Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. 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.


If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Hide

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:

Hide

News

2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.
Hide

Tags

Hide

Functions

Commands tagged backup from sorted by
Terminal - Commands tagged backup - 55 results
tar --exclude-from=$excludefile -zcvp "$source" | openssl aes-128-cbc -salt -out $targetfile -k $key
2013-12-13 19:35:20
User: klausman
Functions: tar
0

Create compressed, encrypted backup from $source to $targetfile with password $key and exclude-file $excludefile

sudo tar -zcvf $(hostname)-etc-back-`date +%d`-`date +%m`-`date +%y`.tar.gz /etc && sudo chown $USER:$USER $(hostname)-etc-back*
2013-08-18 12:49:11
User: thanosme
Functions: chown sudo tar
Tags: backup tar date
0

Back up /etc directory with a name based on the current date and the hostname of the machine, then chown the file for the current user for use.

find /var/scripts -name 'backup*' -exec {} ';'
2013-07-24 21:25:21
User: piscue
Functions: find
Tags: backup
0

It eases the way of creating cron jobs of backup scripts.

Just put this line as cron job, and all your backups are called sequentially.

Allows you to forget, when in time, call this backup, just focus on your scripting. Also maintains the way of calling a single backup script when It's needed.

find . | sort | awk 'NR%2==0' | xargs rm $1
2013-07-11 07:36:18
User: sucotronic
Functions: awk find rm sort xargs
-1

If you have a directory with lot of backups (full backups I mean), when it gets to some size, you could want to empty some space. With this command you'll remove half of the files. The command assumes that your backup files starts with YYYYMMDD or that they go some alphabetical order.

rsync -avzhP <[[user@]host1:]directory1> <[[user@]host2:]directory2>
gzip -c ~/.bash_history > ~/.backup/history-save-$(date +\%d-\%m-\%y-\%T).gz
2013-01-11 17:31:07
User: tictacbum
Functions: date gzip
Tags: history backup
0

this one works on user crontab

buf () { oldname=$1; if [ "$oldname" != "" ]; then datepart="$(date +%Y-%m-%d).bak"; firstpart=`echo $oldname | cut -d "." -f 1`; newname=`echo $oldname | sed s/$firstpart/$firstpart.$datepart/`; cp -iv ${oldname} ${newname}; fi }
2012-08-15 08:31:44
User: juliushibert
Functions: cp cut sed
1

Appends the input file with the date format YYYY-MM-DD.bak. Also runs silently if you remove the -v on the cp at the end of the function.

dvdisaster -vr --defective-dump . --internal-rereads 5 --raw-mode 20 --read-attempts 1-23 --read-raw --speed-warning 12 --adaptive-read --auto-suffix --read-medium 2 && dvdisaster -vc -mRS02 --raw-mode 20 --read-raw --auto-suffix
tar zcpvf backup.tgz $(find $HOME -maxdepth 1 -name '.*' -and -not -name '.')
2012-05-01 17:48:24
User: DavidAlfonso
Functions: find tar
Tags: backup
0

This will make a backup of all hidden files and folders in the home folder.

cp -auv /SorceDirectory/ /ParentDestination/
2012-03-04 13:04:03
User: joeseggiola
Functions: cp
1

Backup a whole directory copying only updated files.

find /protocollo/paflow -type f -mtime +5 | xargs tar -cvf /var/dump-protocollo/`date '+%d%m%Y'_archive.tar`
2012-02-03 16:24:08
User: 0disse0
Functions: find tar xargs
1

Finally, we can make the file "unchangeable"

sudo chattr +i

curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-9000:25] | grep -vE "_curl_|\.com by David" > clf-ALL.txt
2011-11-08 12:19:48
User: totti
Functions: grep
2

Faster then other method using wget

For obtain all commands use

nu=`curl http://www.commandlinefu.com/commands/browse |grep -o "Terminal - All commands -.*results$" | grep -oE "[[:digit:],]{4,}" | sed 's/,//'`; curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-"$nu":25] | grep -vE "_curl_|\.com by David" > clf-ALL.txt

