Trying to repair GRUB after Windows installation

[Ianman]

Hi everyone,

Here is my situation. I had a working dual boot setup. Windows 7 was installed first following by Ubuntu 13.04. Everything was working fine until I had to use the Windows 7 installation disc to perform an upgrade. This of course over-wrote my MBR thereby removing Grub. Searching with google I found a number of solutions none of which work because for some reason when I boot with a live USB stick and run:

sudo fdisk -l

I don't see my partitions. If I start GParted it hangs with the message "Scanning all devices". It doesn't seem to be able to find my partitions.

If possible I would like to refrain from re-installing Ubuntu. Does anyone have any ideas?

Thanks!

[sudodus]

Please describe some details of your system!

- Are you using old time BIOS or UEFI?

- Please specify the basic hardware, at least the cpu and ram.

- Which version of Ubuntu 13.04 is it (32-bit or 64-bit)?

- What output do you get from


sudo parted -l

Maybe a good solution would be YannBuntu's Boot-Repair script, but before getting it we should find out which version you need.

http://ubuntuforums.org/showthread.php?t=1769482

[Ianman]

Here is the output from the terminal:


Model: ATA WDC WD10EAVS-00D (scsi)
Disk /dev/sda: 1000GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 1049kB 1000GB 1000GB primary ntfs boot


Model: USB DISK 2.0 (scsi)
Disk /dev/sdb: 2057MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 31.7kB 2056MB 2056MB primary fat32 boot, lba


Model: ATA WDC WD1001FALS-0 (scsi)
Disk /dev/sdc: 1000GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 1049kB 500GB 500GB primary ntfs
2 500GB 1000GB 500GB extended
5 500GB 994GB 494GB logical ext4
6 994GB 1000GB 6431MB logical linux-swap(v1)


This is showing me something weird though. I see that the boot is on what I thought was my secondary disk?

Some other information about my system:

CPU: core i7 920
RAM: 6 GB tripple channel DDR
2 physical hard disks both 1 TB.
I think I am using a BIOS but not too sure. Its an ASUS P6T from 2009 so probably not using the UEFI standard. If I look on the asus site it would indicate a regular BIOS.

Any other information needed?

(Thanks for helping!)

[fantab]

Yes, you are using Legacy BIOS. You have to reinstall Grub. You can do it easily from LiveCD/USB with Boot-Repair (https://help.ubuntu.com/community/Boot-Repair).

Also 494GB for Ubuntu is way too much. Consider splitting into two partitions 30GB for "/" (system files) and the remaining GB for your DATA or /home. I would like to addititonally suggest that you consider installing one OS per HDD. It will help you a lot, especially with kind of issues you are having now.

[sudodus]

Here is the output from the terminal:


Model: ATA WDC WD10EAVS-00D (scsi)
Disk /dev/sda: 1000GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 1049kB 1000GB 1000GB primary ntfs boot


Model: USB DISK 2.0 (scsi)
Disk /dev/sdb: 2057MB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 31.7kB 2056MB 2056MB primary fat32 boot, lba


Model: ATA WDC WD1001FALS-0 (scsi)
Disk /dev/sdc: 1000GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos

Number Start End Size Type File system Flags
1 1049kB 500GB 500GB primary ntfs
2 500GB 1000GB 500GB extended
5 500GB 994GB 494GB logical ext4
6 994GB 1000GB 6431MB logical linux-swap(v1)


This is showing me something weird though. I see that the boot is on what I thought was my secondary disk?

Some other information about my system:

CPU: core i7 920
RAM: 6 GB tripple channel DDR
2 physical hard disks both 1 TB.
I think I am using a BIOS but not too sure. Its an ASUS P6T from 2009 so probably not using the UEFI standard. If I look on the asus site it would indicate a regular BIOS.

Any other information needed?

(Thanks for helping!)

Your Ubuntu is installed on the third (sdc) drive's partition number 5, /dev/sdc5

Where is Windows installed? I guess on /dev/sda1 (or is it on /dev/sdc1 or both?)

I think you have a choice either the use the instructions in the following link

https://help.ubuntu.com/community/Grub2/Installing
(https://help.ubuntu.com/community/Grub2/Installing)or more specifically
https://help.ubuntu.com/community/Grub2/Installing#Fixing_a_Broken_System

or to use the Boot-Repair script, which is more automatic.
http://ubuntuforums.org/showthread.php?t=1769482
(http://ubuntuforums.org/showthread.php?t=1769482)https://help.ubuntu.com/community/Boot-Repair

Good luck :-)

[Ianman]

I tried to use the boot-repair script but it doesn't detect my partitions/disks so that isn't an option for me I am afraid. I don't understand why they are not detected?

I had also considered installing the OS's each on a separate disk but one of the disks is a caviar green which is terrible slow. The reason I gave Ubuntu so much space is because I do a lot of video editing.

Thanks so far guys!

[sudodus]

I tried to use the boot-repair script but it doesn't detect my partitions/disks so that isn't an option for me I am afraid. I don't understand why they are not detected?

I had also considered installing the OS's each on a separate disk but one of the disks is a caviar green which is terrible slow. The reason I gave Ubuntu so much space is because I do a lot of video editing.

Thanks so far guys!

This makes me confused. Obviously parted finds your partitions. But you write that the GUI version, gparted won't. Are you running them from the same operating system? I would think you run them from the USB drive


Model: USB DISK 2.0 (scsi)
Disk /dev/sdb: 2057MB

Anyway, if not, I suggest that you run gparted from the system, where parted works. Otherwise I think it is possible to run the commands described in

https://help.ubuntu.com/community/Grub2/Installing#Fixing_a_Broken_System

from the system where parted can find the partitions.

[jamesisin]

When you are using GParted, are you using the drop-down menu to select between your different drives? First you select the drive using that drop-down (upper-right of GParted) and then you will see the partitions on that drive.

[oldfred]

Parted is showing partition table, but gparted and Boot-Repair are trying to mount partition and that seems like the issue. I might drive fsck from a liveCD.

#From liveCD so everything is unmounted,swap off if necessary, change example shown with partition sdc5 to your partition(s)
#e2fsck is used to check the ext2/ext3/ext4 family of file systems. -p trys fixes where response not required
sudo e2fsck -C0 -p -f -v /dev/sdc5
#if errors: -y auto answers yes for fixes needing response see man e2fsck
sudo e2fsck -f -y -v /dev/sdc5

Check that drive is still sdc, it looks like flash drive became sdb, but that may change depending on what you have plugged in and in what order. If it changes, then change above command to correct drive & partition.