Windows boot option missing from Boot manager on installatio

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ChrisTheBA
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Joined: 2014/06/10 22:05:16

Windows boot option missing from Boot manager on installatio

Post by ChrisTheBA » 2014/10/24 18:48:06

I upgraded/wiped my CentOS 6.5 system, went over the disk configuration options over and over and I, or it, couldn't get it right.

On startup, my Windows boot on Disk 0 was gone, no sign of it.
The CENTOS boot option was the only one, which works fine to Disk 1. (It IS still named centos65, I never quite did catch where the server name was, maybe that's something else unclear...)

Considering the amount of time I spent re-checking this, I think it's a problem. Considering the boot manager _must_ be sitting on Disk 0 it's confusing that it lost the OS. I'm a little panicked that it may have wiped it completely. Being a Sandbox PC it's not a crushing loss.

Being a lifelong windows person, I'll be going to look up how it is you fix bootmgr to add an OS to the list....<sigh> Hate to use the Windows CD to fix this, since I'm trying to get up to speed on Linux....

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TrevorH
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Re: Windows boot option missing from Boot manager on install

Post by TrevorH » 2014/10/24 20:22:46

El7 no longers adds Windows partitions to the menu automatically. Ask Redhat why not :-(

You can add something to do so by editing a script in /etc/grub.d. I have a /etc/grub.d/15_windows that is a) executable and b) looks like

Code: Select all

#!/bin/bash -e
echo "Adding Windows" >&2
cat <<EOF
menuentry "Windows 7" {
set root='hd0,msdos1'
chainloader +1
}
EOF
The root='hd0,msdos1' will probably need to change unless, like mine, yours is on the first partition of the first phyiscal disk.
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ChrisTheBA
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Joined: 2014/06/10 22:05:16

Re: Windows boot option missing from Boot manager on install

Post by ChrisTheBA » 2015/01/22 21:22:12

I actually just gave up and reinstalled centos65, it found and added my Windows OS.

This does look pretty close to what I got on re-installation:
in /etc/grub.conf
-tons of gobbly related to centos then-
title Other
rootnoverify (hd0,0)
chainloader +1

Selecting Other gets me my old Windows XP OS.

owl102
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Re: Windows boot option missing from Boot manager on install

Post by owl102 » 2015/01/24 10:27:45

TrevorH wrote:El7 no longers adds Windows partitions to the menu automatically. Ask Redhat why not :-(
This does not seem to be completely true. After installing ntfs-3g from epel and "grub2-mkconfig -o /boot/grub2/grub.cfg" os-proper did find Windows 7 and inserted it into grub boot menu automatically. (And I assume this will work with Windows XP, too.)
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sqa4life
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Re: Windows boot option missing from Boot manager on install

Post by sqa4life » 2015/02/05 00:29:43

I am sorry, can you please provide some details steps on how to fix this?

I've just installed CentOS 7 and my windows 7 boot is gone. Only the CentOS linux boot option is available.

thank you.
newbie

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Vladi
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Location: Nyíregyháza/Hungary/EU

Re: Windows boot option missing from Boot manager on install

Post by Vladi » 2015/02/05 11:06:01

owl102 wrote:
TrevorH wrote:El7 no longers adds Windows partitions to the menu automatically. Ask Redhat why not :-(
This does not seem to be completely true. After installing ntfs-3g from epel and "grub2-mkconfig -o /boot/grub2/grub.cfg" os-proper did find Windows 7 and inserted it into grub boot menu automatically. (And I assume this will work with Windows XP, too.)
I find it too. I think anaconda cant see ntfs withoute driver. After adding ntfs-3g and grub costumiser gui, it was automatic.

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Vladi
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Re: Windows boot option missing from Boot manager on install

Post by Vladi » 2015/02/05 11:09:35

sqa4life wrote:I am sorry, can you please provide some details steps on how to fix this?

I've just installed CentOS 7 and my windows 7 boot is gone. Only the CentOS linux boot option is available.

thank you.
newbie
Install epel repo:link
install ntfs-3g driver from it.
Install Grub Customizer it will automaticly find your win. enable it, reboot.

owl102
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Re: Windows boot option missing from Boot manager on install

Post by owl102 » 2015/02/11 10:41:10

Vladi wrote:Install epel repo:link
Since epel-release has gotten part of CentOS 7 it's even easier than that, a simple "yum install epel-release" will add the epel repository.

So in total we have (enter as root):

Code: Select all

yum install epel-release
yum install ntfs-3g os-prober
grub2-mkconfig -o /boot/grub2/grub.cfg
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slacka
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Joined: 2015/04/13 03:25:44

Re: Windows boot option missing from Boot manager on install

Post by slacka » 2015/09/15 08:04:55

owl102 wrote:
Vladi wrote:Install epel repo:[url=https://fedoraproject.org/wiki/EPEL
So in total we have (enter as root):

Code: Select all

yum install epel-release
yum install ntfs-3g os-prober
grub2-mkconfig -o /boot/grub2/grub.cfg
Thank you! This worked, but now my system is using the original 7.1 kernel because of this bug. CentOS version

I tried the patch in the bug report to /usr/share/grub/grub-mkconfig_lib and my boot order is still screwed up. I'm probably missing a step, so I ended up manually editing grub.

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toracat
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Re: Windows boot option missing from Boot manager on install

Post by toracat » 2015/09/27 14:45:19

slacka wrote: Thank you! This worked, but now my system is using the original 7.1 kernel because of this bug. CentOS version

I tried the patch in the bug report to /usr/share/grub/grub-mkconfig_lib and my boot order is still screwed up. I'm probably missing a step, so I ended up manually editing grub.
slacka,

This [boot order] is a separate issue and you should have started a new topic. Anyway, the problem has been resolved in grub2-2.02-0.17.el7_1.4 as noted in CentOS bug #7651 you referenced.
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