F8 installation in external usb disk (not USB key)

[Miguel Blanco]

Hello!

Excuse me if this is a known FAQ, but I can't find any thing related
to external usb disk
(not USB key, ie. real 2.5" disk) but this
http://www.vigla.eclipse.co.uk/usb_install.pdf
paper wich refers to an old Fedora Core 3 version.

I tried the process described above translating where applicable to F8
with no sucess.

Do you know whow can I install F8 in an external disk ?

Regards,
Miguel

[Miguel Blanco]

Yes, you are rigth about the standard install and the BIOS drives remaps!

I tried configuring GRUB in the MBR of the external disk, and the procedure
described in the refered paper failed at the last point, ie. the kernel output
a lot of errors and failed to boot...

Thanks for your comments!

Regards,
Miguel.

2007/12/31, Mikkel L. Ellertson <mikkel(a)infinity-ltd.com&gt;:
>  Miguel Blanco wrote:
>  > Hello!
>  >
>  > Excuse me if this is a known FAQ, but I can't find any thing related
>  > to external usb disk
>  > (not USB key, ie. real 2.5" disk) but this
>  > http://www.vigla.eclipse.co.uk/usb_install.pdf
>  > paper wich refers to an old Fedora Core 3 version.
>  >
>  > I tried the process described above translating where applicable to F8
>  > with no sucess.
>  >
>  > Do you know whow can I install F8 in an external disk ?
>  >
>  > Regards,
>  > Miguel
>  >
>  You have to use the expert install. The standard install does not
>  offer to let you use USB drives. The drive will be accessed as a
>  SCSI drive. (Almost all drives in F8 are accessed as SCSI drives.)
>  Depending on your system, it will probably be /dev/sdb.
>
>  About the only complication is that you want to install Grub to the
>  USB drive. If you are planning on using the BIOS boot from a USB
>  device option, you will also have to modify the Grub device map so
>  that the USB drive is the first BIOS drive. (The BIOS remaps the
>  drives when you boot from the USB drive.) This is not necessary if
>  you are chainloading from another Grub install.
>
>  Mikkel
>  --
>
>    Do not meddle in the affairs of dragons,
>  for thou art crunchy and taste good with Ketchup!
>
>
>  --
>  fedora-list mailing list
>  fedora-list(a)redhat.com
>  To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>
>

[Miguel Blanco]

Thanks a lot,  John and Mikkel !!

As soon I can, I'll try again and I'll keep you updated.

