How to reset dual boot Linux:Win GRUB after "inaccessible boot device"

It's hard to describe, where, in summary, I think I want advice how to
clean up the grub mess.

*How do I clean up Grub such that Grub only sees the latest Windows 10*
(and a soon-to-be-added Ubuntu dual boot?)

Best to do a short history...as there are 7 OS's previously installed.

From memory...
0. Windows works fine on HDD1 and HDD2 as Win7 and then Vista and then
Win10 Pro (all before my time).
1. When I get the PC, I add Ubuntu 16.04 dual boot no problem via Grub.
2. Works fine for years, where I did so many customizations that Win10
would not update for two years, which was fine by me.
3. Finally, a January Win10 update bricked the OS such that even the
Microsoft store couldn't unbrick it but the HDDs were just fine otherwise
and it would boot fine to Ubuntu via Grub.
4. I bought HDD 3 at that time frame and installed a new Win10 Pro which
worked fine for a few months, until I tried to remove Cortana, which
bricked the Win10 but again, the Ubuntu was just fine via Grub.
5. Changed the OS on HDD3 to Win10 & Ubuntu 17.04 around the May or June
time frame (give or take) and all works fine with Grub showing plenty of
operating systems, but only the Win10 and the new and old Ubuntu boot.
6. Desktop works fine for months, where Grub shows so many operating
systems available it's not funny, but really, only the last two (on HDD3
work, plus the older Ubuntu on HDD2 still works via Grub).
7. Two weeks ago, a power outage kills the system while I was working on
it, where the reboot when the power returned (two days later!) was
"inaccessible boot device".
8. I can't fit any more HDDs in the desktop so instead of buying HDD #4 I
just install Windows 10 Pro 1809 on the HDD #3, using the clean install
wiping everything out, where I wiped out the Linux partitions also, just to
start fresh.
9. To keep the installation simple, I disconnect HDD1 and HDD2 and left
them disconnected (because I didn't need them).
10. Today, I need a file on one of the old HDDs, so I power down, connect
the cables to HDD1 and HDD2, but when I boot, I get the "inaccessible boot
device" again. I can get to grub, but it won't boot to any OS now (since
even Ubuntu no longer exists on HDD3 sda1.
11. I power down and disconnect the two HDDs HDD1 and HDD2, and power up,
and everything works fine booting to Windows via Grub (there's no Ubuntu
anymore so the only working OS is this latest Win10 Pro 1809 anyway).
12. While booted to Windows, I re-connect the power to HDD1 and HDD2, and I
can see HDD1 and HDD2 just fine while in Windows 10 Pro 1809 on HDD3 to
get my files (they act like "removable drives" according to the popup when
I connected them while booted).

My question?
*How do I clean up Grub such that Grub only sees the latest Windows 10?*

Asked another way, how do I tell Grub to FORGET about every OS other than
the current Windows 10 1809 on HDD3, and the Ubuntu 17.10 that I plan on
installing on HDD3 soon?

Arlencia's wall of text proves
how much of a dick he is.

arlen holder news Tue, 04 Dec 2018 02:16:16 GMT in alt.os.linux, wrote:

It's hard to describe, where, in summary, I think I want advice
how to clean up the grub mess.

I'm shocked Arlen. I didn't detect one single insult or condescending
remark or comment in your entire post.

*How do I clean up Grub such that Grub only sees the latest
Windows 10* (and a soon-to-be-added Ubuntu dual boot?)

Nor have I seen you claim that only one in one thousand people will
know the answer to your question, this time around.

Best to do a short history...as there are 7 OS's previously
installed.

Wasn't really necessary...

My question?
*How do I clean up Grub such that Grub only sees the latest
Windows 10?*


Ahh. If only you weren't such an asshole in previous threads and
wouldn't continue posting full source code in alt.comp.freeware.

GRUB really isn't difficult to work with. Maybe you need to spend a
little more time learning how to use a search engine, so that you can
tell us what you already tried (fancy that, you trying to do it
yourself before asking someone else to tell you how right?) that
didn't work. Show some initiative.

Or wait for someone who doesn't know you well and who can help to
just offer it up. There's a sucker born every minute, and usenet
isn't in short supply.


--
To prevent yourself from being a victim of cyber
stalking, it's highly recommended you visit he
https://tekrider.net/pages/david-brooks-stalker.php
================================================== =
The road to success is always under construction.

On Tue, 4 Dec 2018 07:33:17 -0000 (UTC), Diesel wrote:

I'm shocked Arlen. I didn't detect one single insult or condescending
remark or comment in your entire post.

