LinuxQuestions.org - [SOLVED] Dual Boot Windows / CentOS7 problem

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Dual Boot Windows / CentOS7 problem

I have a Toshiba Laptop that had a Dual Boot of Windows 7 and Linux Mint 17 on it and both OS's worked fine. I've been wanting to use CentOS 7 as my primary OS so that I can become more familar with RPM management and proceeded to remove my Mint installation and replace it with the CENTOS 7 installation, and the install completed successfully. HOWEVER, here's my problem.....

When my laptop starts up, I don't see GRUB nor do I have any option of selecting whether to run Windows or CentOS. It automatically loads up Centos 7. When I do a 'sudo fdisk -l', I can see that SDA1 is an NTFS drive, and when I try the following 'sudo mount /dev/sda1 /media/Main\ Drive' I get an error message saying that I can't mount an NTFS drive.

Am I missing something or is there a way to access my Windows files from within Centos. I was able to do this with Mint without an issue, but unable to see any of my windows drives because I can't mount an NTFS drive.

I have no problem with keeping CENTOS as my only OS on this laptop, however, I do need to access the files from the Window's partition, and if anyone can help me to access my files, that would be totally awesome.

Thank you in advance for reading through this and for any help offered.....

Mikey

Simple search found this as first hit - seems to fit the bill.
Haven't tried it - I think I deleted all my CentOS 7 installs.

SYG00 - I did see that when I was doing my research on this, and I did try this and it didn't work for me. I wasn't able to find any of the repo's that these instructions were listing.......

The error I get when trying to mount the NTFS drive is: ''mount: unknown filesystem type 'ntfs' '' - hope this helps with trying to get an answer to this issue.

Thanks again.......

My bad, I should have dug a little more.
You need the ntfs-3g package - have a look at the CentOS wiki page for NTFS here. Follow the instructions for 7 and EPEL - note the link for the repo. Looks like this should do it all for you

Code:

yum install epel-release

yum install ntfs-3g

Can you post here the content of /boot/grub/grub.cfg file?
And output of

Code:

fdisk -l

command?

I don't have a file available at the /boot/grub/grub.cfg - however, when I do an ls on the /boot/grub, I did find a grub2 directory.... could that be part of the problem that there's a grub and a grub2 directory?

Code:

[mikey@localhost boot]$ ls

config-3.10.0-123.13.2.el7.x86_64

config-3.10.0-123.el7.x86_64

grub

grub2

initramfs-0-rescue-7090e266d0cd4645a514b2aea29d63a7.img

...

Here is what I have listed when I use the fdisk -l command:

Code:

[mikey@localhost ~]$ sudo fdisk -l



Disk /dev/sda: 640.1 GB, 640135028736 bytes, 1250263728 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes

Disk label type: dos

Disk identifier: 0x7c438fcb



  Device Boot      Start        End      Blocks  Id  System

/dev/sda1  *        2048    3074047    1536000  27  Hidden NTFS WinRE

/dev/sda2        3074048  999960575  498443264    7  HPFS/NTFS/exFAT

/dev/sda3      999960576  1000984575      512000  83  Linux

/dev/sda4      1000984576  1250263727  124639576    5  Extended

/dev/sda5      1000986624  1250263039  124638208  8e  Linux LVM



Disk /dev/mapper/centos-swap: 6190 MB, 6190792704 bytes, 12091392 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes





Disk /dev/mapper/centos-root: 53.7 GB, 53687091200 bytes, 104857600 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes





Disk /dev/mapper/centos-home: 67.8 GB, 67750592512 bytes, 132325376 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 512 bytes

I/O size (minimum/optimal): 512 bytes / 512 bytes



[mikey@localhost ~]$

SYG00 - I tried your two install commands, and these ones worked out so that I can now access my windows drive from the Centos desktop. Thank you for that.

As for having the dual boot option, I still can't seem to figure out how to get grub to list my windows partition...... any help with this would be much appreciated.

thanks again.
Mikey

The directory may be named as "grub" or "grub2".
Anyway you should have there (under grub or grub2 directory) the configuration file - grub.cfg.

Find that file and check for the value of timeout set in that file. Try to increase it e.g. to 20 secs.
And since you installed ntfs-3g, mount sda1 and sda2 somewhere and run "grub-mkconfig" or "grub2-mkconfig", whichever is suitable for you.
This command will output the presumable menu content into terminal window. Check out whether your Windows found by grub and added to menu or not.
If not, your system probably missed os-prober package. This package needs to recognize Windows installation.

Sorry, completely overlooked that.
Because the NTFS partition couldn't be mounted, the grub setup couldn't locate the Win7 boot files. Now you can, try (as root probably) this and
reboot - first command makes a backup, second rebuilds the boot menu

Code:

cp /boot/grub2/grub.cfg /boot/grub2/grub.cfg.bkp

grub2-mkconfig -o /boot/grub2/grub.cfg

YAY!!!!! you guys are so totally awesome. Thank you for your help as I was able to get my Windows / Centos dual boot working once again with your commands SYG00........

Now onto learning more about Centos 7 and what it can do..........

Thanks again everyone......
Mikey

Hello everyone, I just wanted to confirm these steps above resolved the exact same issue with my system. Added the epel repo; installed ntfs; mounted the two Window 7 partitions; used cp command to create a backup; issued the 'grub2-mkconfig -o /boot/grub2/grub.cfg' command. Thanks!