How to choose boot partition without a bootloader?

[JASpup]

These seems a ridiculous question, but I'm stuck on new hardware.

On old hardware I would just run Grub4DOS Bootloader Config and be done with it.

If I have two Puppy partitions and one Ubuntu partition, how do I get off Ubuntu at boot, from Ubuntu?

I see an app called "grub-pc" on Ubuntu/Mint, but it doesn't run. Maybe not an app?

I flagged a Puppy partition "boot" in GParted, but it's still booting Ubuntu.

[backi]

You are using Gub4dos bootloader...right?

Look for menu.lst on your partition(s) .

How looks your menu.lst. Please post it .
..........maybe just edit menu.lst manually (with any Texteditor) from ubuntu .....to change boot sequence in menu.lst.

[JASpup]

You are using Gub4dos bootloader...right?

@backi I am not. Grub4DOS or equivalent is the goal.

I only have whatever is available in Ubuntu at the moment.

[backi]

Look for a (text)file named menu.lst on one of your (boot)partitions..........post it ....

[JASpup]

# This Menu created with Universal USB Installer https://www.pendrivelinux.com
default 0
timeout 0
color NORMAL HIGHLIGHT HELPTEXT HEADING
foreground=FFFFFF
background=000000

title Boot swdl
set ISO=/uui/xenialpup64-7.5-uefi.iso
find --set-root %ISO%
parttype (hd0,3) | set check=
set check=%check:~-5,4%
if "%check%"=="0x00" partnew (hd0,3) 0 0 0
if NOT "%check%"=="0x00" echo ERROR: Fourth partion table is not empty, please delete it if you wish to use this method && pause --wait=5 && configfile /boot/grub/menu.lst
partnew (hd0,3) 0x00 %ISO%
map %ISO% (0xff)
map --hook
root (0xff)
chainloader (0xff)

[taersh]

I think, Ubuntu uses GRUB to boot.
There must be a file like grub.cfg (or similar) probably in a directory named boot.
You'll need to edit this file adding the boot menu entries for Puppy and setting up another default.
Probably a timeout by 10 seconds will give you option to choose which OS to boot.

I'm not sure, though I think installing Grub4DOS will find all OS's that are being installed, if you let Grub4DOS search on all partitions/drives.

Though, please wait before installing Grub4DOS, as there might be an expert step in to proof me wrong or even true.

Edit:

I just saw this /boot/grub/menu.lst in your post above. So, I think you'll need to edit this menu.lst file.

[backi]

Show menu.lst ........can be found in /boot/grub/menu.lst

[Jafadmin]

At it's basic level, a boot process is comprised of this working chain: BIOS->MBR->Bootloader->OS

On startup, the BIOS looks for a disk flagged as a boot disk and hands control over to it's MBR. The MBR looks for the partition with the bootloader (Grub4Dos, Grub2, Syslinux, etc) to which it hands control of the boot process. The bootloader config file then presents a menu that points to the disks, partitions, and directories containing OS's to boot.

The disk containing the OS's doesn't necessarily need a boot flag, an mbr, or a bootloader. Only the boot disk needs these things.

It is not unusual for me to arrange several OS's on a regular (non-boot) disk, and configure a USB flash drive as the boot disk that accesses them.

There are advanced, interesting and exotic combinations of this that chainload other configfiles, bootloaders, and configurations that are most certainly not basic topics. Learn to walk before learning to Tango ..

[JASpup]

@taersh grub.cfg is in /cdrom/boot/grub/

Grub4DOS indeed finds all OS's on a drive.

I don't see it in Ubuntu.

I'm not advanced enough yet to know how to add boot partitions into a configuration file manually.


This is an aside:

Even when a system is functional, I'm finding poles of ueber-technical and neophyte functionality and interface. I accidentally installed Bionic Ubuntu MATE. Briefly: this MATE is nice and better than the Mint version, but MATE still leans neophyte. Puppy/JWM is technical but it really works.

[JASpup]

@Jafadmin erudite understanding but what avenues would you recommend to get out of this?

The .iso burner mounted the Ubuntu partition in the /cdrom folder, but both Puppy partitions are mounted in /media.

I want to boot Puppy.

[JASpup]

Show menu.lst ........can be found in /boot/grub/menu.lst

root@ubuntu-mate:/boot/grub# ls
gfxblacklist.txt grubenv unicode.pf2
root@ubuntu-mate:/boot/grub#

[Jafadmin]

@Jafadmin erudite understanding but what avenues would you recommend to get out of this?

