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Commands using sudo from sorted by
Terminal - Commands using sudo - 415 results
on the listening side: sudo nc -lp 2022 | sudo tar -xvf - and on the sending side: tar -cvzf - ./*| nc -w 3 name_of_listening_host 2022
2009-03-27 09:59:33
User: smcpherson
Functions: sudo tar
Tags: netcat
-2

This is useful for sending data between 2 computers that you have shell access to. Uses tar compression during transfer. Files are compressed & uncompressed automatically. Note the trailing dash on the listening side that makes netcat listen to stdin for data.

on the listening side:

sudo nc -lp 2022 | sudo tar -xvf -

explanation: open netcat to -l listen on -p port 2022, take the data stream and pipe to tar -x extract, -v verbose, -f using file filename - means "stdin"

on the sending side:

tar -cvzf - ./*| nc -w 3 name_of_listening_host 2022

explanation: compress all files in current dir using tar -c create, -v verbose, -f using file, - filename - here means "stdout" because we're tar -c instead of tar -x, -w3 wait 3 seconds on stream termination and then end the connection to the listening host name_of_listening_host, on port 2022

function nuke() { if [ $(whoami) != "root" ] ; then for x in $@; do sudo apt-get autoremove --purge $x; done; else for x in $@; do apt-get autoremove --purge $x; done; fi }
2009-03-25 23:21:21
User: ruinbox
Functions: sudo
Tags: sudo apt-get
1

You can't stand programs x, y, and z. Remove all trace of their existence by adding this function to your config. It will remove the cruft, the settings, and such and such. This function doesn't even give a damn about you trying to remove programs that don't exist: it'll just for loop to the next one on your hit list.

wget -q http://xyz.gpg -O- | sudo apt-key add -
2009-03-25 12:18:36
User: gnuyoga
Functions: sudo wget
Tags: wget apt-key
4

when we add a new package to a aptitude (the debian package manager) we need to add the gpg, otherwise it will show warning / error for missing key

wget -q http://xyz.gpg -O- | sudo apt-key add -
2009-03-25 12:18:29
User: gnuyoga
Functions: sudo wget
Tags: apt-key
2

when we add a new package to a aptitude (the debian package manager) we need to add the gpg, otherwise it will show warning / error for missing key

ps ax | grep <processname> | grep -v grep | awk '{print $1}' | sudo xargs kill -9
sudo zcat /var/log/auth.log.*.gz | awk '/Failed password/&&!/for invalid user/{a[$9]++}/Failed password for invalid user/{a["*" $11]++}END{for (i in a) printf "%6s\t%s\n", a[i], i|"sort -n"}'
2009-03-21 06:41:59
Functions: awk printf sudo zcat
22

Show the number of failed tries of login per account. If the user does not exist it is marked with *.

sudo dmidecode --type 17 | more
sudo lsof -i :<port>
sudo find / -iname "*.lproj" -and \! -iname "en*" -print0 | tee /dev/stderr | sudo xargs -0 rm -rfv
2009-03-09 22:08:45
User: asmoore82
Functions: find rm sudo tee xargs
3

This will get the job done in the most efficient way -

spawning only one `rm` process.

"On-the-fly" find data is displayed through `tee` and

you should have plenty of time to ctrl-c if needed before it's too late.

You may need to re-run this after major Software Updates.

To leave more languages in, add more ``-and \! -iname "lang*"'' statements:

sudo find / -iname "*.lproj" -and \! -iname "en*" -and \! -iname "spanish*" -print0 | tee /dev/stderr | sudo xargs -0 rm -rfv

**Edit: note the 2nd sudo near the end of the pipeline - this is necessary.

sudo cat /proc/kcore | strings | awk 'length > 20' | less
2009-03-09 02:19:47
User: nesquick
Functions: awk cat strings sudo
Tags: cat ram strings
15

This command lets you see and scroll through all of the strings that are stored in the RAM at any given time. Press space bar to scroll through to see more pages (or use the arrow keys etc).

Sometimes if you don't save that file that you were working on or want to get back something you closed it can be found floating around in here!

The awk command only shows lines that are longer than 20 characters (to avoid seeing lots of junk that probably isn't "human readable").

If you want to dump the whole thing to a file replace the final '| less' with '> memorydump'. This is great for searching through many times (and with the added bonus that it doesn't overwrite any memory...).

Here's a neat example to show up conversations that were had in pidgin (will probably work after it has been closed)...

sudo cat /proc/kcore | strings | grep '([0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\})'

(depending on sudo settings it might be best to run

sudo su

first to get to a # prompt)

echo "Whatever you need" | sudo tee [-a] /etc/system-file.cfg
2009-03-09 01:33:31
User: asmoore82
Functions: echo sudo tee
4

only for sudo-style systems.

Use this construct instead of I/O re-directors ``>'' or ``>>'' because

sudo only elevates the commands and *not* the re-directors.

