Linux
#####

Usefull Programms (Nice To Have)
================================
* Wireshark (Network analysing tool)
* HexChat (IRC-Chat with filetransfering capabilities)
* irssi (IRC-Clinet CLI)
* IntelliJ (IDE)
* MySQL Workbench
* krita (raster graphics editor)
* shotcut (video editing)
* dc or bc (CLI-Calculator)
* lynx (CLI-Browser without Graphics)

Watch Star Wars over IPv6
=========================
.. code-block:: bash

   telnet 2001:980:ffe:1::42


Check Memory usage
==================
.. code-block:: bash

   smem -t -P firefox


Check Occupied Storage Space
============================
Whole Disk
**********

.. code-block:: bash

   df -h

In Folder
*********
.. code-block:: bash

   du -h | sort -h -r

Over whole Filesystem (fast)
****************************
.. code-block:: bash

   ncdu

Check how many files are in subfolders
======================================
.. code-block:: bash

   find . -type f -printf '%h\n' | cut -d/ -f2 | sort | uniq -c | sort -n
   -maxdepth 2 # Can be added to only list files in direct subfolder, instead of recursive files in all folders


Show Hardware Info
==================
.. code-block:: bash

   sudo lshw -short

Monitor CPU-Clock Speed
=======================
.. code-block:: bash

   watch -n1 "cat /proc/cpuinfo | grep "^[c]pu MHz""

Find out OS Version
===================
.. code-block:: bash

   cat /etc/*-release
   lsb_release -a

Find out Processor Architecture
===============================
.. code-block:: bash

   lscpu

Find out NIC-Speed
==================
.. code-block:: bash

   sudo ethtool eth0 | grep Speed

Find out MAC-Addresses of Network Devices
=========================================
.. code-block:: bash

   ping <IP-Address of Target>
   arp -a

   ping -I eth0 fe80::...:

Create Password in Shell
========================
.. code-block:: bash

   date +%s | sha256sum | base64 | head -c 32 ; echo

Interact with date in CLI
=========================
.. code-block:: bash

   $(date "%d-%m-%Y_%H-%M-*" -d "-20 minutes")
   $(date "%d-%m-%Y_%H-%M-%S" -d "-20 minutes")


Distributed Computing
=====================
BOINC
*****

Setup:

.. code-block:: bash

   cd /var/lib/boinc-client
   boinccmd --project_attach https://milkyway.cs.rpi.edu/milkyway/ <secret_key>
   boinccmd --project_attach https://einsteinathome.org/ <secret_key>
   boinccmd --project_attach https://setiathome.berkeley.edu/ <secret_key>
   boinccmd --project_attach https://boinc.bakerlab.org/rosetta/ <secret_key>
   boinccmd --get_state

Disallow more Work:

.. code-block:: bash

   boinccmd --project https://milkyway.cs.rpi.edu/milkyway/ nomorework
   boinccmd --project https://einsteinathome.org/ nomorework
   boinccmd --project https://setiathome.berkeley.edu/ nomorework
   boinccmd --project https://boinc.bakerlab.org/rosetta/ nomorework

Allow more Work:

.. code-block:: bash

   boinccmd --project https://milkyway.cs.rpi.edu/milkyway/ allowmorework
   boinccmd --project https://einsteinathome.org/ allowmorework
   boinccmd --project https://setiathome.berkeley.edu/ allowmorework
   boinccmd --project https://boinc.bakerlab.org/rosetta/ allowmorework

Abort specific Task:

.. code-block:: bash

   --task URL task_name abort

FAH (Folding at Home)
*********************
.. code-block:: bash

   --user=<user_name> --team=<team_id> --passkey=<secret_key> --gpu=false --smp=true

Record Streams/Mediathek aufnehmen
==================================

ARD
***
.. code-block:: bash

   ffmpeg -i "https://dasersteuni-vh.akamaihd.net/i/int/2018/11/16/2ee8249b-c8f0-4a25-b8ac-260bd7caba5a/,640-3,512-3,1280-3,320-3,960-3,480-3,.mp4.csmil/index_2_av.m3u8?null=0" -bsf:a aac_adtstoasc -c copy "tatortTreibjagd.mp4"