The .iso burner mounted the Ubuntu partition in the /cdrom folder, but both Puppy partitions are mounted in /media.

I want to boot Puppy.

Using what I posted above as a guide, list where each of those key items is arranged on your disk.
Where is the boot flag?
Where is the Bootloader?
Where are the OS's

We need to understand how the DISK is configured before we can help. Boot a puppy distro in ram mode (in memory) and use it to study the disk in question.

[JASpup]

It is my understanding that during an install mainstream distros install a boot loader if you want to keep the existing os. Maybe if I can just do that part without installing the os I can choose a different partition to boot.

[JASpup]

Using what I posted above as a guide, list where each of those key items is arranged on your disk.
Where is the boot flag?
Where is the Bootloader?
Where are the OS's

We need to understand how the DISK is configured before we can help. Boot a puppy distro in ram mode (in memory) and use it to study the disk in question.

/dev/sdc1 XenialPup64
/dev/sdc2 XFCExenialPup
/dev/sdc3 Ubuntu MATE Bionic

The boot flag is on sdc1 where I manually placed it. sdc3 boots.

How do I determine the bootloader?

Each modern distro seems to come with a bootloader for itself, eg, save or no save file, but it's not home to all three partitions' os's.

[Jafadmin]

I recall that the grub4dos installer will do that, and as a bonus will make a backup of the old MBR in the root of the disk.

It has been many years since I used a wizard to create a working boot disk.

Ordinarily I would install MBR & bootloader to the 1st partition on the disk, then use that bootloader's menu to boot OS's on the other partitions:

Code: Select all

sda                  8:32   1   7.5G  0 disk  <- MBR on root device
├─sda1               8:33   1     2G  0 part  <- Bootloader & First OS
├─sda2               8:34   1   2.7G  0 part  <- Second OS
└─sda3               8:35   1   2.8G  0 part  <- Third OS

Use the bootloader menu on sda1 (menu.lst, grub.cfg, syslinux.cfg etc..) to 
configure booting for all partitions on this disk.

If I find a situation that is too messy, I will usually make a fat32 boot thumb with G4D or efi/grub and use that to try and boot the problem OS's on the HDD partitions. That way I can solve without altering the HDD.

[JASpup]

I just tried to install:

root@ubuntu-mate:/boot/grub# grub-install /dev/sdc1
Installing for i386-pc platform.
grub-install: error: failed to get canonical path of `/cow'.
root@ubuntu-mate:/boot/grub#

Your approach might work. Just install Grub4DOS from another booted disk.

I'm wary about this mixing 32/64 bit but maybe it doesn't matter.

[backi]

I'm wary about this mixing 32/64 bit but maybe it doesn't matter.

it does not matter .

[Jafadmin]

The boot flag should be set only on the partition that contains the bootloader. Apparently that is sda3. If so, go to /boot/grub/grub.cfg on sda3 and use the Grub2 bootloader to make entries to boot the other partitions. (Of all the bootloaders, Grub2 is my preferred bootloader, anyway.)

Recognize that the original problem stems from the misconception that all bootloader installers are aware of all other boot configurations and will "just make it work right". None will do that. They all rely on the user having a clear and accurate understanding of the existing disk geometry, the existing boot configuration, and how bootloaders work.

Another common misconception is that changing the boot flag will automatically change the boot partition.

[backi]

Hi jafadmin !
Seems he is an absolute beginner....so we need to be more considerate .

Best in (my humble opinion) would be to install the boot loader with Grub4dosconfig......would be easier to help .because more common.(and the only one i am used to ) .....

but i don`t want to create even more confusion.

[puddlemoon]

Yes I agree @backi
@JASpup the simplest solution for you will be to install gru4dos on sdc (the disk with the boot flag) from another puppy live boot. Then you could refine your setup from there once you understand it better. it's really no risk.
grub4dos is (imo) the easiest to work with and very good at finding your other os's and making a menu for you.

It's the Yin you need...

[Jafadmin]

Hi jafadmin !
Seems he is an absolute beginner....so we need to be more considerate .

Best in (my humble opinion) would be to install the boot loader with Grub4dosconfig......would be easier to help .because more common.(and the only one i am used to ) .....

but i don`t want to create even more confusion.

I'm trying to walk him out of the problem without creating more irreversible changes. That said, If he was certain he wanted to make the sacrifice, then yes, I'd just install G4D on /dev/sdc and select the puppy partition for the bootloader. Easy peasy.