Regards,
Miguel

2007/12/31, John Austin <ja(a)jaa.org.uk&gt;:
>  On Mon, 2007-12-31 at 17:00 +0100, Miguel Blanco wrote:
>  > Ok, I'll try again this time writing down all the steps and repost
>  > with the exact error. But I'll check, as you propose, the devices
>  > in /etc/fstab and /boot/grub/grub.conf
>  >
>  > Thank you!
>  >
>  > Regards,
>  > Miguel
>  >
>  > 2007/12/31, Mikkel L. Ellertson <mikkel(a)infinity-ltd.com&gt;:
>  > > Miguel Blanco wrote:
>  > > > Yes, you are rigth about the standard install and the BIOS drives remaps!
>  > > >
>  > > > I tried configuring GRUB in the MBR of the external disk, and the
> procedure
>  > > > described in the refered paper failed at the last point, ie. the kernel
> output
>  > > > a lot of errors and failed to boot...
>  > > >
>  > > > Thanks for your comments!
>  > > >
>  > > > Regards,
>  > > > Miguel.
>  > > >
>  > > If you get to the point where the kernel loads, and produces errors,
>  > > then the problem is ether in /etc/fstab or in /boot/grub/grub.conf.
>  > > Without knowing the errors, it is hard to tell. It probably is a
>  > > problem with the root device passed to the kernel from Grub. If you
>  > > are not using LVM, then the root device is probably something like
>  > > /dev/sdb5 and needs to be changed to /dev/sda5. (The 5 may not be
>  > > correct.) You may need to do the same thing in /etc/fstab. The
>  > > reason for this is that the usb_storage module is loaded from
>  > > initrd, so it becomes the first SCSI controller.
>  > >
>  > > A better way to handle it is to give all the partitions on the USB
>  > > drive labels, and use the labels instead of the device names. That
>  > > way, it does not matter what drive letter is assigned to the drive.
>  > >
>  > > Mikkel
>  > > --
>  > >
>  > >   Do not meddle in the affairs of dragons,
>  > > for thou art crunchy and taste good with Ketchup!
>  > >
>  > >
>  > > --
>  > > fedora-list mailing list
>  > > fedora-list(a)redhat.com
>  > > To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>  > >
>  > >
>  >
>  Hi Miguel
>
>  As  Mikkel has stated F8 will install to an external USB by just using
>  expert mode.
>  95% of the reference is unnecessary now.
>
>  I tend not to use LVM but I do pre-partition, pre-format and pre-label
>  the disk BEFORE starting
>  the install and the DO NOT format the disk during installation. (which
>  deletes the labels !)
>
>  The only real decisions are to do with how to boot.
>
>  If the USB disk is to rely on the MBR of a main SATA/IDE type disk then
>  choose the /dev/sdxy device associated with the USB disk at install
>  time.
>  Then add an entry to grub.conf on the fixed disk.
>  title USB disk
>          root (hdp,q)
>          chainloader +1
>
>  In addition after install I would then configure grub on the MBR of the
>  USB disk as well such that I can boot the disk with and without the
>  presence of the "main", "fixed" disk.
>
>  I did the whole of this on an external USB disk yesterday !!!!
>
>  After first having learnt how to use jigdo to down load
>  Fedora-Unity-20071218-8-i386-DVD.iso !!!!!!!!
>
>  As stated by Mikkel I had to play with grub interactively to sort out
>  the correct (hdx,y) !!
>
>  John
>
>  who wrote
>  http://www.vigla.eclipse.co.uk/usb_install.pdf
>
>
>
>
>
>
>  --
>  fedora-list mailing list
>  fedora-list(a)redhat.com
>  To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>

[Dr J Austin]

On Mon, 2007-12-31 at 12:33 -0600, Mikkel L. Ellertson wrote:
>  John Austin wrote:
>  > 
>  > The only real decisions are to do with how to boot.
>  > 
>  > If the USB disk is to rely on the MBR of a main SATA/IDE type disk then
>  > choose the /dev/sdxy device associated with the USB disk at install
>  > time.
>  > Then add an entry to grub.conf on the fixed disk.
>  > title USB disk
>  > 	root (hdp,q)
>  > 	chainloader +1
>  > 
>  > In addition after install I would then configure grub on the MBR of the
>  > USB disk as well such that I can boot the disk with and without the
>  > presence of the "main", "fixed" disk.
>  > 
>  What I did was install a copy of Grub to the MBR of the USB drive,
>  and then create an entry like this in the SATA Grub menu:
>  
>  title USB disk
>        root (hd0)
>        map (hd0) (hd1)
>        map (hd1) (hd0)
>        chainload +1
>  
>  Because of the map commands, the USB drive is hd0 when the chainload
>  command is executed, and it loads Grub from the USB drive. (hd0 is
>  the entire disk, starting from the MBR.) From there it is the same
>  as if you had used the BIOS option to boot from the USB drive. The
>  only thing you have to be careful of is if you have more then one
>  USB drive plugged in. You will get a Grub error is the wrong one is
>  detected first, and does not have a boot loader on it.
>  
>  Mikkel
>  --  
Hi Mikkel

I liked your way of doing things but when I try on my machine as soon as
I use the map command grub gets in a real muddle.
It is not a problem to me but it should work !!!!!!!!!

Even simple things from the grub command start failing

Eg
I can boot into interactive grub from SATA disk
and re enter grub many times as follows

With SATA=(hd0) USB=(hd1)
(SATA is F8 x86-64, USB is F8 i386) both updated to within 3 days.
Both have /dev/sdx1 = /boot, /dev/sdx2 = /, /dev/sdx3 = swap

root (hd0)
chainloader +1
re-enters the SATA grub menu

root (hd1)
chainloader +1
enters the USB grub menu

root (hd1)
chainloader +1
re-enters the USB grub menu

root (hd0)
chainloader +1
re-enters the SATA grub menu

as soon as I do the following grub falls apart !!!!!!!!!!
root (hd0)
map (hd0) (hd1)
map (hd1) (hd0)
chainloader +1

Interesting ?

