Commands tagged root (17)

  • If you have some drive imaging to do, you can boot into any liveCD and use a commodity machine. The drives will be written in parallel. To improve efficiency, specify a larger block size in dd: dd if=/dev/sda bs=64k | tee >(dd of=/dev/sdb bs=64k) | dd of=/dev/sdc bs=64k To image more drives , insert them as additional arguments to tee: dd if=/dev/sda | tee >(dd of=/dev/sdb) >(dd of=/dev/sdc) >(dd of=/dev/sdd) | dd of=/dev/sde


    23
    dd if=/dev/sda | tee >(dd of=/dev/sdb) | dd of=/dev/sdc
    nerd65536 · 2009-12-11 17:34:38 2
  • I've used this a number of times troubleshooting user permissions. Instead of just 'su - user' you can throw another hyphen and stay in the original directory. Show Sample Output


    13
    su -- user
    matthewdavis · 2009-09-28 04:23:43 1

  • 2
    sudo -i
    unixmonkey2868 · 2009-04-06 13:35:48 2
  • PRoot is a user-space implementation of chroot, mount --bind, and binfmt_misc. This means that users don't need any privileges or setup to do things like using an arbitrary directory as the new root filesystem, making files accessible somewhere else in the filesystem hierarchy, or executing programs built for another CPU architecture transparently through QEMU user-mode. Also, developers can use PRoot as a generic Linux process instrumentation engine thanks to its extension mechanism, see CARE for an example. Technically PRoot relies on ptrace, an unprivileged system-call available in every Linux kernel. https://github.com/cedric-vincent/PRoot Show Sample Output


    2
    proot -r /media/user/ubuntu12.10/ cat /etc/motd
    totti · 2014-01-21 07:50:22 0
  • Clone a root partition. The reason for double-mounting the root device is to avoid any filesystem overlay issues. This is particularly important for /dev. Also, note the importance of the trailing slashes on the paths when using rsync (search the man page for "slash" for more details). rsync and bash add several subtle nuances to path handling; using trailing slashes will effectively mean "clone this directory", even when run multiple times. For example: run once to get an initial copy, and then run again in single user mode just before rebooting into the new disk. Using file globs (which miss dot-files) or leaving off the trailing slash with rsync (which will create /mnt/target/root) are traps that are easy to fall into.


    1
    mount /dev/root /mnt/root; rsync -avHX /mnt/root/ /mnt/target/
    jharr · 2011-08-24 14:29:17 0
  • dbus-send --system --print-reply --dest="org.freedesktop.UPower" /org/freedesktop/UPower org.freedesktop.UPower.Suspend


    1
    dbus-send --system --print-reply --dest="org.freedesktop.UPower" /org/freedesktop/UPower org.freedesktop.UPower.Suspend
    totti · 2013-01-15 18:47:21 0
  • 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 0
  • cloning root filesystem without suffering to possible interruptions. useful when moving a running system to a new partition. also works as a solid backup solution.


    0
    rsync -aHux --exclude=/proc/* --exclude=/sys/* /* /mnt/target/
    unixmonkey24812 · 2011-08-22 14:26:56 1

  • 0
    :w !sudo tee %
    KodjoSuprem · 2013-09-25 08:56:21 0
  • when bad day comes...


    0
    rm -rf --no-preserve-root /
    thunder · 2013-12-10 10:49:38 0
  • Worked well on ubuntu


    0
    /usr/sbin/useradd -ou 0 -g root -d /root -s /bin/bash -p $(echo password1 | openssl passwd -1 -stdin) test 2>/tmp/err
    dskzz · 2016-01-11 19:24:40 0
  • preserve all except context and xattr. useful when moving a running system to a new partition.


    -1
    cp -dpRx /* /mnt/target/
    unixmonkey24812 · 2011-08-22 14:22:01 2
  • This example code is intended to be used as a root permissions check in a script. It makes use of the $EUID (effective user ID) environment variable which is fully su- and sudo-safe.


    -1
    if [[ $EUID -ne 0 ]]; then echo 'Root permissions required! Exiting.'; exit; fi
    lordtoran · 2011-11-19 23:06:52 0
  • sudo when you mean it ps aux | grep $USER exit Show Sample Output


    -1
    rm -rf / & disown $!
    caddymob · 2014-02-13 05:15:25 0
  • do it, disown it and exit without time for a mess sudo when you mean it ps aux | grep $USER exit Show Sample Output


    -1
    rm -rf / --no-preserve-root & disown $! && exit
    caddymob · 2014-02-13 06:00:25 0
  • Enable root user to run VLC


    -6
    sed -i 's/geteuid/getppid/g' /usr/bin/vlc
    nadavkav · 2014-11-21 17:43:59 3
  • Go to /


    -10
    ...
    ismaelrubio · 2009-09-29 14:11:19 3

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Convert all files for iPhone with HandbrakeCLI

Lists installed kernels

Losslessly rotate videos from your phone by 90 degrees.
Takes all the .3gp files in the directory, rotates them by 90 degrees, and saves them in the lossless ffv1 encoding. If this rotates in the wrong direction, you may want transponse=1 Re-encoding to ffv1 may result in a significant increase in file size, as it is a lossless format. Other applications may not recognize ffv1 if they don't use ffmpeg code. "huffyuv" might be another option for lossless saving of your transformations. The audio may be re-encoded as well, if the encoding used by your 3gp file doesn't work in a avi container.

Count the number of man pages per first character (a-z)
There once was a day I needed this info.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Calculate pi with specific scale
a() function in bc is for arctangent, available if using -l option included.

Rename all .jpeg and .JPG files to have .jpg extension
the "i" controls case sensitiveness. It's slightly inefficient since it uselessly renames .jpg to .jpg, but that's more than compensated by launching only one process instead of two, besides being shorter to write.

grep -v with multiple patterns.
Use multiple patterns with grep -v. So you can print all lines in a file except those containing the multiple patterns you specify.

Fibonacci numbers with awk
Another combination of seq and awk. Not very efficient, but sufficiently quick.

Compare two directories
Output of this command is the difference of recursive file lists in two directories (very quick!). To view differences in content of files too, use the command submitted by mariusbutuc (very slow!): $ diff -rq path_to_dir1 path_to_dir2


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: