Commands tagged boot (12)

  • Quickly (soft-)reboot skipping hardware checks

    If you are doing some tests which require reboots (e. g. startup skripts, kernel module parameters, ...), this is very time intensive, if you have got a hardware with a long pre-boot phase due to hardware checks. At this time, kexec can help, which only restarts the kernel with all related stuff. First the kernel to be started is loaded, then kexec -e jumps up to start it. Is as hard as a reboot -f, but several times faster (e. g. 1 Minute instead of 12 on some servers here). Show Sample Output


    21
    /sbin/kexec -l /boot/$KERNEL --append="$KERNELPARAMTERS" --initrd=/boot/$INITRD; sync; /sbin/kexec -e
    olorin · 2009-08-03 07:36:49 18
  • show framebuffer console modes to use in grub vga option

    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 6
  • List all installed kernels on Ubuntu except current one

    Lists all installed kernels minus the current one. This is useful to uninstall older kernels that take too much space on /boot partition. Show Sample Output


    4
    dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
    bugmenot · 2021-10-30 22:32:29 389
  • Convert your favorite image in xpm for using in grub

    * 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 7
  • copy hybrid iso images to USB key for booting from it, progress bar and remaining time are displayed while copying


    2
    time (pv file.iso | dd bs=1M oflag=sync of=/dev/sdX 2>/dev/null)
    dash · 2012-01-29 09:44:33 4
  • Remove the boot loader from a usb stick

    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 7
  • Boot from a block device without giving root privilege to Virtual Box

    Usage: VBoxBlockBoot [Virtual_Machine] [Block_device] Eg: VBoxBlockBoot WinXP /dev/sdc In another words vm=usb; usb=sdc;sudo umount /dev/$usb* ; sudo chmod 777 /dev/$usb ; VBoxManage storageattach $vm --medium ~/raw-HD-4-VB/$usb.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm $vm Where vm --> Name of the virtual machine to start usb --> Block device to use. (/dev/sdc) This can used after setup up a boot loader on to my USB pen drive or HDD (After creating Live USB). Here root privilege is needed but not granted to Virtual Box. Thus we can access all our VM.( If we run VBox as root we can't access our VMs). Root privilege is used to - Unmount the storage device - Chmod to full access (777) Requirements:- 1. Device information file (rawvmdk file) created by the following command. Need to run only once. Not bad to run many. VBoxCreateRawDisk() { VBoxManage internalcommands createrawvmdk -filename ~/.rawHD4VB_`basename "$1"`.vmdk -rawdisk "$1"; } 2. Root privilege to umount & chmod 3. Real storage medium (ie /dev/*) (Non-virtual such as USB HD, pen drive, a partition) 4. A virtual m/c already available (here "usb") vm=usb; usb=sdc;sudo umount /dev/$usb* ; sudo chmod 777 /dev/$usb ; VBoxManage storageattach $vm --medium ~/raw-HD-4-VB/$usb.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm $vm VBoxBlockBoot() { sudo umount "$2"*; sudo chmod 777 "$2"; VBoxManage storageattach "$1" --medium ~/.rawHD4VB_`basename "$2"`.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm "$1"; } Show Sample Output


    0
    VBoxBlockBoot() { sudo umount "$2"*; sudo chmod 777 "$2"; VBoxManage storageattach "$1" --medium ~/.rawHD4VB_`basename "$2"`.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm "$1";}
    totti · 2011-07-29 13:04:19 5
  • Boot block devices as virtual devices in Virtual Box

    eg: VBoxManage internalcommands createrawvmdk -filename ~/.VBox_sdc.vmdk -rawdisk /dev/sdc In order to start virtual box using block devices, ( Or to boot from it) run as ROOT sudo VirtualBox Then add & select the vmdk file as a device. At last Start the virtual box. - This cmd needs to run once for a device. - See command 8936 to run with out using ROOT power and easy handling of Virtual m/c


    0
    VBoxManage internalcommands createrawvmdk -filename [path/to/file/name.vmdk] -rawdisk /dev/[block_device]
    totti · 2011-08-19 14:26:22 9
  • Adding kernel boot parameters after loading kernel and initrd

    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 6
  • copy hybrid iso images to USB key for booting from it, progress bar and remaining time are displayed while copying

    Show running time. eta, progressbar Show Sample Output


    0
    pv -petrs $(stat -c %s file.iso) file.iso | dd bs=1M oflag=sync of=/dev/sdX
    f4m8 · 2012-01-30 07:16:29 6
  • copy hybrid iso images to USB key for booting from it, progress bar and remaining time are displayed while copying


    0
    pv file.iso >/dev/sdX
    qiet72 · 2012-01-30 09:38:15 4
  • Fix grub2 boot failure using live cd

    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 4

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Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

ZSH prompt. ':)' after program execution with no error, ':(' after failure.
sorry for my english

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Download mp3 files linked in a RSS podcast feed
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get ip of all running docker containers
pretty self explanitory

Check if a string is into a variable
Returns true (0) if the string is into $var, or false (1) if not.

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