Your mother wears army boots while swimming after troop ships.
There now... are you feeling more comfy now that I just insulted you?

Problem with Grub is that it shouldn't even exist since this HDD3 is
supposed to be "only Windows" at this point in time.

So Grub is coming from somewhere else.

On 04/12/2018 03.16, arlen holder wrote:
It's hard to describe, where, in summary, I think I want advice how to
clean up the grub mess.

*How do I clean up Grub such that Grub only sees the latest Windows 10*
(and a soon-to-be-added Ubuntu dual boot?)

Best to do a short history...as there are 7 OS's previously installed.

From memory...
0. Windows works fine on HDD1 and HDD2 as Win7 and then Vista and then
Win10 Pro (all before my time).
1. When I get the PC, I add Ubuntu 16.04 dual boot no problem via Grub.
2. Works fine for years, where I did so many customizations that Win10
would not update for two years, which was fine by me.
3. Finally, a January Win10 update bricked the OS such that even the
Microsoft store couldn't unbrick it but the HDDs were just fine otherwise
and it would boot fine to Ubuntu via Grub.
4. I bought HDD 3 at that time frame and installed a new Win10 Pro which
worked fine for a few months, until I tried to remove Cortana, which
bricked the Win10 but again, the Ubuntu was just fine via Grub.
5. Changed the OS on HDD3 to Win10 & Ubuntu 17.04 around the May or June
time frame (give or take) and all works fine with Grub showing plenty of
operating systems, but only the Win10 and the new and old Ubuntu boot.
6. Desktop works fine for months, where Grub shows so many operating
systems available it's not funny, but really, only the last two (on HDD3
work, plus the older Ubuntu on HDD2 still works via Grub).
7. Two weeks ago, a power outage kills the system while I was working on
it, where the reboot when the power returned (two days later!) was
"inaccessible boot device".
8. I can't fit any more HDDs in the desktop so instead of buying HDD #4 I
just install Windows 10 Pro 1809 on the HDD #3, using the clean install
wiping everything out, where I wiped out the Linux partitions also, just to
start fresh.
9. To keep the installation simple, I disconnect HDD1 and HDD2 and left
them disconnected (because I didn't need them).
10. Today, I need a file on one of the old HDDs, so I power down, connect
the cables to HDD1 and HDD2, but when I boot, I get the "inaccessible boot
device" again. I can get to grub, but it won't boot to any OS now (since
even Ubuntu no longer exists on HDD3 sda1.

It means that you are booting from a different disk, NOT HDD3.

Tell your BIOS to boot the correct one.

--
Cheers, Carlos.

arlen holder wrote:
It's hard to describe, where, in summary, I think I want advice how to
clean up the grub mess.

*How do I clean up Grub such that Grub only sees the latest Windows 10*
(and a soon-to-be-added Ubuntu dual boot?)

Best to do a short history...as there are 7 OS's previously installed.

From memory...
0. Windows works fine on HDD1 and HDD2 as Win7 and then Vista and then
Win10 Pro (all before my time).
1. When I get the PC, I add Ubuntu 16.04 dual boot no problem via Grub.
2. Works fine for years, where I did so many customizations that Win10
would not update for two years, which was fine by me.
3. Finally, a January Win10 update bricked the OS such that even the
Microsoft store couldn't unbrick it but the HDDs were just fine otherwise
and it would boot fine to Ubuntu via Grub.
4. I bought HDD 3 at that time frame and installed a new Win10 Pro which
worked fine for a few months, until I tried to remove Cortana, which
bricked the Win10 but again, the Ubuntu was just fine via Grub.
5. Changed the OS on HDD3 to Win10 & Ubuntu 17.04 around the May or June
time frame (give or take) and all works fine with Grub showing plenty of
operating systems, but only the Win10 and the new and old Ubuntu boot.
6. Desktop works fine for months, where Grub shows so many operating
systems available it's not funny, but really, only the last two (on HDD3
work, plus the older Ubuntu on HDD2 still works via Grub).
7. Two weeks ago, a power outage kills the system while I was working on
it, where the reboot when the power returned (two days later!) was
"inaccessible boot device".
8. I can't fit any more HDDs in the desktop so instead of buying HDD #4 I
just install Windows 10 Pro 1809 on the HDD #3, using the clean install
wiping everything out, where I wiped out the Linux partitions also, just to
start fresh.
9. To keep the installation simple, I disconnect HDD1 and HDD2 and left
them disconnected (because I didn't need them).
10. Today, I need a file on one of the old HDDs, so I power down, connect
the cables to HDD1 and HDD2, but when I boot, I get the "inaccessible boot
device" again. I can get to grub, but it won't boot to any OS now (since
even Ubuntu no longer exists on HDD3 sda1.
11. I power down and disconnect the two HDDs HDD1 and HDD2, and power up,
and everything works fine booting to Windows via Grub (there's no Ubuntu
anymore so the only working OS is this latest Win10 Pro 1809 anyway).
12. While booted to Windows, I re-connect the power to HDD1 and HDD2, and I
can see HDD1 and HDD2 just fine while in Windows 10 Pro 1809 on HDD3 to
get my files (they act like "removable drives" according to the popup when
I connected them while booted).