For more version specific

nu=`curl http://www.commandlinefu.com/commands/browse |grep -o "Terminal - All commands -.*results$" | grep -oE "[[:digit:],]{4,}" | sed 's/,//'`; curl http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/[0-"$nu":25] | grep -vE "_curl_|\.com by David" > clf-ALL_"$nu".txt

Also download dirctly from my dropbox

My drop box invitaion link is http://db.tt/sRdJWvQq . Use it and get free 2.5 GB space.

rsync --daemon --port 9999 --no-detach -v --config .rsyncd.conf
2011-09-22 20:48:31
User: pykler
Functions: rsync
-3

An example config file is placed in the sample output along with the command line call to use it.

The rsync daemon here is setup on the destination, thus requiring the read only = false flag. Also it uses uid and gid of root, change as required.

mv -b old_file_name new_and_already_existent_file_name
2011-09-08 23:57:15
User: ztank1013
Functions: mv
Tags: backup mv cp safe
5

Sometimes in a hurry you may move or copy a file using an already existent file name. If you aliased the cp and mv command with the -i option you are prompted for a confirmation before overwriting but if your aliases aren't there you will loose the target file!

The -b option will force the mv command to check if the destination file already exists and if it is already there a backup copy with an ending ~ is created.

mount /dev/root /mnt/root; rsync -avHX /mnt/root/ /mnt/target/
2011-08-24 14:29:17
User: jharr
Functions: mount rsync
1

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.

rsync -aHux --exclude=/proc/* --exclude=/sys/* /* /mnt/target/
2011-08-22 14:26:56
Functions: rsync
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.

cp -dpRx /* /mnt/target/
2011-08-22 14:22:01
Functions: cp
-1

preserve all except context and xattr. useful when moving a running system to a new partition.

cp httpd.conf{,.bk}
2011-08-15 16:43:53
User: ideivid
Functions: cp
Tags: backup cp
17

Remember to backup everything before changing it so you can restore all to normal.

tar jcpf /home/[usuario]/etc-$(hostname)-backup-$(date +%Y%m%d-%H%M%S).tar.bz2 /etc
2011-04-29 22:53:11
User: mack
Functions: date tar
-1

Simple Compressed Backup of the /etc

Linux compatible

cp filename{,.`date +%Y%m%d`}
2011-04-02 06:41:26
Functions: cp
Tags: backup copy
4

This is a BASH feature.

The above command will create a backup of "filename" called "filename.DATE", where DATE is the actual day in %Y%m%d (year, month and day numbers together) format.

buf() { cp -v $1 ${1/${1%%.*}/$f-$(date +"%Y%m%d_%H%M%S")};}
buf() { f=${1%%.*};e=${1/$f/};cp -v $1 $f-$(date +"%Y%m%d_%H%M%S")$e;}
2010-12-15 09:50:04
User: unefunge
Functions: cp date
0

"infix" version in bash (4.x+)

Remove -v to make it silent.

BTW: The OP forgot to use "cat" and "nmap" ;-) I had a good laugh though.

buf () {oldname=$1; if [ "$oldname" != "" ]; then datepart=$(date +%Y-%m-%d); firstpart=`echo $oldname | cut -d "." -f 1`; newname=`echo $oldname | sed s/$firstpart/$firstpart.$datepart/`; cp -i ${oldname} ${newname}; fi }
2010-12-14 19:58:34
User: Seebi
Functions: cp cut date sed
-3

This backup function preserve the file suffix allowing zsh suffix aliases and desktop default actions to work with the backup file too.

buf () { cp $1{,$(date +%Y%m%d_%H%M%S)}; }
2010-12-14 14:02:03
User: unefunge
Functions: cp date
2

1. you don't need to prepend the year with 20 - just use Y instead of y

2. you may want to make your function a bit more secure:

buf () { cp ${1?filename not specified}{,$(date +%Y%m%d_%H%M%S)}; }

alias tarred='( ( D=`builtin pwd`; F=$(date +$HOME/`sed "s,[/ ],#,g" <<< ${D/${HOME}/}`#-%F.tgz); tar --ignore-failed-read --transform "s,^${D%/*},`date +${D%/*}.%F`,S" -czPf "$F" "$D" &>/dev/null ) & )'
2010-11-18 06:24:34
User: AskApache
Functions: alias date tar
7

