GRUB Dual Boot SAVEDEFAULT fails with wonky workaround
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						02 Feb 2024 20:16		 -  02 Feb 2024 20:37		#292243
		by y2kdeuce
	
	
		
			
	
	
			 		
													
	
				GRUB Dual Boot SAVEDEFAULT fails with wonky workaround was created by y2kdeuce			
			
				Hello,
I'm a total Linux NOOB. I picked up some old Dell's with parallel ports from a school closing. My plan was to run Windows and Mach 3, and sell off the extras for the same purpose. Some folks suggested these boxes would also be good for LinuxCNC so I thought I'd dip my toe in here to test the waters. To that end, I set up Windows 7 Pro first leaving an unused partition to install Linux CNC.
I grabbed the default debian .iso from the LinuxCNC download page and followed the bouncing ball. All went well. At boot, GRUB fires up and allows m to select the OS I want to boot into. Great! Now I want my selection to be sticky. If I select Windows, I want it to select it every time by default.
The way to accomplish this is supposed to be to set:
GRUB_SAVEDEFAULT=true
GRUB_DEFAULT=saved
in /etc/default/grub
and run:
sudo update-grub
to apply to /boot/grub/grub.cfg.
Did all that but the default doesn't isn't sticky.
Looking at /boot/grub/grubenv the current linux entry is there.
Looking at /boot/grub/grub.cfg I see a function savedefault but nothing calls it.
Workaround was to copy the three menuentries from
/boot/grub/grub.cfg
into
/etc/grub.d/40_custom
adding: savedefault as the first menu item
this addition calls the savedefault function when a menuentry is selected that seems to not be called otherwise.
WHY DO I NEED TO DO ALL THIS?
btw, I also had to block GRUB from calling the files that create the menuentries by setting permissions. Adding a .bak extention was not sufficient
sudu chmod -x /etc/grub.d/10_linux
sudu chmod -x /etc/grub.d/20_linux_xen
sudu chmod -x /etc/grub.d/30_otheros
This is my welcome to Linux. lol
					I'm a total Linux NOOB. I picked up some old Dell's with parallel ports from a school closing. My plan was to run Windows and Mach 3, and sell off the extras for the same purpose. Some folks suggested these boxes would also be good for LinuxCNC so I thought I'd dip my toe in here to test the waters. To that end, I set up Windows 7 Pro first leaving an unused partition to install Linux CNC.
I grabbed the default debian .iso from the LinuxCNC download page and followed the bouncing ball. All went well. At boot, GRUB fires up and allows m to select the OS I want to boot into. Great! Now I want my selection to be sticky. If I select Windows, I want it to select it every time by default.
The way to accomplish this is supposed to be to set:
GRUB_SAVEDEFAULT=true
GRUB_DEFAULT=saved
in /etc/default/grub
and run:
sudo update-grub
to apply to /boot/grub/grub.cfg.
Did all that but the default doesn't isn't sticky.
Looking at /boot/grub/grubenv the current linux entry is there.
Looking at /boot/grub/grub.cfg I see a function savedefault but nothing calls it.
Workaround was to copy the three menuentries from
/boot/grub/grub.cfg
into
/etc/grub.d/40_custom
adding: savedefault as the first menu item
this addition calls the savedefault function when a menuentry is selected that seems to not be called otherwise.
WHY DO I NEED TO DO ALL THIS?
btw, I also had to block GRUB from calling the files that create the menuentries by setting permissions. Adding a .bak extention was not sufficient
sudu chmod -x /etc/grub.d/10_linux
sudu chmod -x /etc/grub.d/20_linux_xen
sudu chmod -x /etc/grub.d/30_otheros
This is my welcome to Linux. lol
		Last edit: 02 Feb 2024 20:37  by y2kdeuce.			
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- tommylight
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						02 Feb 2024 20:30				#292246
		by tommylight
	
	
		
			
	
			
			 		
													
	
				Replied by tommylight on topic GRUB Dual Boot SAVEDEFAULT fails with wonky workaround			
			
				Not your fault, internet is full of useless howtos.
I am a bit fuzzy on this, but there should be a line in /etc/default/grub containing something like default choice = 1
That should be changed to whatever you want set as default, look for entry numbers below where the list starts.
Then sudo update-grub
					I am a bit fuzzy on this, but there should be a line in /etc/default/grub containing something like default choice = 1
That should be changed to whatever you want set as default, look for entry numbers below where the list starts.
Then sudo update-grub
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						02 Feb 2024 20:38				#292247
		by y2kdeuce
	
	
		
			
	
	
			 		
													
	
				Replied by y2kdeuce on topic GRUB Dual Boot SAVEDEFAULT fails with wonky workaround			
			
				if you set GRUB_DEFAULT= to a number it will default to that number.  This workaround will set the default to whatever was used last.			
					
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- rodw
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						04 Feb 2024 02:14				#292351
		by rodw
	
	
		
			
	
			
			 		
													
	
				Replied by rodw on topic GRUB Dual Boot SAVEDEFAULT fails with wonky workaround			
			
				You don't need to do all this the hard way.  the Linuxcnc 2.9.x ISOs have grub-customizer installd
Just type: sudo grub-customizer
Then you can edit your grub menu in a nice drag and drop environment. I usually set it to boot the first entry and set the kernels I want to use under it, then put the rest under a menu entry.
Note that with the later EFI hardware, selecting between Windows and Linux is done at a BIOS Level (on my HP, F9 brings up the boot menu to select between Windows and Grub).
					Just type: sudo grub-customizer
Then you can edit your grub menu in a nice drag and drop environment. I usually set it to boot the first entry and set the kernels I want to use under it, then put the rest under a menu entry.
Note that with the later EFI hardware, selecting between Windows and Linux is done at a BIOS Level (on my HP, F9 brings up the boot menu to select between Windows and Grub).
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