My question?
*How do I clean up Grub such that Grub only sees the latest Windows 10?*

Asked another way, how do I tell Grub to FORGET about every OS other than
the current Windows 10 1809 on HDD3, and the Ubuntu 17.10 that I plan on
installing on HDD3 soon?

+-----+---------------
1 | MBR | Win7 Vista
+-----+---------------

+-----+---------------
2 | MBR | Windows 10 Ubuntu 16.04 Win10 Inaccessible Boot Device
+-----+---------------

+-----+---------------------------
3 | MBR | Windows 10 Ubuntu 17.04
+-----+---------------------------

====

+-----+---------------------------
3 | MBR | Windows 10 1809
+-----+---------------------------

It sounds like, for some reason, with HDD3 alone, you're booting
from HDD3. (Since you clean installed Windows 10, GRUB is no longer
on HDD3.)

Then, when you connect HDD1 and HDD2 before the boot process begins,
your computer is booting via HDD2. Using popup boot function key,
you should be able to tell it to boot from HDD3, while the
other two disks are present.

To start, it's a matter of entering the BIOS, while
all three hard drives are connected, and specifying HDD3
as the boot device. Then the GRUB on HDD2 can't do anything.

When you install Ubuntu 18.04 on HDD3 soon, you can temporarily
disconnect HDD1 and HDD2, just for the sake of a lack of hair
loss. GRUB will take over HDD3. After installation, power down,
connect HDD1 and HDD2, enter the BIOS, verify HDD3 is the
boot device, and boot. The now-working GRUB on HDD3 will be...
just fine.

Your Inaccessible Boot Device, could have been caused by the
BIOS losing settings during the power outage. Using a multimeter,
clip the black lead onto chassis, touch the red lead to the
top of the CR2032 coin cell, and see if it's at least 3V.
Replace the CR2032 coin cell if it is flat. Verify the SATA
port settings are correct for the Win10 on HDD3 (or it will
go "Inaccessible Boot Volume" as well).

If you lost BIOS power, the SATA ports could revert to a different
setting than the Windows 10 on HDD2 was using. You need to boot
Windows 10 HDD2 in Safe Mode, to allow the drivers to re-load
for the new SATA settings.

Right now, one copy of Windows 10 could be using ATA IDE on the
SATA port, the second Windows 10 could be using the AHCI on SATA.
Since Hot Plug is obviously working, you're probably AHCI in the
BIOS now, which is how you installed Windows 10 on HDD3. You need
to work on the Windows 10 on HDD2 until you get the right
driver to load so it's AHCI too. Safe Mode can be achieved more
than one way, and a BCDEDIT to put the boot menu there is my
preferred method. However, the presence of GRUB and chainloading,
may actually result in Win10 HDD2 no longer presenting the boot menu
(since chainloading "jumps past" that boot menu and jumps
straight into the OS loading stage).

Not a problem. Make a backup copy of the 440 byte boot loader
on HDD2. Copy 440 bytes of HDD3 Windows boot loader to the
MBR of HDD2. Now, if you select HDD2 as the boot device,
the Windows boot menu (assumes Windows boot flag still set)
will take over. Using the Win10 installer DVD, boot to Command
Prompt and set up the boot menu. After the boot to Safe Mode
by pressing F8 in that menu, the next boot to Normal Windows
should resolve the boot issue.

https://winaero.com/blog/enable-the-...in-windows-10/

Now, restore the 440 byte Ubuntu boot loader on HDD2 and it
will take over. And you can chainload that (working) Windows
on HDD2.

By the time you're finished, HDD2 should run independently.
HDD3 should run independently. When you put 18.04 on HDD3,
GRUB will take over there. The runs of update-grub that
occur when the kernel updates on HDD3, will cause the grub
menu building process to include OSes on the other drives.
With some effort on your part, you can improve the quality
of the labels on all OSes, so that the GRUB menu on HDD3
is usable.

