Recopilación de comandos de consola Linux

file list

You can paginate results adding | pg or | less to the end.

count files in a directory

More info about symbolic files, subdirectories, etc... here.

Find files not matching a regex query

Enable the use of regex pattern list:

Use extglob to list/remove/etc the files who don't match a list of regex pattern:

Disable extglob OPTNAME:

find any file by name

space occupied by a whole directory

remove a directory including subdirectories and files inside

create symbolic link

rsync

creating/editing/assigning GROUPS of users

To compress the current directory, including all subdirectories into the archive file

To compress a directory excluding a list of files/directories:

To unzip in the current directory

recursively find the last 500 modified files, sorted by change-time

to list store drives and their available space

full emptied of the user trash (Ubuntu)

We only need install the first time:

Afterwards we use this command:

To empty System logs (because problem of space)

calculate de SHA sum of a file

copy all the content of a directory

Recursive copy of all the directories and files, even the hidden ones:

delete only files in a directory & subdirectories

change permissions of only some subdirectories

In this example we filter the subdirectories inside /path beginning with "some_" and not recursively searching inside subdirectories:

[2020-dic] easy encrypt/decrypt with symmetric key

To encrypt:

To decrypt:

In both tasks (encrypt/decrypt) the prompt will ask you for the symmetric key.

[2022-jun] reduce size of a PDF of several pages

Problem: some users upload to server a PDF containing one or more innecesary big images. Solution: to convert first each page to an optimized JPG image, and then build a new PDF file with those JPG images.

Firs we need install Poppler-utils and ImageMagick:

You probably will need modify Imagemagick security policies:

Replace this:

with this:

Finally, this will generate a JPG file for each page on the PDF:

this will join JPG pages in a new PDF:

Config the miniDLNA for read to an auto-mount partition (usually external)

Create the folder /media/sergi/hp from root user:

Create a bash file (minidlna_autostart) for mount & restart minidlna:

Execute this bash file from the autostart of the Preferences/LXSession

Edit this config file:

and set:

add a subtitle stream to an mp4 movie

FFMPEG

Convert an audio file from OGG to MP3:

Convert an audio file from MP3 to WAV:

Accelerate the speed of a movie 1.5 times, generating a new file:

Extract de audio (mp3) of a video file (flv, mp4, mkv...):

Note: use 0-10 values on -q:a 10 to control quality (more is less).

YOUTUBE-DL

Show a list of downloable formats of a same Youtube video:

Download an specific format (249):

To know the font types used in a GIMP image file (xcf)

Webcam streaming on local LAN using VLC

Command for server machine to detect video device:

It returns usually:

Begin streaming from server machine:

View video streaming on client machine (put your IP, instead):

Join multiple videos in a unique file MKV

Build a video-files.txt with the list of files to join:

Run this simple command:

How to convert MONO audio to STEREO audio from a Gnome SimpleScreenRecorder video

If the audio channel containing only SILENCE is the c0 then we use this settings to populate it with an exact copy of the audio channel c1:

enable .htaccess logging (MOD_REWRITE)

Put this line inside Directory node on a virtual host configuration file (/etc/apache2/available-sites/barllo.me.conf):

Note: 2 is the level of trace... can be from 1 to 8.

301 redirection of a whole website to a new domain

add the "official" repository

install on php7 missing pieces from php5

PHP7, solve error "Call to undefined utf8_decode()"

solution for: Call to undefined function mcrypt_decrypt()

install PDO for SQLite

install imagick & GD

Apache css/javascript cache

restart apache

vhosts in centos

cPanel MIME types for be compressed by Apache automatically

clean RAM cache

use a directory on another drive or partition using a symlink

it's not enough with create a symbolic link. The magic comes curiously when we change the execution permissions

Create a new VHOST duplicating another one

And add something like this:

To list loaded PHP.ini files location

It returns something like:

Run Apache with your user, when using ecryptfs

I needed it when i encrypted my home dir (with ecryptfs) and i put there www directory. You need to edit this file:

And replace the values of this:

