Commands tagged root (17)

  • Duplicate several drives concurrently

    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
  • Change user, assume environment, stay in current dir

    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
  • Root shell


    2
    sudo -i
    unixmonkey2868 · 2009-04-06 13:35:48 2
  • chroot, bind mount without root privilege/setup

    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
  • copy root to new device

    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
  • suspend to ram without root

    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
  • 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 0
  • copy root to new device

    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
  • vim - save document with privileges from vim


    0
    :w !sudo tee %
    KodjoSuprem · 2013-09-25 08:56:21 0
  • Just removes everything

    when bad day comes...


    0
    rm -rf --no-preserve-root /
    thunder · 2013-12-10 10:49:38 0
  • useradd: 1 line, Add new user with root uid, test1:password1 and pipe errors to /tmp/err

    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
  • copy root to new device

    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
  • Terminate script or shell if not launched as root

    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
  • just because I want to take out the dot

    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
  • Delete /

    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
  • run vlc as root

    Enable root user to run VLC


    -5
    sed -i 's/geteuid/getppid/g' /usr/bin/vlc
    nadavkav · 2014-11-21 17:43:59 4
  • Go to /

    Go to /


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

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Count Files in a Directory with Wildcards.
If the dir | wc -l Command not working.

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"

Set file access control lists
The file myfile is owned by tom and has read and write permissions for tom. Group and other permissions are empty which make myfile readable and writable only by tom. setfacl enables user tom to give read permission to user john only. The command 'ls -l' shows a '+' sign telling us that file access control list has been setup for myfile.

bash shortcut: !$ !^ !* !:3 !:h and !:t
When expanding, bash output the command, so don't be affraid if you type the command. Here is the details: First examples: $echo foo bar foobar barfoo First argument: $echo !$ echo barfoo barfoo (Note that typing echo foo bar foobar barfoo && echo !$, bash substitute !$ with $:1) Last argument: $echo foo bar foobar barfoo && echo !^ echo foo bar foobar barfoo && echo barfoo foo bar foobar barfoo barfoo All the arguments: $echo !* echo foo bar foobar barfoo foo bar foobar barfoo The third argument: $echo foo bar foobar barfoo && echo !:3 echo foo bar foobar barfoo && echo foobar foo bar foobar barfoo foobar You may want to add {} for large numbers: echo !:{11} for example Now with path: $echo /usr/bin/foobar /usr/bin/foobar For the head: $echo !$:h echo /usr/bin /usr/bin And the tail: $echo !$:t echo foobar foobar You also may want to try !:h and !:t or !!3-4 for the third and the fourth (so !!:* == !!:1-$)

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" }

Compare a remote file with a local file
Useful for checking if there are differences between local and remote files.

Show all current listening programs by port and pid with SS instead of netstat

find . -name

Hits per hour apache log

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