John

[Bayard Coolidge]

It took me a long time to get F8 booting properly from a
250GB WD MyBook USB drive. The references in this e-mail thread
are excellent, but I was plagued by a problem with the WD
drive falling asleep on me. I am using an HP dv9000z, which
has an AMD Athlon64 X2 at 2GHz, with 2 GB memory and
NVIDIA Go 6150. Ironically, it has two 80GB drives, one with
Windows XP Media Edition, and the other has openSUSE 10.2

I am planning to use the USB drive installation as a "proof of
concept" to ensure that F8 can be configured to work for me on
a day-to-day basis, and once that happens, I plan to scrap openSUSE
and install F8 on the second hard drive, and then use the USB drive
for Rawhide/F9 experimentation.

The keys to getting my USB boot working were 1.) using 'noapic',
2.) Poking a '1' into /sys/block/sda/device/scsi_disk:*/allow_restart
and 3.) adding the following entry into /etc/crontab:
* * * * * root touch /mnt/media/.stayalive; cp /mnt/media/.stayalive
/mnt/media/.stayinalive

The first ('noapic') allowed me to boot my F8 installation long enough
to figure out that it alone wasn't enough to keep the WD drive from
falling asleep after 10 minutes instead of halfway through the boot process.

The second seems to help, but I applied it at the same time as I applied
the third, so I now have to experiment to see what the conclusive fix is.
The second fix didn't seem to work by itself, but I want to see if I needed
to do a reboot (or restart something) for it to be effective.

However, all of this did permit me to fully boot the installation, finish the
initial configuration procedure leftover from the installation, and then have
pup go out and get the latest updates. Note that I installed the Fedora
Unity Respin 20071218-8-x86_64, and booted it into rescue mode to
do an appropriate mkinitrd to include the necessary 'preload=' statements. I have
since been able to get the latest kernel installed as
well as create an updated initrd file, and am looking forward to
completing the system configuration (e.g., ndiswrapper stuff).
At the moment, I'm still having to manually enter the various grub
commands, but I'm confident I can come up with a working menu.lst
or grub.conf file shortly.



       
---------------------------------
Never miss a thing.   Make Yahoo your homepage.

[Miguel Blanco]

Hello,

I managed to play with the installation and I found that
it was almost done! I don't know why it failed first time.

After telling the bios to boot from the USB device
the grub prompt appeared but with no OSes to
boot from. Then I typed the commands to boot
(kernel+initrd+boot) .... and it booted whith no
errors...

I was so happy I decided to write the sample
grub.conf (from John's paper) and afer a few
reboots I updated all the packages available...
and *all* means the kernel too!

That was a mistake (?) and the booting process
stoped not finding something I don't remember now.
And this problem also appear with the original
kernel from f8 ! (?)

I decided to check again the usb disk booting
from the f8 dvd and ... there was no linux system
to be mounted!

And finaly to be able to send you the exact messages
I decided to try to boot in another laptop and write
down the text into this message.... and all works
(both kernels) with no problems at all.... so it seems
hardware related (bad hardware o bad supported hardware).
For the record, where all the problems are shown
is a Dell Inspiron 9400 and where it seems to work
(by now) is a Dell Latitude D620.

I'll look for how well supported are the Dell computers.

Thanks again for your help!

Regards,
Miguel.