ZDF
***
.. code-block:: bash

   ffmpeg -i "http://zdfvoddach-vh.akamaihd.net/i/meta-files/3sat/smil/m3u8/300/18/11/181119_weit_film/3/181119_weit_film.smil/master.m3u8" -c copy "video.mp4"

Funk.net
********
.. code-block:: bash

   ffmpeg -i https://funk-02.akamaized.net/22679/files/21/06/11/3409640/22679-vhDVH6jMpQC2Yf3.ism/manifest.mpd -codec copy out.mp4


Twitch Recording
================
Required:

* vlc
* streamlink

.. code-block:: bash

   streamlink https://www.twitch.tv/rocketbeanstv best

or

.. code-block:: bash

   streamlink --output /home/<user>/Videos/twitchCapture.mp4 https://www.twitch.tv/rocketbeanstv best

   streamlink --output /home/<user>/Videos/youtubeCapture.mp4 https://www.youtube.com/watch?v=p3n0wLkXpoI best

.. note::
   Bei YouTube Downloads muss `*--demux=ffmpeg*` bei der wiedergabe mit vlc gesetzt werden.


Audio editing
=============
split cue file
**************
.. code-block:: bash

   sudo apt install shntool cuetools flac wavpack

.. code-block:: bash

   shntool split -f *.cue -o flac -t '%n - %p - %t' *.ape shntool split -f *.cue -o flac -t '%n - %p - %t' *.flac

or

.. code-block:: bash

   shntool split -f <cue-File>.cue -o flac -t '%n - %p - %t' <flac-File>.flac

flac to mp3
***********
.. code-block:: bash

   ffmpeg -i title.flac -qscale:a 0 title.mp3

   for f in *.flac; do ffmpeg -i "$f" "mp3/${f%.flac}.mp3" ; done


mkv to mp3
**********
.. code-block:: bash

   ffmpeg -i *.mkv -b:a 320K -vn title.mp3

Mappings for "page up" and "page down" to search in history
===========================================================

.. code-block:: bash

   sudo vi /etc/inputrc

   "e[5": history-search-backward
   "e[6": history-search-forward

.. note::
   To take immediate Effect run: `exec bash -l`

rdesktop
========
.. code-block:: bash

   rdesktop -u <user> <IP/NameOfServer> -g 1920x1040 -r clipboard:[off|PRIMARYCLIPBOARD|CLIPBOARD]


Hide Data in Images
===================
* http://domnit.org/blog/2007/02/stepic.html

Change Color of PDF-Text for semi-working printers... ;)
========================================================
.. code-block:: bash

   convert -density 300 test.pdf -fuzz 10% -fill blue -opaque black result.pdf

Shred Drive/HDD
===============
.. code-block:: bash

   shred -vfz -n 5 /dev/sdX

Check S.M.A.R.T-Info
====================
.. note::
   Install with `sudo apt install smartmontools`

.. code-block:: bash

   sudo smartctl -a /dev/sdb

Search for file
===============

.. code-block:: bash

   find . -name *foo*

or

.. code-block:: bash

   sudo apt install mlocate
   sudo updatedb
   locate <search_string> (Case Sensitive)
   locate -i <search_string> (Case Insensitive)


Search inside file
==================

.. code-block:: bash

   grep -nHo "search" * # Display filename and line-number


Rip Movies
==========
* http://www.videolan.org/developers/libdvdcss.html
* Release downloaden und als sudo config und make ausführen (Siehe INSTALL) Handbreak (per apt installieren) Mit Handbreak DVD rippen (selbserklärend)

Sokoban
=======
* Next Level to play: 16
* dosbox (Alt   Return = Fullscreen)
* mount c ./Downloads/Sokoban
* c:
* skb.exe
* U = Undo, L = Leave, P = Pause Remapping the keyboard and joystick

When you start the mapper (either with CTRL-F1 or -startmapper as a commandline argument to the DOSBox executable)

vim
===
* save file: ':w'
* quit editing: ':q'
* search for pattern: '/<pattern>'
* search for a pattern without case: '/c<stringToSearch>'
* repeat search in same direction: 'n'
* repeat search in oposite direction: 'N'
* replace 'old' with 'new' ':%s/old/new/g'
* ':%s/ //g'


