Netstat is a tool that we can use through the command line. It allows us to monitor networks and also to troubleshoot certain problems that may arise. Also, it is widely used to identify the TCP connections that are active on the machine on which the command is executed.

All this, we emit an output screen where we can visualize the network information or even export it through the use of commands.

This tool is quite useful for the more technical Linux users because it allows us to quickly analyze and detect possible problems that are happening in our network. Even more, to make an analysis on it.

Despite being so popular, it is not included in most Linux distributions and that is why in this post, we will help you how to install it.

So, let’s start.

Install the Netstat on Linux command

As we said, being such a popular tool, it is hard to believe that it is not included in the existing Linux distributions.

The solution to this is to install via official repositories, the net-tools package in order to add the command but also other important tools.

So, in the case of Debian, Ubuntu, Linux Mint, ElementaryOS, and any distribution based on any of these, just open the terminal and execute

sudo apt update
sudo apt install net-tools

In case you are using, Fedora 34, RockyLinux, AlmaLinux OS, RHEL 8, CentOS 8, Oracle Linux 8, or any distribution based on these.

sudo dnf install net-tools

But, if you are using older versions such as RHEL 7, CentOS 7, Oracle Linux 7, or any of their derivatives, then you will need to run

sudo yum install net-tools

A very popular distribution among Linux users is Arch Linux. It also has some derivatives such as Manjaro. For these distributions or any derivative of them, just run:

sudo pacman -S netstat-nat

As we all know, one of our favorite distributions is OpenSUSE, so we can’t leave it out.

So, to install it on OpenSUSE

sudo zypper in net-tools

This way we will be able to use it from the terminal without problems.

Using the Netstat command

It is normal to use the command directly on the terminal. And there it will show much of the default information of the active network interface.

Another common use is to run it together with some other options, for example:

netstat -tulpn

For more complex use of this command, we have prepared a post on the use of Netstat where you can find use cases.

Monitor Network with netstat command in Linux

So, enjoy it.

Conclusion

These types of commands can be useful in our work where many tools are required to help with network control. Although there are more specialized and larger tools, it is also true that sometimes we just need a little help.

The post How to install the netstat command on Linux? appeared first on Linux Windows and android Tutorials.

I think you already know but there are commands to create a user, delete a user, list registered users, but at work needs always arise. And if you need to know which are the users of the system? What is that command?

Well, there are several commands, and each one has its own way of doing the job and you can even combine them to get better results.

Let’s go for it.

How to list users in Linux

Commands that use the /etc/passwd file

In the /etc/passwd file you can find information about the system users. However, it is not as readable as you would like it to be, it is a good option.

Open a terminal and run the following command

cat /etc/passwd

And you will get a screen output similar to this.

The first thing you may notice is that there are many users but most of them are system users required to perform many operations that have to do with the operation of the system.

The second thing is that the information is separated by columns where different fields are shown such as Username, encrypted password, UID, GID, and other information.

If you want to know only the users, you can filter the on-screen output of the cat command with the help of the cut command.

cat /etc/passwd | cut -d: -f1

This way only the users will be displayed without the rest of the information.

The same result can be obtained with the command awk.

cat /etc/passwd | awk -F: '{print $1}'

This way we will be able to list the system users.

List users in Linux with compgen

Although the above commands are easy to use, they are not so easy to memorize. Especially when you have to share them with others.

That is why there is the command compgen with which we can simply get all the users of the system.

To do this, just run

compgen -u

And in this simple way, we will be able to have all the users of the system.

Bonus: List the users connected to the system

On the other hand, it is convenient on many occasions to know which are the users that are connected in real-time with the system. To do this you only have to run

who

And you will be able to list the users that are using the system at this moment.

Conclusion

A terminal is a tool in which many professionals make their working life and that is full of tricks to take full advantage of it. In this post, you have learned how to list users in Linux quickly and easily.

The post How to List users in Linux? appeared first on Linux Windows and android Tutorials.