2007/12/31, Miguel Blanco <mblancom(a)gmail.com&gt;:
>  Thanks a lot,  John and Mikkel !!
>
>  As soon I can, I'll try again and I'll keep you updated.
>
>  Regards,
>  Miguel
>
>  2007/12/31, John Austin <ja(a)jaa.org.uk&gt;:
>  >
>  > On Mon, 2007-12-31 at 17:00 +0100, Miguel Blanco wrote:
>  > > Ok, I'll try again this time writing down all the steps and repost
>  > > with the exact error. But I'll check, as you propose, the devices
>  > > in /etc/fstab and /boot/grub/grub.conf
>  > >
>  > > Thank you!
>  > >
>  > > Regards,
>  > > Miguel
>  > >
>  > > 2007/12/31, Mikkel L. Ellertson <mikkel(a)infinity-ltd.com&gt;:
>  > > > Miguel Blanco wrote:
>  > > > > Yes, you are rigth about the standard install and the BIOS drives
> remaps!
>  > > > >
>  > > > > I tried configuring GRUB in the MBR of the external disk, and the
> procedure
>  > > > > described in the refered paper failed at the last point, ie. the
> kernel output
>  > > > > a lot of errors and failed to boot...
>  > > > >
>  > > > > Thanks for your comments!
>  > > > >
>  > > > > Regards,
>  > > > > Miguel.
>  > > > >
>  > > > If you get to the point where the kernel loads, and produces errors,
>  > > > then the problem is ether in /etc/fstab or in /boot/grub/grub.conf.
>  > > > Without knowing the errors, it is hard to tell. It probably is a
>  > > > problem with the root device passed to the kernel from Grub. If you
>  > > > are not using LVM, then the root device is probably something like
>  > > > /dev/sdb5 and needs to be changed to /dev/sda5. (The 5 may not be
>  > > > correct.) You may need to do the same thing in /etc/fstab. The
>  > > > reason for this is that the usb_storage module is loaded from
>  > > > initrd, so it becomes the first SCSI controller.
>  > > >
>  > > > A better way to handle it is to give all the partitions on the USB
>  > > > drive labels, and use the labels instead of the device names. That
>  > > > way, it does not matter what drive letter is assigned to the drive.
>  > > >
>  > > > Mikkel
>  > > > --
>  > > >
>  > > >   Do not meddle in the affairs of dragons,
>  > > > for thou art crunchy and taste good with Ketchup!
>  > > >
>  > > >
>  > > > --
>  > > > fedora-list mailing list
>  > > > fedora-list(a)redhat.com
>  > > > To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>  > > >
>  > > >
>  > >
>  > Hi Miguel
>  >
>  > As  Mikkel has stated F8 will install to an external USB by just using
>  > expert mode.
>  > 95% of the reference is unnecessary now.
>  >
>  > I tend not to use LVM but I do pre-partition, pre-format and pre-label
>  > the disk BEFORE starting
>  > the install and the DO NOT format the disk during installation. (which
>  > deletes the labels !)
>  >
>  > The only real decisions are to do with how to boot.
>  >
>  > If the USB disk is to rely on the MBR of a main SATA/IDE type disk then
>  > choose the /dev/sdxy device associated with the USB disk at install
>  > time.
>  > Then add an entry to grub.conf on the fixed disk.
>  > title USB disk
>  >         root (hdp,q)
>  >         chainloader +1
>  >
>  > In addition after install I would then configure grub on the MBR of the
>  > USB disk as well such that I can boot the disk with and without the
>  > presence of the "main", "fixed" disk.
>  >
>  > I did the whole of this on an external USB disk yesterday !!!!
>  >
>  > After first having learnt how to use jigdo to down load
>  > Fedora-Unity-20071218-8-i386-DVD.iso !!!!!!!!
>  >
>  > As stated by Mikkel I had to play with grub interactively to sort out
>  > the correct (hdx,y) !!
>  >
>  > John
>  >
>  > who wrote
>  > http://www.vigla.eclipse.co.uk/usb_install.pdf
>  >
>  >
>  >
>  >
>  >
>  >
>  > --
>  > fedora-list mailing list
>  > fedora-list(a)redhat.com
>  > To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>  >
>

[Miguel Blanco]

Well, all seems to progress as it should ! After updating the BIOS
the Inspiron 9400 works as expected. No more errors with the usb disk!

Thanks again to all of you in special Mikkel an John!

Regards,
Miguel.