***warning: remember that the `tee` command will clobber

file contents unless it is given the ``-a'' argument

Also, for extra security, the "left" command is still run unprivileged.

sudo find / -type f \( -perm /4000 -a -user root \) -ls -o \( -perm /2000 -a -group root \) -ls
2009-03-02 18:48:17
User: atoponce
Functions: find sudo
2

Discovering all executables on your system that can be run as another user, especially root, is critical for system security. The above command will find those files with have SUID or SGID bits set and are owned by the root user or group.

sudo find / -mmin 60 -type f
2009-03-01 23:03:31
User: atoponce
Functions: find sudo
28

Useful mainly for debugging or troubleshooting an application or system, such as X11, Apache, Bind, DHCP and others. Another useful switch that can be combined with -mmin, -mtime and so forth is -daystart. For example, to find files that were modified in the /etc directory only yesterday:

sudo find /etc -daystart -mtime 1 -type f
sudo mount -o remount,rw /
2009-03-01 13:36:05
User: blindgaenger
Functions: mount sudo
Tags: mount remount rw
4

Saved my day, when my harddrive got stuck in read-only mode.

sudo dd if=/dev/sda of=/media/disk/backup/sda.backup
2009-02-27 20:23:37
User: bandit36
Functions: dd sudo
Tags: backup dd
14

This will create an exact duplicate image of your hard drive that you can then restore by simply reversing the "if" & "of" locations.

sudo dd if=/media/disk/backup/sda.backup of=/dev/sda

Alternatively, you can use an SSH connection to do your backups:

dd if=/dev/sda | ssh user@ssh.server.com dd of=~/backup/sda.backup
sudo ufw allow proto tcp from 1.2.3.4 to any port 80
function miso () { mkdir ~/ISO_CD && sudo mount -o loop "$@" ~/ISO_CD && cd ~/ISO_CD && ls; } function uiso () { cd ~ && sudo umount ~/ISO_CD && rm -r ~/ISO_CD; }
2009-02-25 03:41:35
User: vududevil
Functions: cd mkdir mount rm sudo umount
4

Add the functions to the .bashrc to make it work

Example: First go to the iso file directory and type:

----------------------------------------------------------------------------------------------------

user@box:~$ miso file.iso

----------------------------------------------------------------------------------------------------

It will put you into a temporary mounting point directory (ISO_CD) and will show the files

You can umount the iso file whatever the directory you are

----------------------------------------------------------------------------------------------------

user@box:~/ISO_CD$ uiso

----------------------------------------------------------------------------------------------------

It wil umount the iso file and remove the temporary directory in your home

sudo !!
2009-02-25 00:52:28
User: silbermm
Functions: sudo
-13

I often forget to type sudo before a command that needs it. This is the quickest way to rerun the command prefixed by sudo.

sudo route add xxx.xxx.xxx.xxx gw 127.0.0.1 lo
2009-02-23 19:58:09
Functions: route sudo
Tags: Security
2

Someone might attack on your system. You can drop attacker IP using IPtables. However, you can use route command to null route unwanted traffic. A null route (also called as blackhole route) is a network route or kernel routing table entry that goes nowhere. Matching packets are dropped (ignored) rather than forwarded, acting as a kind of very limited firewall. The act of using null routes is often called blackhole filtering.

sudo hdparm -Tt /dev/sda
apt-get () { [ "$1" = source ] && (command apt-get "$@";true) || sudo apt-get "$@" }
2009-02-19 04:17:24
User: mulad
Functions: apt command sudo
1

An apt-get wrapper function which will run the command via sudo, but will run it normally if you're only downloading source files.

This was a bit of an excuse to show off the framework of

cmd && echo true || echo false

...but as you can see, you must be careful about what is in the "true" block to make sure it executes without error, otherwise the "false" block will be executed.

To allow the apt-get return code to pass through, you need to use a more normal if/else block:

apt-get () { if [ "$1" = source ]; then command apt-get "$@"; else sudo apt-get "$@"; fi }
sudo dmidecode | grep Serial\ Number | head -n1
2009-02-18 14:54:28
User: nlinux
Functions: grep head sudo
14

This will give you the Dell Service tag number associated with your machine. Incredibly useful when you need that number for tech support or downloads.

sudo -l
2009-02-18 14:17:39
User: raphink
Functions: sudo
8

List the commands you have the right to use with sudo.

sudo su
2009-02-18 14:03:27
User: Vulpine
Functions: sudo
-8

Opens a new shell as root. Useful if you want to run a lot of commands as superuser without needing to sudo each of them.

echo "foo bar" | sudo tee -a /path/to/some/file
2009-02-18 13:54:25
User: raphink
Functions: echo sudo tee
3

This is the solution to the common mistake made by sudo newbies, since

sudo echo "foo bar" >> /path/to/some/file

does NOT add to the file as root.

Alternatively,

sudo echo "foo bar" > /path/to/some/file

should be replaced by

echo "foo bar" | sudo tee /path/to/some/file

And you can add a >/dev/null in the end if you're not interested in the tee stdout :

echo "foo bar" | sudo tee -a /path/to/some/file >/dev/null