Create Bootable USB-Stick
=========================

.. code-block:: bash

   sudo dd if=<ISO-File> of=/dev/sdX status=progress


Mount Drive on Boot
===================

Hard-Drive
**********

Get the blockid with :code:`blkid`

Edit :file:`/etc/fstab` and insert the follwing:

.. code-block:: bash

   UUID=<uid-got-from-blkid> <path-to-mount> <filesystemtype (auto,ntfs,ext4)> rw,user,auto,errors=continue 0 0

Test with :code:`sudo mount -a`


Samba-Share
***********
Public-Share:

.. code-block:: bash

   //<ip>/public /media/<mount-path> cifs vers=3.0,password= 0 0


sshfs
*****
.. note::
   If no SSH-Key exists, run `ssh-keygen -o -a 100 -t ed25519 -f ~/.ssh/id_ed25519 -C "<comment for this key>"` followed by `cat .ssh/id_rsa.pub | ssh <user>@<domain/ip> 'cat >> .ssh/authorized_keys'`

To test mounting the remote drive:

.. code-block:: bash

   sudo sshfs -o IdentityFile=/home/tidoni/.ssh/id_rsa,allow_other,default_permissions <user>@<domain/ip>:/media/Data/ /mnt/NeoPI/

Set in /etc/fstab

.. code-block:: bash

   sshfs#<user>@<domain/ip>:/media/Data/ /mnt/NeoPI/ fuse default_permissions,allow_other,IdentityFile=/home/tidoni/.ssh/id_rsa 0 0

.. hint:: to test the inserted mount command run `mount -a`

Execute Command for multiple files
==================================
.. code-block:: bash

   for f in *; do cp "$f" "foo/$f" ; done

Rename all files in folder
==========================
.. code-block:: bash

   for file in *; do mv "$file" `echo $file | sed 's/ /./g'` ; done

pdftk
=====
Split a PDF file:

.. code-block:: bash

   pdftk fileToSplit.pdf burst

or
.. code-block:: bash

   pdftk source.pdf burst output source-%d.pdf

Merge multiple PDF files:

.. code-block:: bash

   pdftk firstFile.pdf secondFile.pdf thirdFile.pdf ... output mergedFile.pdf

.. hint:: Use \*.pdf to merge all PDF-Files in the current Folder

To rotate some pages 'within' a pdf, you can use:

.. code-block:: bash

   pdftk in.pdf cat 1-10 11right 12-16 17-18right 19-23 24-26right 27-end output out.pdf

.. hint:: possible options are right, left, down or west, east, south.


Console shortcuts
=================
Resize or Move Consol with :kbd:`Alt` + :kbd:`F5-F8`

Networking
==========

Find devices in Subnet
**********************
.. code-block:: bash

   nmap -sP <ip_Address>/<size_of_Subnet>

.. code-block:: bash

   nmap -sP 192.168.178.0/24

.. code-block:: bash

   nmap -p- <domain>

Showing local (open)Ports
*************************
.. code-block:: bash

   nmap -sT -O localhost


RSYNC
*****
.. code-block:: bash

   rsync -av -r -e 'ssh -p <port>' <local_Folder> <user>@<remote_Domain_or_IP>:<remote_Path>

Autostart programm on startup
=============================
Insert command into /etc/rc.local

.. code-block:: bash

   sudo vim /etc/rc.local

Show running processes atteched to terminal
*******************************************
.. code-block:: bash

   jobs
   ps

Data rescue/recovery
********************
* Create 1 to 1 image of drive:

.. code-block:: bash

   dd if=<device to be imaged/copied> of=<where to put image>

If the drive is having physical problems:

.. code-block:: bash

   ddrescue <device to be imaged/copied> </example/path/rescue.img> </example/path/rescue.map>


From https://www.gnu.org/software/ddrescue/manual/ddrescue_manual.html:

.. code-block:: bash
   
   -r n

   --retry-passes=n

Exit after the given number of retry passes. Defaults to :code:`0`. :code:`-1` means infinity.
Every bad sector is tried only once in each pass. The direction is reversed after each pass.
To retry bad sectors detected on a previous run, you must specify a non-zero number of retry passes.
A command like :code:`ddrescue -f -r-1 /dev/sdcard /dev/null mapfile` can be used to read repeatedly until the device controller succeeds and remaps the bad sectors internally. 