But that will irreversibly blow away all previous boot configurations.

[JASpup]

Strangely I know the GRUB4DOS auto-detection works because I've used it before, but today it's telling me the only installation is Fatdog64.

Not only are there two more distros, that's not the third.

When it comes to multibooting, Puppy and Ubuntu don't mix? 64bit vs 32?

I went GRUB with partitions from multibooting because I thought it was more reliable.

[Jafadmin]

Here's an example of how to boot Ubuntu/Mint from a G4D menu.lst:
(where 86b30d85-22d9-43e2-b000-51e6ecb1afd5 is the UUID of a Mint 17.2 partition)

Code: Select all

title Mint 17.2
  MINT_UUID=86b30d85-22d9-43e2-b000-51e6ecb1afd5
  find --set-root uuid () $MINT_UUID
  kernel /boot/vmlinuz root=UUID=$MINT_UUID  ro quiet splash
  initrd /boot/initrd.img

So, if the G4D wizard doesn't find your ubuntu, just add it by hand to menu.lst

[JASpup]

@jafadmin thinking smart but non-technical:

1) Process is transferable to Puppy partitions with no modifications? (eg, Puppy has no casper)

2) UUID is required and comes from a command or SysInfo report?

3) The app cares about listing order. Does the configuration file?

4) There is a lot more to the file, and also another menu.lst in the Puppy partition's /boot/grub directory. What else could I miss?

The beginning of the new menu.lst:

Code: Select all

# menu.lst produced by grub4dosconfig-v1.9.2
color blue/cyan yellow/blue white/black cyan/black
#splashimage=/splash.xpm
timeout 10
default 0

# Frugal installed Puppy

title Bionic Ubuntu MATE(sdc3/casper)
  find --set-root --ignore-floppies --ignore-cd /casper/initrd
  kernel /casper/vmlinuz   psubdir=casper pmedia=usbflash pfix=fsck
  initrd /casper/initrd

The other issue is I haven't seen the G4D boot menu yet. I'll install it on any partition on that medium to get it to run.

[JASpup]

Show menu.lst ........can be found in /boot/grub/menu.lst

@backi pardon me, before I was on the Ubuntu partition. Here is menu.lst from the XenialPup64 partition:

Code: Select all

# This Menu created with Universal USB Installer https://www.pendrivelinux.com
default 0
timeout 0
color NORMAL HIGHLIGHT HELPTEXT HEADING
foreground=FFFFFF
background=000000

title Boot swdl
set ISO=/uui/xenialpup64-7.5-uefi.iso
find --set-root %ISO%
parttype (hd0,3) | set check=
set check=%check:~-5,4%
if "%check%"=="0x00" partnew (hd0,3) 0 0 0
if NOT "%check%"=="0x00" echo ERROR: Fourth partion table is not empty, please delete it if you wish to use this method && pause --wait=5 && configfile /boot/grub/menu.lst
partnew (hd0,3) 0x00 %ISO%
map %ISO% (0xff)
map --hook
root (0xff)
chainloader (0xff)

How to get this to be recognized by bootloader?

[Jafadmin]

I am not going to be able to be of more help. Sorry.

[JASpup]

I am not going to be able to be of more help. Sorry.

Thanks for the pointers.

[JASpup]

The loader that boots in spite of others is GRUB2.

I found a promising tool called grub-customizer:
https://tipsonubuntu.com/2018/03/11/ins ... 18-04-lts/

It installs but won't run due to a technical error with a high Hackfactor fix.
https://askubuntu.com/questions/254491/ ... ath-of-cow

I got bogged down so am looking for a new route; instead of learning how to boot my extant setup I'm starting over from scratch, looking for a common setup to live dualboot Puppy and Ubuntu.

[JASpup]

Manually modifying grub.cfg with new menu entries leads to two errors upon boot selection:

error: invalid EFI file path
( example: https://ubuntuforums.org/showthread.php?t=2059479 )

error: not an assignment
( example: https://www.linuxquestions.org/question ... nt-751076/ )

Code: Select all

menuentry "Puppy64 Xenial" {
	set root = (hd0, /dev/sdc1)
	chainloader +1	
}

I feel like there's hope to boot Puppy but I'm missing something.

[taersh]

error: invalid EFI file path

Is UEFI/EFI boot activated in BIOS?
Trying to deactivate it does what?