2008/1/4, Mikkel L. Ellertson <mikkel(a)infinity-ltd.com&gt;:
>  Miguel Blanco wrote:
>  >> This is strange. Do you remember the exact commands you had to give
>  >> Grub to get it to boot on the 9400? Because it sounds like the USB
>  >> drive is not being mapped as hd0 when booting from the USB drive on
>  >> that machine. That would be a strange BIOS problem...
>  >
>  > Well, I wrote down in paper some of the differences with the John's document
>  > and the relevant part was:
>  >
>  > grub> cat (hd0,2)/boot/grub/tester
>  > (and it worked)
>  > grub> kernel (hd0,2)/boot/vmlinuz-2.6.23.1-42.fc8
>  > grub> initrd (hd0,2)/boot/initrd_usb.gz
>  > grub> boot
>  > (and booted ok)
>  >
>  > and the current grub configuration, which seems to work (allways) on the D620 is
>  >
>  > timeout=10
>  >
>  > title Fedora8initial
>  >       kernel (hd0,2)/boot/vmlinuz-2.6.23.1-42.fc8
>  >       initrd   (hd0,2)/boot/initrd_usb.gz
>  >
>  > title Fedora8-2.6.23.9-85.fc8
>  >       kernel (hd0,2)/boot/vmlinuz-2.63.9-85.fc8
>  >       initrd   (hd0,2)/boot/initrd-2.6.23.9-85.img
>  >
>  > The partions in the usb disk are:
>  > sda1 - NTFS
>  > sda2 - swap
>  > sda3 - Linux
>  >
>  > Regards,
>  > Miguel.
>  >
>  That is about what I would expect on the USB drive. I am just
>  surprised that it does not work on the 9400 when you boot from the
>  USB drive. I would not expect it to work if you boot from a CD or
>  the internal hard drive and chain to the USB drive without Grub
>  doing some remapping first.
>
>  Mikkel
>  --
>
>    Do not meddle in the affairs of dragons,
>  for thou art crunchy and taste good with Ketchup!
>
>
>  --
>  fedora-list mailing list
>  fedora-list(a)redhat.com
>  To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>
>

[Mikkel]

Miguel Blanco wrote:
> > This is strange. Do you remember the exact commands you had to
> give
> > Grub to get it to boot on the 9400? Because it sounds like the USB
> > drive is not being mapped as hd0 when booting from the USB drive on
> > that machine. That would be a strange BIOS problem...
>  
>  Well, I wrote down in paper some of the differences with the John's document
>  and the relevant part was:
>  
>  grub> cat (hd0,2)/boot/grub/tester
>  (and it worked)
>  grub> kernel (hd0,2)/boot/vmlinuz-2.6.23.1-42.fc8
>  grub> initrd (hd0,2)/boot/initrd_usb.gz
>  grub> boot
>  (and booted ok)
>  
>  and the current grub configuration, which seems to work (allways) on the D620 is
>  
>  timeout=10
>  
>  title Fedora8initial
>        kernel (hd0,2)/boot/vmlinuz-2.6.23.1-42.fc8
>        initrd   (hd0,2)/boot/initrd_usb.gz
>  
>  title Fedora8-2.6.23.9-85.fc8
>        kernel (hd0,2)/boot/vmlinuz-2.63.9-85.fc8
>        initrd   (hd0,2)/boot/initrd-2.6.23.9-85.img
>  
>  The partions in the usb disk are:
>  sda1 - NTFS
>  sda2 - swap
>  sda3 - Linux
>  
>  Regards,
>  Miguel.
>   
That is about what I would expect on the USB drive. I am just
surprised that it does not work on the 9400 when you boot from the
USB drive. I would not expect it to work if you boot from a CD or
the internal hard drive and chain to the USB drive without Grub
doing some remapping first.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

[Miguel Blanco]

>  This is strange. Do you remember the exact commands you had to give
>  Grub to get it to boot on the 9400? Because it sounds like the USB
>  drive is not being mapped as hd0 when booting from the USB drive on
>  that machine. That would be a strange BIOS problem... 
Well, I wrote down in paper some of the differences with the John's document
and the relevant part was:

grub> cat (hd0,2)/boot/grub/tester
(and it worked)
grub> kernel (hd0,2)/boot/vmlinuz-2.6.23.1-42.fc8
grub> initrd (hd0,2)/boot/initrd_usb.gz
grub> boot
(and booted ok)

and the current grub configuration, which seems to work (allways) on the D620 is

timeout=10

title Fedora8initial
      kernel (hd0,2)/boot/vmlinuz-2.6.23.1-42.fc8
      initrd   (hd0,2)/boot/initrd_usb.gz

title Fedora8-2.6.23.9-85.fc8
      kernel (hd0,2)/boot/vmlinuz-2.63.9-85.fc8
      initrd   (hd0,2)/boot/initrd-2.6.23.9-85.img

The partions in the usb disk are:
sda1 - NTFS
sda2 - swap
sda3 - Linux

Regards,
Miguel.