Attempts to edit the GRUB menu on HDD3 will be fruitless,
because each kernel upgrade install will only cause update-grub
and re-generate things. I couldn't find any documents to suggest
the GRUB menu build process could be "trimmed" in any way.
Removing OS-prober will prevent GRUB from seeing any Windows
OS, but then it's not much of a multiboot machine any more.

It's the fact that GRUB hasn't evolved to the higher maintenance
model of modern distros, that makes this a mess. Some tweaks
are needed to make this situation more sensible, like a template
for each subtending OS that keeps some sort of user preferences
between rebuilds. The /etc/default/grub has some settings,
but I didn't see enough in there to really control things.

*******

This article

https://help.ubuntu.com/community/Re...tallingWindows

has a pointer to this tool. Nice GUI and everything.

https://help.ubuntu.com/community/Boot-Repair

*******

Some GRUB related commands

sudo update-grub

sudo grub-install /dev/sdX

*******

How to repair GRUB via chrooting from a LiveCD. This
is an "offline" repair of GRUB. Chroot means "Change root"
or in effect, fool the system into seeing the hard drive
component parts as being part of the current slash.
Then, carry out a repair procedure, followed by dismounting
all the fakery. I expect the Boot-Repair above is doing
some of this for you.

https://askubuntu.com/questions/1452...-from-a-livecd

HTH,
Paul

On 04/12/2018 13.56, Paul wrote:
Attempts to edit the GRUB menu on HDD3 will be fruitless,
because each kernel upgrade install will only cause update-grub
and re-generate things. I couldn't find any documents to suggest
the GRUB menu build process could be "trimmed" in any way.
Removing OS-prober will prevent GRUB from seeing any Windows
OS, but then it's not much of a multiboot machine any more.

You can easily create your own menu and disable os-prober.

--
Cheers, Carlos.

On Tue, 04 Dec 2018 18:08:57 +0100, Carlos E.R. wrote:

On 04/12/2018 13.56, Paul wrote:
Attempts to edit the GRUB menu on HDD3 will be fruitless,
because each kernel upgrade install will only cause update-grub
and re-generate things. I couldn't find any documents to suggest
the GRUB menu build process could be "trimmed" in any way.
Removing OS-prober will prevent GRUB from seeing any Windows
OS, but then it's not much of a multiboot machine any more.

You can easily create your own menu and disable os-prober.

Add this to /etc/default/grub

GRUB_DISABLE_OS_PROBER=true

--
Wildman GNU/Linux user #557453
The cow died so I don't need your bull!

On Tue, 04 Dec 2018 07:56:39 -0500, Paul wrote:

It sounds like, for some reason, with HDD3 alone, you're booting
from HDD3. (Since you clean installed Windows 10, GRUB is no longer
on HDD3.)

Hi Paul,
Yes. You are correct. You know the situation better than I do!

HDD3 is supposed to be my boot disk, so it is connected to SATA1.
HDD3 has a clean install of Win10 1809 booted from the ISO optical disc.
Grub2 & Ubuntu 18.04 should be wiped clean off that HDD3 (AFAIK).

Then, when you connect HDD1 and HDD2 before the boot process begins,
your computer is booting via HDD2. Using popup boot function key,
you should be able to tell it to boot from HDD3, while the
other two disks are present.

Ah. This is a good idea!
I just looked, first using the "Escape" boot key.

Trial and error shows the first disk in the list below to be HDD3:
http://www.bild.me/bild.php?file=9539818grub04.jpg
o WDC WD10EZEX
o Toshiba HDWD110
o WDC WD10EFRX
And where I have no idea what this is, given the DVD drive is empty:
o hp DVD-RAM

To start, it's a matter of entering the BIOS, while
all three hard drives are connected, and specifying HDD3
as the boot device. Then the GRUB on HDD2 can't do anything.

Ah. Another good suggestion (why doesn't SATA1 do its job?).
Let me reboot to try this, as I am doing what you suggest in series.

Then I used the F10 key to boot to the BIOS as you suggested.

The funny thing is that the "good" HDD3 disk (which is attached to SATA1)
does seem to be the first in the BIOS boot-order list also.

In fact, the list seems to be the same (not surprisingly in hindsight):
http://www.bild.me/bild.php?file=1696675grub07.jpg
o WDC WD10EZEX
o Toshiba HDWD110
o WDC WD10EFRX

Otherwise I get "inaccessible boot device".
http://www.bild.me/bild.php?file=3246150grub05.jpg

In addition, trial & error shows that HDD3 is sda1 to Grub:
http://www.bild.me/bild.php?file=1139725grub06.jpg
o Ubuntu
o Advanced options for Ubuntu
o Memory test
o Windows 10 (on /dev/sda1)
o Windows 10 (on /dev/sdb1)
o Windows 10 (on /dev/sdc1)

Where I'm not yet sure which disk is sdb1 or sdc1:
http://www.bild.me/bild.php?file=4411450grub01.jpg

Hmmmm... the grub on HDD2 (or HDD1) is doing "something" it shouldn't be
doing, which means, yet again, I don't understand how Grub is found.

