Re: is booting an OS without power cycling a host possible?

[Leslie S Satenstein]

I am a little confused. Currently I have a grub.cfg that has three operating systems in the list.  If I reboot, the default value setting boots that operating system.

So, if I am right, all that is required is for the system that is handing over control, to change the default setting in the grub.cfg file.

Is that not what is wanted and what solves the problem^

 

------------------

Regards

 Leslie

Mr. Leslie Satenstein
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From: Arbiel Perlacremaz <address@hidden>
To: Peter Van Wieren <address@hidden>; address@hidden
Sent: Saturday, March 17, 2012 4:58 PM
Subject: Re: is booting an OS without power cycling a host possible?

I do not quite understand what you want to do. Is that that, in a first
stage, you want to boot distribution A, and then, in a second stage,
switch to distribution B, as though you had directly booted distribution B.

This is definitely not possible.

Now, there is no difficulty to have grub2 (for Grub Legacy, you may be
speaking of, I really don't know) residing on a drive to boot a
distribution located on another drive.

So, please, clarify the situation you are in.

Arbiel

Le 17/03/2012 19:33, Peter Van Wieren a écrit :
> I have a host with linux distribution "A".  The host is presently running "A", and has already been started by grub.  There exists, on a second hard disk drive, linux distribution "B" is installed but not mounted.
>
> I hoped I could transition from "A" to "B", without power cycling the host or editing the MBR, by running grub from the command line as root.  In a root shell I started grub and planned to issue the commands:
>
>    1) root (hd1,0)
>    2) kernel .... vmlinuz
>    3) initrd ....
>    4) boot
>
> My hope was that distribution "B" would boot, and "A" would somehow be abolished.  I do not know for sure if the above is supposed to even be possible or not.  Can it be done?
>
> I made it to step #3.  The trouble is the "initrd" command returns "Error 16: inconsistent filesystem"
>
>
>
> P.S. Why would I want to do this?  Answer: I threw my old USB keyboard in the trash, and replaced it with a new one.  It was all well and good, until I found that the new keyboard doesn't work at all during the BIOS or GRUB stages -- the new keyboard only works after the OS has been booted.  Thus if I change the default option in grub.conf to "B" and something doesn't work, my host will become completely useless until such a time as I can locate a 2002 era USB keyboard -- which in theory should work in the BIOS and GRUB stages.
>
> Thanks,
> Pete
>
> _______________________________________________
> Help-grub mailing list
> address@hidden
> https://lists.gnu.org/mailman/listinfo/help-grub

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