The find command is a command that searches for files and folders, from the command line, in a directory tree. It is used by many users who work in the terminal and can help even the most veteran users of the system.

So, let’s show you some examples of how to use the command to find files in any Linux distribution.

How to find files in Linux

The find command is part of the GNU Utils so it is available in any Linux distribution you can think of. So like any command, it has a basic syntax which is as follows

find [path] [parameters] [values] [values]

From what we can see, it is simple to use and now we will show some examples

• Find a file of which we know the name and extension:

find / -name name.txt 

Replace name with the name of the file. In this case, a file named name.txt will be searched for in the whole system.

• Search for files in a particular location.

find /home/angelo/ -name name.txt

• Doing case-insensitive searches

When searching by filename it is common to not remember whether it is upper or lower case. To do this, you can follow the following structure

find /home/angelo -iname name name.txt

Remember that you can modify the names and parameters to fit your criteria.

• Search for directories or folders

To search for directories we must use the type d parameter, it is as simple as this.

find / -type d -name documents

This will search for all folders named documents in the whole system. Also, you can change the search directory.

• Search files by extension

In this case, it is also useful to know how to search for files by extension. In this case, the option that will help us is type f.

find / -type f -name *.sh

Thus, in the above example, all files with the extension .sh in the system will be searched.

Other examples of the find command

It is also useful to know how to search for files by permissions, to do this use the perm parameter and the permission you want to search for.

find / -type f -perm 0775

or even, permissions different from the specified one

find / -type f ! -perm 775

• Search for empty files or folders

In this case, we can easily do it with these two commands

find / -type f -empty
find / -type d -empty

The first one works for files and the second one for directories or folders.

• Find files according to their modification date

For many sysadmins this can be very useful because we can perform a search according to the time it was modified.

find / -type f -mtime +21

In this case, all files that are older than 21 days since their last modification will be searched.

• Search files according to their size

Also, with the size option we can further filter our search. For example, we can search for files that weigh more than 10Mb.

find / -type f -size +10M

That is to say, with this we can be more effective.

So, enjoy it.

The post How to Find files in Linux? appeared first on Linux Windows and android Tutorials.

As a brief introduction, we will say that some of these tools are focused on Ubuntu but also support other distributions. So, let’s get started.

Linux Backup Tools

Back In Time

Back In Time is a simple backup tool for Linux, inspired by “flyback project”. It provides a command-line client ‘backintime’ and a Qt5 GUI ‘backintime-qt’ both written in Python3.

It is very easy to use because you only need to specify 3 things:

• Where to save snapshots
• What folders to backup
• Backup frequency (manual, every hour, every hour, every day, every month)

The installation is mainly focused on Ubuntu and derivatives like Linux Mint. It has versions for Plasma and GNOME that we can install by adding the PPA of the application.

sudo add-apt-repository ppa:bit-team/stable
sudo apt-get update
sudo apt-get install backintime-qt4

Then, we can start it from the main menu of the system.

Also, on the Github page, you can see the instructions to compile the program on another distribution and even generate DEB packages.

Grsync

Rsync is a CLi tool that is used by many to perform simple backups. However, the fact that you have to use the console, as well as many of the options can make it not ideal for everyone.

This is why Grsync was born to provide a graphical interface to this command. Although it provides support for the more advanced features of rsync, it does allow you to backup your folders quickly.

Sample uses of grsync include: synchronize a music collection with removable devices, backup personal files to a networked drive, replication of a partition to another one, mirroring of files, etc.

To install it on your favorite distribution you have to do it from the default package manager.

So, on Debian, Ubuntu, and derivatives you just need to run

sudo apt update
sudo apt install grsync

In the case of Fedora

sudo dnf install grsync

Or for Arch Linux based distributions

sudo pacman -S grsync

Then, start it from the main menu.

LuckyBackup

This is another tool that uses rsync as a backend for backups. But unlike Grsync, it is a more complete and reliable application.

It is simple to use, fast (transfers over only changes made and not all data), safe (keeps your data safe by checking all declared directories before proceeding in any data manipulation ), reliable, and fully customizable.

With LuckyBackup you can set which folders to back up and which not to back up. This increases operation times. It also includes a task scheduler so you can forget about backing up all the time. It even supports remote connections.

To install it on Debian and Ubuntu-based distributions just run

sudo apt update
sudo apt install luckybackup

In the case of Fedora, you have to run

sudo dnf install luckybackup

This way you only have to run it from the main menu.

Conclusion

These applications allow you to make backups in a fast and easy way so you don’t lose data in case of an unforeseen event. Each of them has its advantages and ease of use, now it’s your turn to use them.

The post Some Backup Tools on Linux appeared first on Linux Windows and android Tutorials.

The process of converting PDF to images is simple because we will do it using the pdftoppm tool that is run through the terminal.

According to the pdftoppm man page:

Pdftoppm converts Portable Document Format (PDF) files to color image files in Portable Pixmap (PPM) format, grayscale image files in Portable Graymap (PGM) format, or monochrome image files in Portable Bitmap (PBM) format.

However, it can also be used to generate PNG or JPEG files.

The pdftoppm command

This command is generally not installed by default on all Linux distributions. So we have to install it before using it.

So, for Debian and Ubuntu-based distributions, install the tool with the following command

sudo apt install poppler-utils

For CentOS, AlmaLinux, RockyLinux, and Fedora, you can install it using:

sudo dnf install poppler-utils

And for Arch Linux based distributions, you can run it with:

sudo pacman -S poppler

The use of the command is quite simple and has the following syntax:

pdftoppm [options] [PDF-FILE] [Output] [PDF-FILE] [PDF-FILE] [Output]

Also, like any command, you have options that modify the behavior of the command. Some of these options are:

• -f number: Specifies the first page to convert
• -l number: Specifies the last page to convert.
• -r number: Specifies the X and Y resolution, in DPI. The default is 150 DPI.
• -rx number: Specifies the X resolution, in DPI. The default is 150 DPI.
• -ry number: Specifies the Y resolution, in DPI. The default is 150 DPI.
• -scale-to number: Scales each page to fit in scale-to*scale-to pixel box.
• -scale-to-x number: Scales each page horizontally to fit in scale-to-x pixels.
• -scale-to-y number: Scales each page vertically to fit in scale-to-y pixels.
• -x number: Specifies the x-coordinate of the crop area top left corner
• -y number: Specifies the y-coordinate of the crop area top left corner

Convert PDF to Images

For this post, I have a PDF called sample.pdf with a large number of pages.

ls
sample.pdf

If you want a JPEG file to be generated for each of the pages, you can use the following command:

pdftoppm -jpeg sample.pdf exmple.jpeg

In this case, an image will be generated for each page and in this screenshot, you can see it better.

Also, you can define a range of pages to generate the images with the options -f and -l which define the first and the last page. For example:

pdftoppm -jpeg -f 2 -l 4 sample.pdf file.jpeg

In this case, only images of pages 2, 3, and 4 are generated.

As you can see the process is very simple and useful.

The post Convert a PDF to images on Linux appeared first on Linux Windows and android Tutorials.

According to the project website:

Vim is a highly configurable text editor built to make creating and changing any kind of text very efficient. It is included as “vi” with most UNIX systems and with Apple OS X.

Vim is rock stable and is continuously being developed to become even better. Among its features are:

• Persistent, multi-level undo tree.
• Extensive plugin system.
• Support for hundreds of programming languages and file formats
• Powerful search and replace
• Integrates with many tools

So we can say that Vim is an improved version of the mythical text editor Vi. This makes it very popular among sysadmin and even developers.

Install the Latest version of Vim

The best way to get the latest version of Vim is to compile it from the source code. It is lightweight, does not have many dependencies, and is more secure. So this is the way we will do it.

So, open a terminal or start an SSH session and run it:

sudo apt update
sudo apt upgrade

With the system upgrade, we can then install the build-essential package which contains the package compilation tools.

sudo apt install build-essential

Then create a folder where the compiler package will be. I have chosen this path:

mkdir -p /home/angelo/vim

But you can change it to whatever you want.

Then, download the packages needed to perform the compilation:

sudo apt install ncurses-dev unzip
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Note, selecting 'libncurses-dev' instead of 'ncurses-dev'
The following additional packages will be installed:
  libc-dev-bin libc6-dev linux-libc-dev
Suggested packages:
  glibc-doc manpages-dev ncurses-doc zip
Recommended packages:
  manpages-dev
The following NEW packages will be installed:
  libc-dev-bin libc6-dev libncurses-dev linux-libc-dev unzip
0 upgraded, 5 newly installed, 0 to remove and 36 not upgraded.
Need to get 4,902 kB of archives.
After this operation, 28.0 MB of additional disk space will be used.
Do you want to continue? [Y/n]

After that, download the Vim source code using the wget command.

wget https://github.com/vim/vim/archive/master.zip
--2021-02-15 17:54:39--  https://github.com/vim/vim/archive/master.zip
Resolving github.com (github.com)... 140.82.121.3
Connecting to github.com (github.com)|140.82.121.3|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://codeload.github.com/vim/vim/zip/master [following]
--2021-02-15 17:54:39--  https://codeload.github.com/vim/vim/zip/master
Resolving codeload.github.com (codeload.github.com)... 140.82.121.9
Connecting to codeload.github.com (codeload.github.com)|140.82.121.9|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [application/zip]
Saving to: ‘master.zip’

master.zip                                     [              <=>                                                                     ]  16.13M  5.85MB/s    in 2.8s    

2021-02-15 17:54:42 (5.85 MB/s) - ‘master.zip’ saved [16910770]

Now decompress it using the command unzip

unzip master.zip

Access the src folder inside the generated folder

cd vim-master/src

And start the compilation configuration taking as the path the folder we have created.

./configure --prefix=/home/angelo/vim

My recommendation, always when compiling a package from source code, I do it in a location that does not require root privileges and that I can manage. This way if we want to uninstall it, we would only delete the folder where the compilation was configured.

Create the package:

make

And finally, do the installation:

make install

To test the results, you can access the bin folder that has been created in the package creation path.

cd /home/angelo/vim/bin

There you will find the freshly compiled binary that you can start using. For example, I will show the compiled version.

./vim --version
VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Apr 26 2021 23:50:58)
 Included patches: 1-2814
 Compiled by angelo@osradar
 Huge version without GUI.  Features included (+) or not (-):

Output:

And that is it. Enjoy the latest version of Vim.

Conclusion

Having the latest stable version of a program gives us access to improvements and new features as well as bug fixes. Today I have shown you how to get the latest version of Vim quickly and easily.

The post How to install the latest version of Vim on Ubuntu 20.04 / Debian 10? appeared first on Linux Windows and android Tutorials.

What is Munin?

According to the Munin website:

Munin is a networked resource monitoring tool that can help analyze resource trends and “what just happened to kill our performance?” problems. It is designed to be very plug and play. A default installation provides a lot of graphs with almost no work.

Munin the monitoring tool surveys all your computers and remembers what it saw. It presents all the information in graphs through a web interface. Its emphasis is on plug and play capabilities. After completing a installation a high number of monitoring plugins will be playing with no more effort.

Using Munin you can easily monitor the performance of your computers, networks, SANs, applications, weather measurements and whatever comes to mind. It makes it easy to determine “what’s different today” when a performance problem crops up. It makes it easy to see how you’re doing capacity-wise on any resources.

So, let us get started.

Install Munin on DEbian 10

The first thing you have to do is to install some packages needed to run the Munin web client.

sudo apt update
sudo apt install apache2 apache2-utils libcgi-fast-perl libapache2-mod-fcgid

Then enable the Apache fcgid module:

sudo a2enmod fcgid

Now you can install munin and some additional packages such as those containing the plugins and for the node.

sudo apt install munin munin-node munin-plugins-extra

As Muni is accessible from the web, it is convenient to request a username and password to make sure that not just anyone can log in and see the information.

htpasswd -c /etc/munin/munin-htpasswd admin
New password:
Re-type new password:
Adding password for user admin

You can replace admin with the user of your choice.

Then, enable the default VirtualHost configuration for Munin:

sudo cp -p /etc/munin/apache24.conf /etc/apache2/sites-available/munin.conf

Enable the new VirtualHost:

sudo a2ensite munin
sudo systemctl reload apache2

Before using Munin, it is advisable to make some modifications to the virtualhost.

sudo nano /etc/apache2/sites-available/munin.conf

And leave the file as follows:

ScriptAlias /munin-cgi/munin-cgi-graph /usr/lib/munin/cgi/munin-cgi-graph
Alias /munin/static/ /var/cache/munin/www/static/

<Directory /var/cache/munin/www>
AuthUserFile /etc/munin/munin-htpasswd
Authtype Basic
AuthName "Munin"
Require valid-user
Options FollowSymLinks SymLinksIfOwnerMatch
Options None
</Directory>

   <Directory /usr/lib/munin/cgi>
    AuthUserFile /etc/munin/munin-htpasswd
    Authtype Basic
    AuthName "Munin"
    Require valid-user
    Options FollowSymLinks SymLinksIfOwnerMatch
    
   <IfModule mod_fcgid.c>
        SetHandler fcgid-script
    </IfModule>
    <IfModule !mod_fcgid.c>
        SetHandler cgi-script
    </IfModule>
</Directory>

Save the changes and close the editor.

And to apply the changes, restart Apache and munin.

sudo systemctl restart apache2 munin-node

Access to Munin interface

Now all you have to do is to verify that the server is working properly and to do this you just have to open a web browser and access http://your-server/munin and you will see the following

So, Munin is working but you need to add nodes.

The post Install Munin on Debian 10 appeared first on Linux Windows and android Tutorials.

Well, quickly we can say that nano is a text editor in the terminal. It stands out for its ease of use and speed. With this editor, we can open and modify text files and settings from the terminal. All this without sacrificing resources and comfortably.

Besides basic text editing, nano offers features like undo/redo, syntax coloring, interactive search-and-replace, auto-indentation, line numbers, word completion, file locking, backup files, and internationalization support

As we may suspect, nano is open source and is included in almost all Linux distributions that exist. But for a strange reason, we never can use the latest version and that nano has very active development.

So, the possibility we have is to compile it manually but there is another simpler method if we use homebrew.

Install the latest version of nano on Ubuntu 20.04

The process of having the latest version of nano in Ubuntu 20.04 easily and simply is thanks to Homebrew.

We have talked about Homebrew and we think it is a fabulous tool that allows you to install applications quickly and easily as Hugo.

Well, nano is also available to be installed using this tool and the best thing is that we can have the latest stable version.

So, first install Homebrew

How to install Homebrew on Ubuntu 20.04?

Once Homebrew is perfectly configured we can continue.

Check the current version of nano with the following command:

nano --version
GNU nano, version 4.8
  (C) 1999-2011, 2013-2020 Free Software Foundation, Inc.
  (C) 2014-2020 the contributors to nano
  Email: nano@nano-editor.org    Web: https://nano-editor.org/
  Compiled options: --disable-libmagic --enable-utf8

As you can see, the version is a little old, so don’t have problems, uninstall it.

sudo apt autoremove nano

And now install the latest version of nano

brew install nano

And at the end, check the installed version

nano --version

Now create a test file

nano text.txt

And add some text

You now have the latest version of nano on your system. Something simpler than it seems and that can be useful at any time.

The post How to install the latest version of nano on Ubuntu 20.04? appeared first on Linux Windows and android Tutorials.

Nu shell?

Let’s start with the basics. What is Nu Shell? Well, Nu shell is a new terminal, released under the MIT license and created in Rust with a different paradigm than others. According to its official documentation the goal of this project is “to take the Unix philosophy of shells, where pipes connect simple commands together, and bring it to the modern style of development”.

So, we can say with these objectives that Nu Shell intends to modernize the output of some commands in the terminal. Adapting them to situations less complex to understand and ideal for developers or sysadmin.

Install it on Ubuntu 20.04

Nu Shell is created in Rust. For tango we can use the Rust package manager called cargo. However, obviously the first step is to install Rust on Linux.

How to install Rust on Ubuntu 20.04 / Debian 10?

Then, you have to install some dependencies. If you use Debian, Ubuntu or one of their dervidas, just use this command:

:~$ sudo apt install pkg-config libssl-dev libxcb-composite0-dev libx11-dev

And then, if we can start the installation.

:~$ cargo install nu --all-features

And we wait for the process to end.

Using Nu Shell

The first thing to say is that the official documentation of the project is quite good. And we will use it for some illustrative examples.

To start the program just use the following command:

:~$ nu

And to exit the application, just run exit.

To see a sample of the potential of the application, let’s use the command ls in any directory. Remember that the command ls shows the files in a directory.

As we can see that is the content of the carptea Music of my system. But what stands out is the way in which the command is presented to us, different from the typical Linux terminal.

Easily and quickly we can have information about the files in a folder. But the strength of the application are the pipes and the filters. What if we want to show only the folders?

I will go back to my personal folder and from there I will illustrate the example.

Just, run:

:~$ ls | where type == Directory

And that’s how fast and easy we can use the ls command.

Let’s see what the date command looks like.

If you use a lot of Linux, you will know that the ps command lists the active processes of our computer.

Of course there are many more utilities that are available in the official project documentation.

Over time they will improve and incorporate others. In addition to polishing others.

So, enjoy it.

Conclusion

Nu shell is profiled as a revolutionary terminal that wants to adapt the shell to today’s needs without many problems. If you are sysadmin or work a lot with the terminal thank applications like this.

It still has a long way to go but thanks to the official documentation it is possible to get a lot out of it.

One last detail that I forgot to mention is that the application has autocomplete that makes the job even easier.

The Nu Shell official documentation

GitHub site.

The post Install Nu Shell on Ubuntu 20.04 appeared first on Linux Windows and android Tutorials.

To recover deleted messages you will need an app called WAMR. This app is capable of reading messages from your notifications and creating a backup of messages based on your notification history. When the app detects that a message has been deleted it will immediately show you a notification.

Besides, this app allows you to recover media files that have been deleted, such as photos, videos, voice notes, audio, animated gifs, and stickers. Also includes a function to download Statuses.

Installing WAMR

To download and install WARM you can do it directly from the Google Play store, following the link below:

WAMR – Recover deleted messages & status download

First step

Open the app, the app will show you a disclaimer. Then accept The Terms & Conditions and The Privacy Policy.

Second step

The app will request you to select which applications you want to monitor, select the ones you want (the service is only available for some of them)

Third step

Finally, the app will request you to enable some permissions.
In the first one, you will press the Enable button. After that, you will redirect to the Autostart settings, then you will grant the permissions to WAMR.

Now go back to the permission screen and go to the second permission option and press Enable, then the application will ask you for permission to access the internal storage of your device; you have to press the Allow button.

Again go back to the permission screen press Enable on the third permission option. After that, you will redirect to the Notification access settings, then you will grant the permissions to WAMR.

Final Result

After you finish the initial setup you will see the notification history plus two tabs, one for deleted media and the other one for downloading statuses. And that’s it, you can start enjoying the benefits of this app now.

Conclusion

The WAMR app is an incredible tool that can be useful to us. Now when someone sends you a message that has already been deleted you won’t be left in the dark again. in addition to being able to download statuses without problems. We hope to bring you even more tools to get the maximum benefit from your devices. Thank you for reading.

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