Certainly when I boot to Ubuntu, it's the *old* ubuntu, so that Ubuntu
can't be on HDD3.

When you install Ubuntu 18.04 on HDD3 soon, you can temporarily
disconnect HDD1 and HDD2, just for the sake of a lack of hair
loss.

Yes. I agree.
I learned this the hard way already to "simplify" boot installs.
I will likely install Ubuntu 18.10 shortly, after I get grub figured out.

GRUB will take over HDD3. After installation, power down,
connect HDD1 and HDD2, enter the BIOS, verify HDD3 is the
boot device, and boot. The now-working GRUB on HDD3 will be...
just fine.

Yes. I agree.
That's how I *expected* it to work!

Right now, the only good Windows is on HDD3 but there's a good Ubuntu and a
dominant Grub on either HDD2 or HDD1 (I'm not sure which drive it is yet).

Your Inaccessible Boot Device, could have been caused by the
BIOS losing settings during the power outage. Using a multimeter,
clip the black lead onto chassis, touch the red lead to the
top of the CR2032 coin cell, and see if it's at least 3V.

The PC keeps time, which should indicate a good battery, where I don't see
any indication of a bad battery, but I do keep the machine running 24/7 so
I will check the voltage later.

Replace the CR2032 coin cell if it is flat. Verify the SATA
port settings are correct for the Win10 on HDD3 (or it will
go "Inaccessible Boot Volume" as well).

I'm not sure what you mean by "verify the SATA port settings", where I can
only tell you that the HDD3 is on the motherboard SATA1 for sure.

If you lost BIOS power, the SATA ports could revert to a different
setting than the Windows 10 on HDD2 was using. You need to boot
Windows 10 HDD2 in Safe Mode, to allow the drivers to re-load
for the new SATA settings.

Hmmmmmmmmmmm... maybe. I will check the battery as, I guess the two days
without power might have done it. But I can also power down the machine
when not using it, which will check it almost the same.

Right now, one copy of Windows 10 could be using ATA IDE on the
SATA port, the second Windows 10 could be using the AHCI on SATA.
Since Hot Plug is obviously working, you're probably AHCI in the
BIOS now, which is how you installed Windows 10 on HDD3. You need
to work on the Windows 10 on HDD2 until you get the right
driver to load so it's AHCI too. Safe Mode can be achieved more
than one way, and a BCDEDIT to put the boot menu there is my
preferred method. However, the presence of GRUB and chainloading,
may actually result in Win10 HDD2 no longer presenting the boot menu
(since chainloading "jumps past" that boot menu and jumps
straight into the OS loading stage).

That's a bit confusing, where I didn't think, until now, to look at the
"AHCI" settings in BIOS. Let me boot back to BIOS to check... and, since
this is getting long, I'll respond to the rest after reading the quoted
articles first.

Hi Paul, Wildman, and Carlos,

(I will respond to Paul's advice separately, as this is already long.)

Thanks for your good advice:
GRUB_DISABLE_OS_PROBER=true"
Which is what I needed and will take, as much as I understand it, as I
readily admit I never really understood how grub works (since it installs
itself in a dual-boot setup) and where you have explained to me already
more than I knew about my own Grub setup!

This is what Grub found this morning, booting with all 3 HDDs powered on:
http://www.bild.me/bild.php?file=6315743grub_02.jpg
o Ubuntu
o Advanced options for Ubuntu
o Memory test
o Windows 10 (on /dev/sda1)
o Windows 10 (on /dev/sda2)
o Windows 10 (on /dev/sda3)

I have never really understood this "sda" SCSI drive nomenclature since I
never use terms like "sda" except when I'm forced to, so I had assumed
(wrongly it turns out) that sda3 must contain the latest Windows 10, but
choosing sda3 failed to boot no matter what options I tried:
http://www.bild.me/bild.php?file=7780746grub03.jpg
o Preparing Automatic Repair
o Diagnosing your PC
o Your PC did not start correctly

The same sequence happens with sda2, so sda2 and sda3 must be HDD1 and HDD2
(each of which has an "old" Windows 10), where HDD2 definitely also has the
older Ubuntu dual boot setup that I had never bothered to wipe out (but
where I don't know if that HDD2 is sda2 or sda3 yet since I never use sda
SCSI-drive nomenclature except in debugging situations).

