdc-bootblock.bin differ
>  ================
>  
>  files also differ is bs=256, 128
>  BUT for bs=64 we get no complaint from diff:
>  
>  ================
>  [root@localhost tmp]# dd if=/dev/hda of=/tmp/hda-bootblock.bin bs=64 count=1
>  1+0 records in
>  1+0 records out
>  64 bytes (64 B) copied, 7.8e-05 seconds, 821 kB/s
>  [root@localhost tmp]# dd if=/dev/hdc of=/tmp/hdc-bootblock.bin bs=64 count=1
>  1+0 records in
>  1+0 records out
>  64 bytes (64 B) copied, 7.6e-05 seconds, 842 kB/s
>  [root@localhost tmp]# diff hda-bootblock.bin hdc-bootblock.bin
>  ================ 
----
well - you sort of blew my theory right out of the water - thanks.

the theory being, that the grub boot blocks on both drives should be the
same - I guess that something is different on both drives but in theory,
I was thinking that if it were installed...

grub-install /dev/hda
grub-install /dev/hdc

then they should both be the same boot blocks. On yours, the boot blocks
on /dev/hda were written by the installer (anaconda) and on /dev/hdc
were written by you manually by issuing 'grub' command and stepping
through it manually as I recall.

;-(

Well, I'm glad it worked...sorry I was really of little help.

Craig

[Laurence Vanek]

Craig -

It has not been a waste of time.  I learned a few things - thanks.

Your suggestion would still be valid if the boot block size is bs=64.  I 
also did not check for sizes between 64 & 128.