Thread: Reinstall GRUB through a Specific Partition?

sorry title's confusing, couldn't figure out better way it. triple boot computer: ubuntu 11.04, windows 7, , ubuntu 12.04 (all 64-bit). of grub settings "on" ubuntu 11.04 partition, whenever grub gets updated on 12.04 partition, of grub customizations overwritten. i'll link thread made while ago has few grub fixes have saved life (well, not saved life, idea):
http://ubuntuforums.org/showthread.php?t=1873849

used in order fix problem:

code:

sudo grub-setup /dev/sda

i'm pretty sure that's used do, , worked perfectly. however, when now, laptop bootloops when start up; runs asus splash screen, when grub menu supposed appear, computer restarts instead. luckily, know fix. use bootable flash drive (ubuntu 12.04) , run through terminal (replace "/dev/sda5" partition has preferred grub settings, , replace "/dev/sda" hard drive; these can found in gparted):

code:

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

does know way fix don't have go through whole process of booting flash drive?

well, actually, had idea. instead of running through primary partition,

code:

sudo grub-setup /dev/sda

should run this?

code:

sudo grub-install /dev/sda

if that's problem, need 1 of easy buttons staples.

should have listened oldfred on 1 of other threads:
http://ubuntuforums.org/showthread.php?t=1872283

said this:

posted oldfred

your second install of ubuntu write grub2 boot loader mbr , booting it. os-prober should find both windows , other install.

may have issues on grub2 updates both systems set rewrite grub2 boot loader mbr.

have several / (roots) in sdc drive have installed many versions of ubuntu , not overwritten older ones.

may want make shared ntfs partition data. data can used windows (d: ) , both installs of ubuntu. have firefox & thunderbird profiles in shared ntfs partition have same bootmarks & email in whatever system boot.

#to grub remember reinstall on updates:
sudo dpkg-reconfigure grub-pc
#enter thru first pages,spacebar choose/unchoose drive, enter accept, not choose partitions
#to see drive grub2 uses see line - grub-pc/install_devices:
sudo debconf-show grub-pc

1 user posted long time ago.

i found out how prevent mbr overwritten.
ran dpkg-reconfigure grub-pc , deselected /dev/sda meant values field grub-pc/install_devices in /var/cache/debconf/config.dat empty. nothing written mbr or boot sector when grub-pc gets updated. should rerun manually grub-install /dev/sda2 after grub-pc package updates keep 'stage1' install in sync.

one thing tricked me that, when going through first few pages, have hit "tab" , "enter." trying figure out special key went next page, have hit "tab" highlight "ok" button (you can't click mouse).

if can boot other install 1 not in mbr.

#reinstall working (not livecd) system
sudo grub-install /dev/sda

otherwise 2 commands mount , install work reset it.

grub remembers drive's mbr reinstall to. major update reinstall grub mbr.

#to see drive grub2 uses see line - grub-pc/install_devices:
sudo debconf-show grub-pc

#to grub2 remember reinstall on updates:
sudo dpkg-reconfigure grub-pc
#enter thru first pages,spacebar choose/unchoose drive, enter accept, not choose partitions

think can unchoose blank out setting or choose partition (even though not recommended) throwaway, not overwrite mbr want keep install.

have grub.cfg , grub in usb flash drive configured boot hard drive. have manually configure grub.cfg.

install grub2 usb -general info
http://members.iinet.net/~herman546/....html#grub_usb

Forum The Ubuntu Forum Community Ubuntu Official Flavours Support Installation & Upgrades [SOLVED] Reinstall GRUB through a Specific Partition?

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