[Mikkel]

Miguel Blanco wrote:
>  Hello,
>  
>  I managed to play with the installation and I found that
>  it was almost done! I don't know why it failed first time.
>  
>  After telling the bios to boot from the USB device
>  the grub prompt appeared but with no OSes to
>  boot from. Then I typed the commands to boot
>  (kernel+initrd+boot) .... and it booted whith no
>  errors...
>  
>  I was so happy I decided to write the sample
>  grub.conf (from John's paper) and afer a few
>  reboots I updated all the packages available...
>  and *all* means the kernel too!
>  
>  That was a mistake (?) and the booting process
>  stoped not finding something I don't remember now.
>  And this problem also appear with the original
>  kernel from f8 ! (?)
>  
>  I decided to check again the usb disk booting
>  from the f8 dvd and ... there was no linux system
>  to be mounted!
>  
>  And finaly to be able to send you the exact messages
>  I decided to try to boot in another laptop and write
>  down the text into this message.... and all works
>  (both kernels) with no problems at all.... so it seems
>  hardware related (bad hardware o bad supported hardware).
>  For the record, where all the problems are shown
>  is a Dell Inspiron 9400 and where it seems to work
>  (by now) is a Dell Latitude D620.
>  
>  I'll look for how well supported are the Dell computers.
>  
>  Thanks again for your help!
>  
>  Regards,
>  Miguel.
>   
This is strange. Do you remember the exact commands you had to give
Grub to get it to boot on the 9400? Because it sounds like the USB
drive is not being mapped as hd0 when booting from the USB drive on
that machine. That would be a strange BIOS problem...

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

[Mikkel]

John Austin wrote:
>  On Mon, 2007-12-31 at 12:33 -0600, Mikkel L. Ellertson wrote:
> > What I did was install a copy of Grub to the MBR of the USB drive,
> > and then create an entry like this in the SATA Grub menu:
> >
> > title USB disk
> >       root (hd0)
> >       map (hd0) (hd1)
> >       map (hd1) (hd0)
> >       chainload +1
> >
> > Because of the map commands, the USB drive is hd0 when the chainload
> > command is executed, and it loads Grub from the USB drive. (hd0 is
> > the entire disk, starting from the MBR.) From there it is the same
> > as if you had used the BIOS option to boot from the USB drive. The
> > only thing you have to be careful of is if you have more then one
> > USB drive plugged in. You will get a Grub error is the wrong one is
> > detected first, and does not have a boot loader on it.
> >
> > Mikkel
> > -- 
>  Hi Mikkel
>  
>  I liked your way of doing things but when I try on my machine as soon as
>  I use the map command grub gets in a real muddle.
>  It is not a problem to me but it should work !!!!!!!!!
>  
>  Even simple things from the grub command start failing
>  
>  Eg
>  I can boot into interactive grub from SATA disk
>  and re enter grub many times as follows
>  
>  With SATA=(hd0) USB=(hd1)
>  (SATA is F8 x86-64, USB is F8 i386) both updated to within 3 days.
>  Both have /dev/sdx1 = /boot, /dev/sdx2 = /, /dev/sdx3 = swap
>  
>  root (hd0)
>  chainloader +1
>  re-enters the SATA grub menu
>   
This is because the SATA drive is still mapped as hd0. The pair of
map commands changes that.

>  root (hd1)
>  chainloader +1
>  enters the USB grub menu
>  
>  root (hd1)
>  chainloader +1
>  re-enters the USB grub menu
>  
>  root (hd0)
>  chainloader +1
>  re-enters the SATA grub menu
>  
>  as soon as I do the following grub falls apart !!!!!!!!!!
>  root (hd0)
>  map (hd0) (hd1)
>  map (hd1) (hd0)
>  chainloader +1
>  
>  Interesting ?
>  
>  John
>   
It sounds like Grub on your USB drive is configured to use hd1, not
hd0. The menu entry I gave is for booting from a USB drive that is
configured so you can boot off it using the boot from USB option of
the BIOS. In that case, the USB drive is hd0, not hd1. That is why
you need to remap the drives when booting from the SATA drive, and
chaining to the USB copy of Grub.

One other note - this will work with any bootable USB drive or
memory stick. It does not need to have Grub. It will even work on a
bootable DOS memory stick. (DOS uses the BIOS to access the drive.)
I don't have a USB floppy or CD-ROM drive to test it on, but I would
not expect it to work. On the other hand, Windows in the safe mode
may work. (95, 98 and maybe XP. But probably not Vista.)