The question is "where is grub coming from", given that HDD3 (which
previously had Windows 10 1803 + Ubuntu 18.04) was just "wiped out" a week
or so ago using a Windows 10 1809 ISO to perform a clean install on that
HDD3. [It seems clear that Grub must be coming from HDD2 since that's the
only possibility left!]

After the recent power interruption destroyed Windows 10 1803, I was able
to boot to Ubuntu 18.04, so it was only Windows that was affected by the
power outage.

Nonetheless, I wanted to start both new and clean, so I explicitly
disconnected HDD1 and HDD2 before I booted to a newly made Windows 10 1809
ISO and then I told that Windows 10 1809 boot GUI to destroy the previous
Ubuntu 18.04 partition along with the previous Windows partition (where the
plan is to install Ubuntu 18.10 as the dual boot companion to Windows 1809:
o http://releases.ubuntu.com/18.10/
o http://releases.ubuntu.com/18.10/ubuntu-18.10-desktop-amd64.iso

Given that, I had "thought" (and intended) that I wiped out Grub2 at the
same time, which I probably did ... but only on HDD3 was grub wiped out
(apparently).

Subsequent booting on HDD3 (with both HDD1 and HDD2 disconnected) showed no
hint of Grub, as HDD3 booted right to Windows (where I will add Ubuntu
18.10 soon).

Before I do that, I need to better figure the "boot sequence with grub"
out, since I had "thought" that connecting HDD3 explicitly on the
motherboard SATA1 port was how to tell the computer to boot to that
specific OS (which is the only working windows left).

But somehow, when I connect HDD2 and HDD1, the older Grub (from Ubuntu
17.04) is taking over, which is the sequence I need to try to understand,
since it's certainly an "older grub" that I don't want to be active.

I saw Carlos' suggestion of:
"You can easily create your own menu and disable os-prober."
Where I agree that the 'wrong' grub is running, which is then finding the
"wrong" Windows to attempt the booting process.

And I saw Wildman's suggestion of:
" Add this to /etc/default/grub"
" GRUB_DISABLE_OS_PROBER=true"
Where, in my plan, there should not be a grub in the first place (but
obviously grub exists, even as it's an "older" grub on a non-boot disk).

The interesting question is "where do I find this Grub", since, the HDD3
boot disk, which I specifically attached to the 1st motherboard port
(SATA1) doesn't have grub (as far as I know).

(Obviously, I will research more how to figure out why the 'wrong' grub is
taking over, and then how to stop that grub from activating itself.)

On 05/12/2018 17.21, arlen holder wrote:
Hi Paul, Wildman, and Carlos,

(I will respond to Paul's advice separately, as this is already long.)

Thanks for your good advice:
GRUB_DISABLE_OS_PROBER=true"
Which is what I needed and will take, as much as I understand it, as I
readily admit I never really understood how grub works (since it installs
itself in a dual-boot setup) and where you have explained to me already
more than I knew about my own Grub setup!

This is what Grub found this morning, booting with all 3 HDDs powered on:
http://www.bild.me/bild.php?file=6315743grub_02.jpg
o Ubuntu
o Advanced options for Ubuntu
o Memory test
o Windows 10 (on /dev/sda1)
o Windows 10 (on /dev/sda2)
o Windows 10 (on /dev/sda3)

Wait, the photo you posted is very different from your text above. It
displays:

o Ubuntu
o Advanced options for Ubuntu
o Memory test
o Windows 10 (on /dev/sda1)
o Windows 10 (on /dev/sdb1)
o Windows 10 (on /dev/sdc1)

Those are three different disks, the first partition of each one.



I have never really understood this "sda" SCSI drive nomenclature since I
never use terms like "sda" except when I'm forced to,


sda, sdb, sdc are each a different disk, in hardware. Note: a real
complete disk, not what Windows calls "disk", which often is a single
partition. And they are named in the order the kernel finds them - which
can be different from the order that grub finds them, the bios finds
them, or the boot order. And in fact, the names sda, sdb etc, can apply
to different disks on the next boot. Or not.

Which is why currently in Linux we refer to their UUID, Labels, or paths
instead.


so I had assumed
(wrongly it turns out) that sda3 must contain the latest Windows 10, but
choosing sda3 failed to boot no matter what options I tried:
http://www.bild.me/bild.php?file=7780746grub03.jpg
o Preparing Automatic Repair
o Diagnosing your PC
o Your PC did not start correctly

Well, that's probably your computer manufacturer repair partition. And
it probably fails because it doesn't find the partition layout it
expected to find, or the Windows version it expected to find. Say, you
bought the machine with Windows 8, you installed 10 on your own, well,
the "repair" can no longer work.