This is freaking sweet!!! Here is the full alias, (I didn't want to cause display problems on commandlinefu.com's homepage):

alias tarred='( ( D=`builtin pwd`; F=$(date +$HOME/`sed "s,[/ ],#,g" <<< ${D/${HOME}/}`#-%F.tgz); S=$SECONDS; tar --ignore-failed-read --transform "s,^${D%/*},`date +${D%/*}.%F`,S" -czPf "$"F "$D" && logger -s "Tarred $D to $F in $(($SECONDS-$S)) seconds" ) & )'

Creates a .tgz archive of whatever directory it is run from, in the background, detached from current shell so if you logout it will still complete. Also, you can run this as many times as you want, if the archive .tgz already exists, it just moves it to a numbered backup '--backup=numbered'. The coolest part of this is the transformation performed by tar and sed so that the archive file names are automatically created, and when you extract the archive file it is completely safe thanks to the transform command.

If you archive lets say /home/tombdigger/new-stuff-to-backup/ it will create the archive /home/#home#tombdigger#new-stuff-to-backup#-2010-11-18.tgz Then when you extract it, like tar -xvzf #home#tombdigger#new-stuff-to-backup#-2010-11-18.tgz instead of overwriting an existing /home/tombdigger/new-stuff-to-backup/ directory, it will extract to /home/tombdigger/new-stuff-to-backup.2010-11-18/

Basically, the tar archive filename is the PWD with all '/' replaced with '#', and the date is appended to the name so that multiple archives are easily managed. This example saves all archives to your $HOME/archive-name.tgz, but I have a $BKDIR variable with my backup location for each shell user, so I just replaced HOME with BKDIR in the alias.

So when I ran this in /opt/askapache/SOURCE/lockfile-progs-0.1.11/ the archive was created at /askapache-bk/#opt#askapache#SOURCE#lockfile-progs-0.1.11#-2010-11-18.tgz

Upon completion, uses the universal logger tool to output its completion to syslog and stderr (printed to your terminal), just remove that part if you don't want it, or just remove the '-s ' option from logger to keep the logs only in syslog and not on your terminal.

Here's how my syslog server recorded this..

2010-11-18T00:44:13-05:00 gravedigger.askapache.com (127.0.0.5) [user] [notice] (logger:) Tarred /opt/askapache/SOURCE/lockfile-progs-0.1.11 to /askapache-bk/tarred/#opt#SOURCE#lockfile-progs-0.1.11#-2010-11-18.tgz in 4 seconds

Caveats

Really this is very robust and foolproof, the only issues I ever have with it (I've been using this for years on my web servers) is if you run it in a directory and then a file changes in that directory, you get a warning message and your archive might have a problem for the changed file. This happens when running this in a logs directory, a temp dir, etc.. That's the only issue I've ever had, really nothing more than a heads up.

Advanced:

This is a simple alias, and very useful as it works on basically every linux box with semi-current tar and GNU coreutils, bash, and sed.. But if you want to customize it or pass parameters (like a dir to backup instead of pwd), check out this function I use.. this is what I created the alias from BTW, replacing my aa_status function with logger, and adding $SECONDS runtime instead of using tar's --totals

function tarred ()

{

local GZIP='--fast' PWD=${1:-`pwd`} F=$(date +${BKDIR}/%m-%d-%g-%H%M-`sed -u 's/[\/\ ]/#/g'

[[ ! -r "$PWD" ]] && echo "Bad permissions for $PWD" 1>&2 && return 2;

( ( tar --totals --ignore-failed-read --transform "s@^${PWD%/*}@`date +${PWD%/*}.%m-%d-%g`@S" -czPf $F $PWD && aa_status "Completed Tarp of $PWD to $F" ) & )

}

#From my .bash_profile http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html