One use would be a "pen" drive with OpenDOS configured for BIOS
upgrades.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

[Mikkel]

John Austin wrote:
>  
>  The only real decisions are to do with how to boot.
>  
>  If the USB disk is to rely on the MBR of a main SATA/IDE type disk then
>  choose the /dev/sdxy device associated with the USB disk at install
>  time.
>  Then add an entry to grub.conf on the fixed disk.
>  title USB disk
>  	root (hdp,q)
>  	chainloader +1
>  
>  In addition after install I would then configure grub on the MBR of the
>  USB disk as well such that I can boot the disk with and without the
>  presence of the "main", "fixed" disk.
>   
What I did was install a copy of Grub to the MBR of the USB drive,
and then create an entry like this in the SATA Grub menu:

title USB disk
      root (hd0)
      map (hd0) (hd1)
      map (hd1) (hd0)
      chainload +1

Because of the map commands, the USB drive is hd0 when the chainload
command is executed, and it loads Grub from the USB drive. (hd0 is
the entire disk, starting from the MBR.) From there it is the same
as if you had used the BIOS option to boot from the USB drive. The
only thing you have to be careful of is if you have more then one
USB drive plugged in. You will get a Grub error is the wrong one is
detected first, and does not have a boot loader on it.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

[Dr J Austin]

On Mon, 2007-12-31 at 17:00 +0100, Miguel Blanco wrote:
>  Ok, I'll try again this time writing down all the steps and
> repost
>  with the exact error. But I'll check, as you propose, the devices
>  in /etc/fstab and /boot/grub/grub.conf
>  
>  Thank you!
>  
>  Regards,
>  Miguel
>  
>  2007/12/31, Mikkel L. Ellertson <mikkel(a)infinity-ltd.com&gt;:
>  > Miguel Blanco wrote:
>  > > Yes, you are rigth about the standard install and the BIOS drives remaps!
>  > >
>  > > I tried configuring GRUB in the MBR of the external disk, and the procedure
>  > > described in the refered paper failed at the last point, ie. the kernel output
>  > > a lot of errors and failed to boot...
>  > >
>  > > Thanks for your comments!
>  > >
>  > > Regards,
>  > > Miguel.
>  > >
>  > If you get to the point where the kernel loads, and produces errors,
>  > then the problem is ether in /etc/fstab or in /boot/grub/grub.conf.
>  > Without knowing the errors, it is hard to tell. It probably is a
>  > problem with the root device passed to the kernel from Grub. If you
>  > are not using LVM, then the root device is probably something like
>  > /dev/sdb5 and needs to be changed to /dev/sda5. (The 5 may not be
>  > correct.) You may need to do the same thing in /etc/fstab. The
>  > reason for this is that the usb_storage module is loaded from
>  > initrd, so it becomes the first SCSI controller.
>  >
>  > A better way to handle it is to give all the partitions on the USB
>  > drive labels, and use the labels instead of the device names. That
>  > way, it does not matter what drive letter is assigned to the drive.
>  >
>  > Mikkel
>  > --
>  >
>  >   Do not meddle in the affairs of dragons,
>  > for thou art crunchy and taste good with Ketchup!
>  >
>  >
>  > --
>  > fedora-list mailing list
>  > fedora-list(a)redhat.com
>  > To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>  >
>  >
>   
Hi Miguel

As  Mikkel has stated F8 will install to an external USB by just using
expert mode.
95% of the reference is unnecessary now.

I tend not to use LVM but I do pre-partition, pre-format and pre-label
the disk BEFORE starting
the install and the DO NOT format the disk during installation. (which
deletes the labels !)

The only real decisions are to do with how to boot.

If the USB disk is to rely on the MBR of a main SATA/IDE type disk then
choose the /dev/sdxy device associated with the USB disk at install
time.
Then add an entry to grub.conf on the fixed disk.
title USB disk
	root (hdp,q)
	chainloader +1

In addition after install I would then configure grub on the MBR of the
USB disk as well such that I can boot the disk with and without the
presence of the "main", "fixed" disk.

I did the whole of this on an external USB disk yesterday !!!!

After first having learnt how to use jigdo to down load
Fedora-Unity-20071218-8-i386-DVD.iso !!!!!!!!

