Re: change default os

[Simon Hobson]

pete tridish wrote:
>- i am helping a farmworkers group to set up a radio studio, and one of the 
>computers was set up with grub, and defaults to linux on reboot.   
>unfortunately, i need it to default to windows--- the linux program we were 
>going to use for the automation was not ready yet, so we switched to windows.  
>I'd rather not wipe out the linux now, since we may switch over when the linux 
>software is ready. 
>
>but the way it stands, any time the power goes out, it boots back in to linux 
>and the guys here get totally lost. the computer stuff needs to work as simply 
>as possible, without much human intervention, because the language barrier is 
>a big issue in keeping the station running. 
>
>how can i change it so that the default OS is windows?   it is grub loader 
>version 1.99

Some of this is Distro dependent, I can only speak for Debian.

If you edit /boot/grub/grub.cfg and change where it says 'set default="0"' to 
the index of teh OS you want to boot, that will do it **BUT** the change will 
be wiped out next time Gurb updates it's config.

To make the change permanent, make the same change in /etc/default/grub and 
then run "update-grub" to update /boot/grub/grub.cfg.

Both these will allow you to change the default OS to boot, but it's done by 
index into the list. If the list changes (such as installing an updated kernel) 
then your index will be wrong and you'll boot something else.

An alternative way is to re-order the components in /etc/grub. On my Debian 
system, Windows (and others) are detected by30_os-prober - if you change the 
numbering so this comes before nn_linux, then the Windows OS will come before 
Linux in the list, meaning Windows will boot by default. You'll need to take 
care to deal with this change any time Grub gets updated and the installer 
wants to put new config files in.