Changing the booting method?

English Install/Boot/Login
#1

In a double boot laptop with a raid setup at install time I was presented
with a message that I needed to set up a /boot partition with the
partitioner and warning me that unless I knew what I was doing (and I did
not!), linux might not boot.
So, I created the /boot partition.

When presented with the details of the installation, the section of “Booting
from” has at least 2 options: 1) to boot from the MBR or 2) from the boot
partition (there might be another option, from “/” but I am not completely
sure).

Both MBR and /boot options were “disabled”, so I enabled the “/boot” one.
Surely enough the machine would not boot after initial install. :frowning:

I then decided to reinstall all and choose “MBR”. This time everything went
well. :slight_smile:

So finally my question is this: is there a way to set change of boot mode,
without having to reinstall the whole system? For example using the Recovery
mode or similar?
I am not in a hurry to fix anything, but I would like to learn from the
knowledgeable people here if there is such a way. Google did not show me
anything relevant regarding this issue, but perhaps I was not searching the
right terms.

Thanks in advance!

-G-

#2

On 2013-11-20 17:19, -G- wrote:
> In a double boot laptop with a raid setup at install time I was presented

double boot with what, Windows?

In that case it is best not to boot from the MBR, if you intend on doing
Windows service pack updates sometime.

> with a message that I needed to set up a /boot partition with the
> partitioner and warning me that unless I knew what I was doing (and I did
> not!), linux might not boot.
> So, I created the /boot partition.

Was it a primary? If you don’t know, check the number: it must be less
than 5.

> When presented with the details of the installation, the section of “Booting
> from” has at least 2 options: 1) to boot from the MBR or 2) from the boot
> partition (there might be another option, from “/” but I am not completely
> sure).

“/” would not work, per the warning you got.

> Both MBR and /boot options were “disabled”, so I enabled the “/boot” one.
> Surely enough the machine would not boot after initial install. :frowning:
>
> I then decided to reinstall all and choose “MBR”. This time everything went
> well. :slight_smile:
>
> So finally my question is this: is there a way to set change of boot mode,
> without having to reinstall the whole system? For example using the Recovery
> mode or similar?

Yes…

You boot from a rescue system (maybe the rescue xfce image). You
manually mount your “real” system somewhere, with /boot. You bind mount
/proc, /sys, and /dev, then chroot.

At that point you can run YaST (maybe in text mode) and change the boot
options.

–
Cheers / Saludos,

Carlos E. R.
(from 12.3 x86_64 “Dartmouth” at Telcontar)

#3

Carlos E. R. wrote:

> On 2013-11-20 17:19, -G- wrote:
>> In a double boot laptop with a raid setup at install time I was presented
>
> double boot with what, Windows?

Yes, Windows (that was originally in the machine).

> In that case it is best not to boot from the MBR, if you intend on doing
> Windows service pack updates sometime.

Well, that was a problem in my case because trying to set it to boot from
/boot did not work, the message says that “/” will not work either si I had
no other obvious option.

> Was it a primary? If you don’t know, check the number: it must be less
> than 5.

Oh, I see, that is the reason (it is 6).

> You boot from a rescue system (maybe the rescue xfce image). You
> manually mount your “real” system somewhere, with /boot. You bind mount
> /proc, /sys, and /dev, then chroot.
>
> At that point you can run YaST (maybe in text mode) and change the boot
> options.

I see, thank you very much for clarifying this.

-G-

#4

On 2013-11-20 23:49, -G- wrote:
> Carlos E. R. wrote:

>> Was it a primary? If you don’t know, check the number: it must be less
>> than 5.
>
> Oh, I see, that is the reason (it is 6).

Then the trick is to install grub on the extended partition, that
happens to also be a primary.

–
Cheers / Saludos,

Carlos E. R.
(from 12.3 x86_64 “Dartmouth” at Telcontar)