The same sequence happens with sda2, so sda2 and sda3 must be HDD1 and HDD2
(each of which has an "old" Windows 10), where HDD2 definitely also has the
older Ubuntu dual boot setup that I had never bothered to wipe out (but
where I don't know if that HDD2 is sda2 or sda3 yet since I never use sda
SCSI-drive nomenclature except in debugging situations).

Notice that Grub doesn't find anything *now*. The grub menu is created
when you run some command in Linux that tells it to update the boot
menu, probably running os-prober (I'm not familiar with Ubuntu). So the
menu that it shows you could be old and not reflect current reality, if
you did not tell Linux to update the grub menu after installing Windows
on HDD3.

Also, when it writes 3 entries named "Windows" doesn't mean that all of
them will boot windows, some of them could be wrong. For example,
Windows can install a small boot partition and then a big system
partition (or disk in Windows parlance). os-prober may list both.


The question is "where is grub coming from", given that HDD3 (which
previously had Windows 10 1803 + Ubuntu 18.04) was just "wiped out" a week
or so ago using a Windows 10 1809 ISO to perform a clean install on that
HDD3. [It seems clear that Grub must be coming from HDD2 since that's the
only possibility left!]

Obviously from HDD2 or HDD1. Just boot each disk separately and find
out, if that is of importance.

And obviously your BIOS boot order doesn't list HDD3 as the first disk
to boot - and no, it being the first SATA connector in your motherboard
is irrelevant, as the order is something that *you* decide and write.


After the recent power interruption destroyed Windows 10 1803, I was able
to boot to Ubuntu 18.04, so it was only Windows that was affected by the
power outage.

Nonetheless, I wanted to start both new and clean, so I explicitly
disconnected HDD1 and HDD2 before I booted to a newly made Windows 10 1809
ISO and then I told that Windows 10 1809 boot GUI to destroy the previous
Ubuntu 18.04 partition along with the previous Windows partition (where the
plan is to install Ubuntu 18.10 as the dual boot companion to Windows 1809:
o http://releases.ubuntu.com/18.10/
o http://releases.ubuntu.com/18.10/ubuntu-18.10-desktop-amd64.iso

Given that, I had "thought" (and intended) that I wiped out Grub2 at the
same time, which I probably did ... but only on HDD3 was grub wiped out
(apparently).

Well, you disconnected the other disks, so grub there was not modified.


Subsequent booting on HDD3 (with both HDD1 and HDD2 disconnected) showed no
hint of Grub, as HDD3 booted right to Windows (where I will add Ubuntu
18.10 soon).

Obviously.


Before I do that, I need to better figure the "boot sequence with grub"
out, since I had "thought" that connecting HDD3 explicitly on the
motherboard SATA1 port was how to tell the computer to boot to that
specific OS (which is the only working windows left).

No.


But somehow, when I connect HDD2 and HDD1, the older Grub (from Ubuntu
17.04) is taking over, which is the sequence I need to try to understand,
since it's certainly an "older grub" that I don't want to be active.

Obviously.


I saw Carlos' suggestion of:
"You can easily create your own menu and disable os-prober."
Where I agree that the 'wrong' grub is running, which is then finding the
"wrong" Windows to attempt the booting process.

It is the correct grub, you told the computer to boot it :-P

Select what disks to boot first he
http://www.bild.me/bild.php?file=9539818grub04.jpg

Note 1: It usually is a list; if the first entry fails, it tries to boot
the second, then the third, till one boots - or none. In that list, HDD3
is not the first.

Note 2: I would suggest to leave HDD3 alone and install Ubuntu on HDD1 or 2.

Note 3: Don't disable os-prober unless you know how to boot the computer
with a broken grub. A mistake puts you out of commission.

--
Cheers, Carlos.

Carlos E.R. wrote:

Select what disks to boot first he
http://www.bild.me/bild.php?file=9539818grub04.jpg

Note 1: It usually is a list; if the first entry fails, it tries to boot
the second, then the third, till one boots - or none. In that list, HDD3
is not the first.

Note 2: I would suggest to leave HDD3 alone and install Ubuntu on HDD1 or 2.

Note 3: Don't disable os-prober unless you know how to boot the computer
with a broken grub. A mistake puts you out of commission.

One reason I'm not analyzing these pictures,
is you have to "build up" your computer, one
piece at a time.

You can't expect to "hammer downwards" and "tame" errant
pieces of this and that, with your magic wand.

If you don't want the other OSes, delete the OS giblets,
so that nobody, not the OS itself, nor any OS-prober, can
detect them.

