Commands tagged grub (7)

  • This will reboot as the Grub 2 option.


    7
    echo "savedefault --default=2 --once" | grub --batch; sudo reboot
    matthewbauer · 2010-05-02 03:06:23 0
  • look at /boot/grub/menu.lst for somethig like: ## additional options to use with the default boot option, but not with the ## alternatives ## e.g. defoptions=vga=791 resume=/dev/hda5 ## defoptions=vga=795 # defoptions=vga=873 ## altoption boot targets option ## multiple altoptions lines are allowed ## e.g. altoptions=(extra menu suffix) extra boot options ## altoptions=(recovery) single # altoptions=(verbose mode) vga=775 debug # altoptions=(console mode) vga=ask # altoptions=(graphic mode) quiet splash # altoptions=(recovery mode) single vga=(decimal value) is framebuffer mode Show Sample Output


    4
    sudo hwinfo --framebuffer
    hute37 · 2010-10-03 14:45:02 0
  • * size must be 640?480 pixels * only has 14 colors * save it in XPM format Edit /boot/grub/menu.lst and add splashimage=(hd0,0)/boot/grub/grubimg.xpm make sure for your path name and hard disk


    3
    convert image123.png -colors 14 -resize 640x480 grubimg.xpm
    starchox · 2009-03-12 22:55:10 0
  • I like to label my grub boot options with the correct kernel version/build. After building and installing a new kernel with "make install" I had to edit my grub.conf by hand. To avoid this, I've decided to write this little command line to: 1. read the version/build part of the filename to which the kernel symlinks point 2. replace the first label lines of grub.conf grub.conf label lines must be in this format: Latest [{name}-{version/build}] Old [{name}-{version/build}] only the {version/build} part is substituted. For instance: title Latest [GNU/Linux-2.6.31-gentoo-r10.201003] would turn to title Latest [GNU/Linux-2.6.32-gentoo-r7.201004]"


    1
    LATEST=`readlink /boot/vmlinuz`; OLD=`readlink /boot/vmlinuz.old`; cat /boot/grub/grub.conf | sed -i -e 's/\(Latest \[[^-]*\).*\]/\1-'"${LATEST#*-}"]'/1' -e 's/\(Old \[[^-]*\).*\]/\1-'"${OLD#*-}"]'/1' /boot/grub/grub.conf
    algol · 2010-04-21 19:16:51 0
  • If you don't want your computer to try to boot form a USB stick that used to be used as a boot device (maybe for a live linux distro), you will have to remove the boot loader from your stick other wise the boot will fail each time the device is attached to your PC.


    0
    dd if=/dev/zero of=/dev/sdb bs=446 count=1
    dcabanis · 2009-06-07 10:29:49 1
  • Then exit from the shell. exit some time need to exit twice exit exit Now the OS will boot with the new parameters.


    0
    echo "root=/dev/sda7" > /proc/param.conf
    totti · 2011-09-27 18:06:53 1
  • From live CD mount(open) the Ubuntu installed drive. Copy the location (press Ctrl+l, Ctrl+c ) eg: /media/ubuntuuuu Open terminal (Apllication->accessories->terminal) Type this: sudo grub-install --root-directory=/media/ubuntuuuu /dev/sda (replace /media/ubuntuuuu with what u got (ie paste)) Will show success message. Now reboot


    -2
    sudo grub-install --root-directory=/media/ubuntu /dev/sda
    totti · 2011-09-27 17:51:56 0

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Selecting a random file/folder of a folder
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Auto-log commands
A quick alias I use right before logging into a server so that I have a log of the transactions as well as the ability to re-connect from another computer. Useful for when your boss says "what commands did you run again on that server?" and you had already closed the terminal ;) I wrapped it in a script now, with more features, but this is the heart of it. Never leave home without it.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
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C one-liners
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Make a directory named with the current date
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