As stated by Mikkel I had to play with grub interactively to sort out
the correct (hdx,y) !!

John

who wrote 
http://www.vigla.eclipse.co.uk/usb_install.pdf

[Miguel Blanco]

Ok, I'll try again this time writing down all the steps and repost
with the exact error. But I'll check, as you propose, the devices
in /etc/fstab and /boot/grub/grub.conf

Thank you!

Regards,
Miguel

2007/12/31, Mikkel L. Ellertson <mikkel(a)infinity-ltd.com&gt;:
>  Miguel Blanco wrote:
>  > Yes, you are rigth about the standard install and the BIOS drives remaps!
>  >
>  > I tried configuring GRUB in the MBR of the external disk, and the procedure
>  > described in the refered paper failed at the last point, ie. the kernel output
>  > a lot of errors and failed to boot...
>  >
>  > Thanks for your comments!
>  >
>  > Regards,
>  > Miguel.
>  >
>  If you get to the point where the kernel loads, and produces errors,
>  then the problem is ether in /etc/fstab or in /boot/grub/grub.conf.
>  Without knowing the errors, it is hard to tell. It probably is a
>  problem with the root device passed to the kernel from Grub. If you
>  are not using LVM, then the root device is probably something like
>  /dev/sdb5 and needs to be changed to /dev/sda5. (The 5 may not be
>  correct.) You may need to do the same thing in /etc/fstab. The
>  reason for this is that the usb_storage module is loaded from
>  initrd, so it becomes the first SCSI controller.
>
>  A better way to handle it is to give all the partitions on the USB
>  drive labels, and use the labels instead of the device names. That
>  way, it does not matter what drive letter is assigned to the drive.
>
>  Mikkel
>  --
>
>    Do not meddle in the affairs of dragons,
>  for thou art crunchy and taste good with Ketchup!
>
>
>  --
>  fedora-list mailing list
>  fedora-list(a)redhat.com
>  To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
>
>

[Mikkel]

Miguel Blanco wrote:
>  Yes, you are rigth about the standard install and the BIOS drives
> remaps!
>  
>  I tried configuring GRUB in the MBR of the external disk, and the procedure
>  described in the refered paper failed at the last point, ie. the kernel output
>  a lot of errors and failed to boot...
>  
>  Thanks for your comments!
>  
>  Regards,
>  Miguel.
>   
If you get to the point where the kernel loads, and produces errors,
then the problem is ether in /etc/fstab or in /boot/grub/grub.conf.
Without knowing the errors, it is hard to tell. It probably is a
problem with the root device passed to the kernel from Grub. If you
are not using LVM, then the root device is probably something like
/dev/sdb5 and needs to be changed to /dev/sda5. (The 5 may not be
correct.) You may need to do the same thing in /etc/fstab. The
reason for this is that the usb_storage module is loaded from
initrd, so it becomes the first SCSI controller.

A better way to handle it is to give all the partitions on the USB
drive labels, and use the labels instead of the device names. That
way, it does not matter what drive letter is assigned to the drive.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!

[Mikkel]

Miguel Blanco wrote:
>  Hello!
>  
>  Excuse me if this is a known FAQ, but I can't find any thing related
>  to external usb disk
>  (not USB key, ie. real 2.5" disk) but this
>  http://www.vigla.eclipse.co.uk/usb_install.pdf
>  paper wich refers to an old Fedora Core 3 version.
>  
>  I tried the process described above translating where applicable to F8
>  with no sucess.
>  
>  Do you know whow can I install F8 in an external disk ?
>  
>  Regards,
>  Miguel
>   
You have to use the expert install. The standard install does not
offer to let you use USB drives. The drive will be accessed as a
SCSI drive. (Almost all drives in F8 are accessed as SCSI drives.)
Depending on your system, it will probably be /dev/sdb.

About the only complication is that you want to install Grub to the
USB drive. If you are planning on using the BIOS boot from a USB
device option, you will also have to modify the Grub device map so
that the USB drive is the first BIOS drive. (The BIOS remaps the
drives when you boot from the USB drive.) This is not necessary if
you are chainloading from another Grub install.

Mikkel
-- 

  Do not meddle in the affairs of dragons,
for thou art crunchy and taste good with Ketchup!