Clean up the component disks.

Either work on each disk separately, repairing the
broken images on each one.

Or move the data off them (somewhere) and make
data partitions in their place.

To sit around doing "this and that" with that mess
plugged in, is pointless. It's just a big "maintenance time suck".
You'll be constantly hitting the side of the boiler
with your hammer, trying to get heat out of it.

You could, if you wanted, put all the Windows 10 on
one disk drive, and have them managed by the
Windows 10 boot manager.

Put all your Ubuntu distros on one disk drive. Have
them handled by Grub. Disable OS-prober.

Manage the boot using the popup boot menu (select
the Windows disk or the Ubuntu disk).

Many things are possible. They take thought and planning.

But lugging around a set of side-effects, from two
hard drives you're not using, doesn't make sense.
Build a setup that does makes sense. Build a setup
you like, not the one I like.

Just about everything on those disks, can be torn
apart and reassembled, and lashed together again.
And Arlen is the person to do it. A little Macrium
here (partition movement), some LiveCD there, and
you can fix it.

Paul

On Wed, 5 Dec 2018 19:58:51 +0100, Carlos E.R. wrote:

Wait, the photo you posted is very different from your text above. It
displays:

o Ubuntu
o Advanced options for Ubuntu
o Memory test
o Windows 10 (on /dev/sda1)
o Windows 10 (on /dev/sdb1)
o Windows 10 (on /dev/sdc1)

Those are three different disks, the first partition of each one.

Mea culpa.
The pictures are correct.
My transcription was wrong.

The correction is sda1, sdb1, & sdc1, each of which is it's own HDD.

The only working Windows is HDD3 on sda1 (SATA1):
http://www.bild.me/bild.php?file=6315743grub_02.jpg

The other two Windows got corrupted (one by MS, the other by me):
http://www.bild.me/bild.php?file=4411450grub01.jpg

Trial and error shows HDD3 to be "WDC WD10EZEX":
http://www.bild.me/bild.php?file=9539818grub04.jpg

Where HDD3 was already set up in the BIOS to boot first:
http://www.bild.me/bild.php?file=1696675grub07.jpg

What "seems" to be happening is:
o Disconnecting HDD2 & HDD3, Windows boots from HDD3.
o Connecting HDD2 & HDD3, Grub on either HDD2 or HDD3 takes over!

There is a good Ubuntu (an older version) on either HDD2 or HDD3.
That's likely where Grub is coming from.

I'll respond to the rest separately as I wanted to make this correction.

On 05/12/2018 22.57, arlen holder wrote:

Where HDD3 was already set up in the BIOS to boot first:
http://www.bild.me/bild.php?file=1696675grub07.jpg

What "seems" to be happening is:
o Disconnecting HDD2 & HDD3, Windows boots from HDD3.
o Connecting HDD2 & HDD3, Grub on either HDD2 or HDD3 takes over!

Just look at that same bios screen when the three disks are connected.
The first listed and bootable disk will be hdd2 or hdd3.

--
Cheers, Carlos.

Message-ID news
If you don't want the other OSes, delete the OS giblets,
so that nobody, not the OS itself, nor any OS-prober, can
detect them.

Hi Paul,

That is what I want to do, but I'm not sure how to do it gracefully.

I don't need (nor want) the older Windows 10s on HDD1 & HDD2.
http://www.bild.me/bild.php?file=4411450grub01.jpg

I'd be perfectly happy to eliminate the two old Win10 OS giblets!
http://www.bild.me/bild.php?file=8520861grub12.jpg

I booted to Grub and then Linjux to run Carlos' suggested bootinfoscript.
https://github.com/arvidjaar/bootinfoscript/raw/master/bootinfoscript
http://www.bild.me/bild.php?file=9161369grub11.jpg

This script proved:
o HDD3: The only working Windows is on sda (WD10EZEX)
o HDD2: Grub & Ubuntu (17.10) is on sdb (TOSHIBA_HDWD110)
o HDD1: Nothing of use (other than data) is on sdc (WD10EFRX)
http://www.bild.me/bild.php?file=9161369grub11.jpg

That script "thinks" that Windows is "working" on all 3 HDDs.

But the HDD1 & HDD2 Windows are both long gone, never to be recovered.
And I don't care about the Ubuntu since I'll install Ubuntu 18.10 on HDD3.
And, I don't care about the Grub on sda2 either.

The question is what's the most graceful way to clear the OS giblets?
Do I simply wipe out C:\Windows on HDD2 (sdb) and HDD1 (sdc)?
(Is it _that_ easy? Or will that open a new can of worms?)