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 Post subject: I cant get grub to display a menu
PostPosted: Wed Mar 09, 2016 11:04 pm 
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In the past I always installed Ubuntu after WinXP or Vista was on a machine - installing along side of Windows. In doing this I always got the grub boot menu in the deal. This time I'm not including a Windows partition at all. I put three small empty primary partitions at the beginning of the drive and then a large extended partition at the end where I instal Ubuntu and linux swap. It is set up the way I want it. However I didn't get a grub boot menu because there was no other OS present when I installed Ubuntu, I don't want to do a grub install because I already have the grub files and directories in the system and I don't think it will get me the boot menu any way. In the past I could install my barebones real mode hobby 'OS' beginning in the boot sector of an empty partition and put the chainloader statement in the grub boot menu entry in grub.cfg file, as follows:

Code:
menuentry "jinx" {
   insmod chain
   set root=(hd0,3)
   chainloader +1
}

Or I could put it in file /etc/grub.d/40_custom and then run grub-mkconfig program. But neither of those now get me a boot menu item for the hobby OS because no boot menu is ever displayed in the first place. QUESTION: how do I get the grub boot menu in my situation?

Thanks. Bill S.


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 Post subject: Re: I cant get grub to display a menu
PostPosted: Thu Mar 10, 2016 12:53 am 
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First result in google for "ubuntu grub config show boot menu"

http://askubuntu.com/questions/16042/how-to-get-to-the-grub-menu-at-boot-time

- Monk


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 Post subject: Re: I cant get grub to display a menu
PostPosted: Thu Mar 10, 2016 9:08 am 
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Location: Maadi, Cairo, Egypt
Keep pressing and releasing shift during BIOS POST and keep doing that until the purple GRUB screen appears. Viola! You have a GRUB boot menu.
Not sure how you make the menu appear automatically, though.

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 Post subject: Re: I cant get grub to display a menu
PostPosted: Thu Mar 10, 2016 11:22 am 
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omarrx024 wrote:
Not sure how you make the menu appear automatically, though.
Show the menu and disable the timeout in grub.cfg:
Code:
set timeout_style=menu
set timeout=-1
bilsch01 wrote:
Or I could put it in file /etc/grub.d/40_custom and then run grub-mkconfig program. But neither of those now get me a boot menu item for the hobby OS because no boot menu is ever displayed in the first place. QUESTION: how do I get the grub boot menu in my situation?
It should be in /etc/grub.d/40_custom and use sudo update-grub to update the grub.cfg file. If you use this method, it will overwrite what I posted above to show the menu; you'll also need to edit /etc/default/grub to specify these options. GRUB_TIMEOUT=-1 is the option to disable the timeout (which implicitly shows the menu as well), although there should be another option to just show the menu without disabling the timeout although I don't know what that option is because the grub menu has always appeared for me even when I've installed Ubuntu on a computer with no other operating systems on it.

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