.. hint:: <device to be imaged> could be :code:`/dev/sdf` for usb stick or :code:`/dev/sda` for first hard drive <where to put image> :code:`./*someFolder*/recover.image`

* Try to extract files from image/partition

.. code-block:: bash

   photorec [/log] [/debug] [/d recup_dir] [device|image.dd|image.e01]


Photo conversion
================
Tiff in jpg
***********
Move to folder containing tif images, create jpg folder if not exist (mkdir jpg)

.. code-block:: bash

   for f in *.tif;
   do
      echo "Converting $f";
      convert "$f" "jpg/$(basename "$f" .tif).jpg";
   done


Manjaro setup xrp
=================
.. code-block:: bash

   yay -S xrdp

OBS Camera streaming
====================
.. code-block:: bash

   sudo modprobe v4l2loopback
   sudo obs

Tools → v4l2sink /dev/video2 YUV420 starten


CLI View Network Traffic (Slurm)
================================
.. code-block:: bash

   slurm -z -s -d 1 -i <Your-Network-Interface>


Refresh time from ntp
=====================
.. code-block:: bash

   sudo ntpdate pool.ntp.org

Setting to sync time automatically

.. code-block:: bash

   timedatectl set-ntp yes


Create Samba-Share (public)
===========================
.. code-block:: bash

   sudo vim /etc/samba/smb.conf

.. code-block:: bash

   [global]
   netbios name = linuxserver
   workgroup = WORKGROUP
   server string = Public File Server

   [transfer]
   path = /srv/transfer
   writeable = yes
   browseable = yes
   public = yes
   create mask = 0644
   directory mask = 0755
   force user = shareuser

.. code-block:: bash

   sudo useradd --system shareuser
   sudo groupadd sharegroup
   sudo useradd shareuser -G sharegroup

   sudo chown -R shareuser:shareuser /srv/storage/

Make it accesible from Windows machines

.. code-block:: bash

   sudo vim /etc/samba/smb.conf

.. code-block:: bash

   [public]
 	 comment = Public Shares
 	 browsable = yes
 	 path = /data/pub
 	 public = yes
 	 writable = yes
 	 write list = nobody
 	 guest ok = yes
 	 create mask = 0644
 	 directory mask = 2777

.. code-block:: bash

   sudo mkdir /data
   sudo mkdir /data/pub
   sudo chmod -R 777 /data/
   sudo smbpasswd -an nobody



Create NFS (Network File System)
================================

Install on Host:

.. code-block:: bash

   sudo apt install nfs-kernel-server


.. code-block:: bash

   sudo mkdir /<path>/<to>/<dir> -p
   sudo chown nobody:nogroup /<path>/<to>/<dir>


.. code-block:: bash

   sudo vim /etc/exports


.. code-block:: bash

   /<path>/<to>/<dir>    <ip-address_of_receiver>(rw,sync,no_subtree_check)

.. code-block:: bash

   sudo systemctl restart nfs-kernel-server
   sudo systemctl enable nfs-kernel-server

   
To Mount Drive on IRC-Client
****************************

Install on Client:

.. code-block:: bash

   sudo apt install nfs-common

.. code-block:: bash

   sudo mount <ip-address_of_host>:/<path>/<to>/<dir> /<path>/<where>/<to>/<mount>

/etc/fstab
**********
.. code-block:: bash

   <ip-address_of_host>:/<path>/<to>/<dir>    /<path>/<where>/<to>/<mount>   nfs auto,nofail,noatime,nolock,intr,tcp,actimeo=1800 0 0



Libs (Updates the necessary links for the run time link bindings)
=================================================================
.. code-block:: bash

   sudo ldconfig


Run command for sequence (1...10)
=================================

.. code-block:: bash

   for i in $(seq 1 10);
   do
      echo $i
   done


Use Laptop as server
====================
Do nothing on lit closed
For 13.10 - 21.10:

To disable Ubuntu doing anything closing the laptop lid:

Open the :file:`/etc/systemd/logind.conf` file in a text editor as root, for example,


If HandleLidSwitch is not set to ignore then change it:

.. code-block:: bash

   HandleLidSwitch=ignore

Make sure it's not commented out (it is commented out if it is preceded by the symbol #) or add it if it is missing.