And restart Apache:

empty database / delete all tables from database

download a dump of the database

make duplicated of a database from linux shell

connect

restart mysql in centos (QA server)

list of tables with a lot of columns with its properties!

disable temporally the check of integrity for foreign keys and be able to drop tables

make a dump

duplicate a table and its content

Create a new user and its privileges

List users with access to a database

Reset password to mysql root user

Stop the MySQL Server:

Start the mysqld configuration:

In some cases, you've to create the /var/run/mysqld first:

Login to MySQL as root (maybe you need to try twice !?):

Execute these mysql commands:

Note: on some versions, if password column doesn't exist, you may want to try:

work as root user

Create new user

Give root privileges to this user:

network tools

control brigthness in Lubuntu

or

or

to send output of a command though email

create/share a ssh-key

To generate a pair private/public key on your local:

To store this identification on your remote:

show network traffic monitor on console

disable Teamviewer daemon

to burn bootable ISO image to an USB drive

Easy command for make a bootable USB from an ISO file:

set spanish keyboard

disable touchscreen on startup

You must add this command to the startup app list:

To migrate IMAP messages

Very useful command for pass ALL the email messages & folders from a server to other, usually during a server migration:

Note 1: add --dry --justfolders to check (without changes) the correct mapping of the folders.

Note 2: so, usually one of the hosts is an IP (note: the IP of the mail server USUALLY is not the same of the web server IP!). Sometimes the recommendation is not to set port neither ssl/tls settings. The imapsync script is enough smart to test some typical connection settings by himself if you don't specify those settings.

Clone a remote directory using FTP

To make a perfect recursively clone of a remote directory, including hidden files/directories:

To generate a private/public key pair

To upload a SSH key to login on server

To kill teamviewer process and avoid future auto-boot

To avoid future autoboot execution:

To "kill" process (to stop daemon):

Basic tasks with CRONTAB

To edit crontab file for current user:

To add a new crontab file to a user:

To check the last executions of ALL crontabs:

Upload a local file to server using SSH

You must run a command like this from your local terminal

Download a remote file to local using SSH

You must run a command like this from your local terminal

If you get an error related to permission denied, try this:

Anyway, you must be sure than the user remoteuser has read permission over that file on server.

If any of the paths contain spaces, use this:

[2020] Increase font size on terminal

On terminal run this command to edit console setup:

Once inside, change the font size:

[2020] Disable some hardware on boot (touchscreen, built-in webcam...)

Using this command i found that my webcam (which use driver uvcvideo) is on the Bus X and Device Y:

And in the output of this other command i find that the vendorID and productID of the device and those Bus X & Device Y is something like 0bda:573d:

So now i add this new rule (file):

and i put inside this:

[2020] Send email from terminal with subject and body

Whenever we have installed and configured an email server like exim, usually on an VM. Thern we can do it with a single terminal command line, breaking lines with \n. It's necessary to delimiter string content with single quote, not double quote:

[2020-nov] Useful network/wifi CLI-tools

Info about all netowrk interfaces (IP, type,...):

Graphical list of all wifi access points and their quality

Graphical list of all wifi access points and their quality

[2020-dic] Migrate a whole server between two VM's using scp/ssh

Use the next command when you need to "move" all your server (settings, databases, mail... almost all) from a VPS to another one. You must have installed the same OS version on both machines. From the terminal connected to the origin machine run this:

[2021-feb] Get details of a PID process

[2021-sep] Deactivate/activate a built-in wifi device

To know the name of the network device to be deactivated:

To deactivate the use of a device:

To re-activate it:

[2022-apr] Run an installed flatpak app

With this command you get the list of installed flatpak apps and its "name":

[2022-mai] Customize keyboard map layout on X11 to add foreign symbols

In this example i want to render "ç" when pressing ALTGR+c in a latam keyboard:

There you must edit this line, putting "ccedilla" instead of "cent" and "copyright":

And then reload keyboard layout with:

[2022-oct] Useful keyboard shortcuts on GNOME

Open capture GUI of flameshot (installed via Flatpak):

Temporally suspend ubuntu:

[2023-mar] Start SSH server on boot

To check the status: