Can't boot Ubuntu after install on HP pavilion

[JeyPeyy]

So I just installed Ubuntu 12.04 on my parent's HP Pavilion. The live-USB works fine and all, but when I rebooted, the computer still thought it was supposed to boot Windows. So I booted the live USB again and used gparted to change the boot flag to the Ubuntu partition. I'm not sure if I should pick the extended partiton or the root partition, so I've tried both and neither works.


ubuntu@ubuntu:~$ sudo fdisk -l

Disk /dev/sda: 750.2 GB, 750156374016 bytes
255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 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 identifier: 0x5d92a095

Device Boot Start End Blocks Id System
/dev/sda1 2048 206847 102400 7 HPFS/NTFS/exFAT
/dev/sda2 206848 586144347 292968750 7 HPFS/NTFS/exFAT
/dev/sda3 586145792 617807871 15831040 7 HPFS/NTFS/exFAT
/dev/sda4 * 617809918 1465147391 423668737 5 Extended
/dev/sda5 617809920 1457651711 419920896 83 Linux
/dev/sda6 1457653760 1465147391 3746816 82 Linux swap / Solaris

Disk /dev/sdb: 1021 MB, 1021125120 bytes
32 heads, 63 sectors/track, 989 cylinders, total 1994385 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 identifier: 0xa1d4dbed

Device Boot Start End Blocks Id System
/dev/sdb1 * 247 1993823 996788+ c W95 FAT32 (LBA)



If I choose the Extended partition (sda4), there's a blinking underscore line in the upper left corner of the screen forever, and if I choose the root partition (sda5), there's a message that tells me it can't find any partition to boot.

So what partition should be flagged, and why wont it work?

[JeyPeyy]

And here's a pic of gparted
http://i.imgur.com/c9SP3.png

[carl4926]

See if supergrubdisk will boot ubuntu

Then use a terminal and do


sudo update-grub

sudo grub-install /dev/sda

[JeyPeyy]

See if supergrubdisk will boot ubuntu

Then use a terminal and do


sudo update-grub

sudo grub-install /dev/sda

Okay so I succeeded to boot Ubuntu from supergrubdisk and I did what you told me, but it still wont work when I reboot. I don't think the problem lies in grub, but rather in BIOS/MBR or the flags.

I'm not very good at those things so I would like to get some help with that.

[JeyPeyy]

I'm not sure why it installed the system under an extended partition. Is it needed? Can I reinstall and make sure it installs without an extended partition?

[jadtech]

the 2 partition look right to me ext4 sda5 for / root and sda6 for swap

as I understand it grub goes to sda

that should give you daul boot windows ubuntu

[darkod]

1. Put the boot flag back to sda1. Windows needs it and linux (grub) doesn't care about the boot flag when it boots.

2. Having ubuntu on logical partitions is fine. The maximum is 4 primary partitions and since you have 3 only for windows, the ubuntu root + swap are logical, the only possible solution (you can't have 5 primary ones). That is not your issue.

3. One thing you can try from terminal in live mode is:

sudo mount /dev/sda5 /mnt
sudo grub-install --root-directory=/mnt /dev/sda

Restart and see if it helped. If it didn't we will take it further.

Don't use supergrub, often it can make things worse.

[carl4926]

Is sda First HD in BIOS boot order

[JeyPeyy]

the 2 partition look right to me ext4 sda5 for / root and sda6 for swap

as I understand it grub goes to sda

that should give you daul boot windows ubuntu

And the boot flag? Should it be on sda4 or sda5? I guess MBR only sees sda1, sda2, sda3 and sda4, right? So if I put the boot flag on sda4, it will boot sda4, but grub is installed on sda5. Therefore it won't boot grub, which is the problem.

[carl4926]

I think the boot flag doesn't matter for windows either if you are using grub, doesn't for me.

[carl4926]

The boot flag on the extended is normal when root is a logical inside it. But more typical with grub legacy distros

[JeyPeyy]

1. Put the boot flag back to sda1. Windows needs it and linux (grub) doesn't care about the boot flag when it boots.

2. Having ubuntu on logical partitions is fine. The maximum is 4 primary partitions and since you have 3 only for windows, the ubuntu root + swap are logical, the only possible solution (you can't have 5 primary ones). That is not your issue.

3. One thing you can try from terminal in live mode is:

sudo mount /dev/sda5 /mnt
sudo grub-install --root-directory=/mnt /dev/sda

Restart and see if it helped. If it didn't we will take it further.

Don't use supergrub, often it can make things worse.

Okay that fixed it. Thanks all!

[darkod]

I think the boot flag doesn't matter for windows either if you are using grub, doesn't for me.

I think you are right. But I still prefer to keep it on the correct partition in case you go back to windows bootloader even temporary one day in need.

[carl4926]

I think you are right. But I still prefer to keep it on the correct partition in case you go back to windows bootloader even temporary one day in need.

Agreed