Restart the systemd daemon (be aware that this will log you off) with this command:

.. code-block:: bash

   sudo systemctl restart systemd-logind

or, from 15.04 onwards:

.. code-block:: bash

   sudo service systemd-logind restart


Setup SWAP on Linux
===================

.. code-block:: bash

   swapon --show
   free -h

   sudo fallocate -l 8G /swapfile
   sudo chmod 600 /swapfile
   sudo mkswap /swapfile

   sudo swapon /swapfile
   swapon --show

Make SWAP permanent in fstab
****************************

.. code-block:: bash

   sudo cp /etc/fstab /etc/fstab.back


Edit :file:`/etc/fstab` and add

.. code-block:: bash

   /swapfile none swap sw 0 0

or run 

.. code-block:: bash

   echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab


Adjust swappiness
*****************

The swappiness parameters specifies how often the swap space is beeing used.
The value can be between 0 and 100. Higher value means the swap space will be used more often.

The default swappiness in Desktop PCs is 60 (Ubuntu) while in server it is 1.

You can check the swappiness with the following command:

.. code-block:: bash

   cat /proc/sys/vm/swappiness

Because swap is slower than RAM, in servers this value is small, so the RAM gets used as much as possible, befor falling back to swap.

You can change the swappiness on a live system with the following command:

.. code-block:: bash

   sudo sysctl vm.swappiness=25

To make the change permanent, change the :file:`/etc/sysctl.conf` and add the swappiness value to the end of the file:

.. code-block:: bash

   vm.swappiness=25



Setup a second Network(card)
============================

Check Hardware and current configuration

.. code-block:: bash

   ip a
   sudo lshw -class network

Create a new file under :file:`/etc/netplan/...` with the settings for the new network.



.. code-block:: bash

  network:
    ethernets:
      <device-name>:
        addresses:
        - <ip-address>/<subnet>
        gateway4: <gateway-ip-address>
        nameservers:
          addresses:
          - <dns1-ip-address>
          - <dns2-ip-address>
          search:
          - <search-domain>
     version: 2

Test config by running

.. code-block:: bash

   sudo netplan apply


The second network may not have a gateway or dns-servers, depending on the particular setup.


Show Network/DNS Settings
=========================
.. code-block:: bash

   nmcli dev show



Send Mail using Relay-Host
==========================

edit :file:`/etc/postfix/main.cf`
insert :code:`relayhost = <your_mail_host>`
restart postfix :code:`/etc/init.d/postfix force-reload`

In a Windows Mail Environment goto exchange controll panel (https://<your_exchange_server>/ecp/); there go to Nachrichtenfluss -> empfangsconnectors and add your server to the noAuthenticate Groupe.




Kali
====

Find WiFi-Key
*************
.. code-block:: bash

   sudo wifite --kill
   sudo wifite --kill --dict <wordlist.txt> --no-wps --no-pmkid


Find key of ZIP
***************
.. code-block:: bash

   zip2john <zipFile> > <writeHere.hash>
   john <writeHere.hash> --wordlist=<wordlist.txt>


Scan Wordpress installation for a vulnerability
***********************************************
.. code-block:: bash

   wpscan






Vergrößern der VM LVM Festplatte OHNE NEUSTART 
==============================================
.. code-block:: bash

   sudo cfdisk
   
   sudo growpart /dev/sda 3 # (Schau erst welche Partition vergrößert werden soll, hier SDA3)

   sudo lvmdiskscan
   sudo lvextend -l+100%FREE /dev/ubuntu-vg/ubuntu-lv
   sudo resize2fs /dev/mapper/ubuntu--vg-ubuntu--lv



Fedora
======

Update/Upgrade
**************

.. code-block:: bash

   sudo dnf upgrade --refresh
   sudo dnf system-upgrade download --releasever=<relese-version (39/40/41)>
   sudo dnf system-upgrade reboot