What is super user linux

How do I become superuser on Ubuntu Linux using su/sudo?

I replaced Windows 10 with Ubuntu Linux 16.04 LTS. So, I am a new Ubuntu Linux user. How do I become superuser on Ubuntu Linux? How do I login as root on Ubuntu?

Introduction: On Ubuntu Linux root is a particular user account. By default, the root user has access to all commands, files, services on an Ubuntu Linux operating system. It is also known as the root account, root user and the superuser. The superuser or root user has root privileges. It is the most privileged account on Ubuntu with complete access to everything. The MS-Windows equivalent of root is the Administrators group or Administrator user. This page shows how to log in as root or superuser on Ubuntu to perform sysadmin related tasks.

Tutorial details
Difficulty level	Easy
Root privileges	Yes
Requirements	Ubuntu Linux
Est. reading time	3 minutes

How to become superuser on Ubuntu Linux

1. Open a terminal Window/App. Press Ctrl + Alt + T to open the terminal on Ubuntu.
2. To become root user type:
   sudo -i
   OR
   sudo -s
3. When promoted provide your own password.
4. After successful login, the $ prompt would change to # to indicate that you logged in as root user on Ubuntu.
5. You can also type the whoami command to see that you logged as the root user.

Let us see all commands and examples in details.

How do I login as root on Ubuntu?

Open the Terminal application. Use the whoami command to verify user identity:
$ whoami
To login as root on Ubuntu, type the following sudo command:
$ sudo -i
Next type your password and your shell promot should change from $ to # :
#
To exit from sudo session of root user, type any one of the following exit command or logout command:
# logout
OR
# exit

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How to become superuser on Ubuntu Linux using sudo command

The -i option tells sudo to run the shell specified by the root user’s password database entry as a login shell. If you pass the -s to the sudo command, it runs the shell specified by the SHELL environment variable if it exists or the shell defined by the invoking user’s password database entry.

How to become root in Ubuntu Linux using su

By default, the root account password is locked in Ubuntu Linux for security reasons. This means that you cannot login as root directly or use the su command to become the root user. You must set up root password by running the following command in advance on Ubuntu based system:
sudo passwd root
See “How to change root password in Ubuntu Linux” for more info.

Type the following su command:
$ su —
You must know and type root user’s password when prompted:

Login as root on Ubuntu Linux using ‘su -‘ command

su vs sudo to become superuser in Ubuntu Linux

Table 01 – Difference between su and sudo

su command	sudo command
You must know the root user’s password.	No need to know the root user’s password.
The su command does not log usage or all arguments.	The sudo command logs sudo usage and all arguments.
If the root user password not set or root user is disabled, you can not use su command.	sudo works with or without a root user password. It uses your password and /etc/sudoers file to authenticate your session.

Conclusion

This tutorial explains how to gain root access in the Ubuntu Linux terminal session using the sudo and su command. I recommend that you always use the sudo command to become root user on Ubuntu. For more info see this page.

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Linux Login as Superuser ( root user )

Linux superuser

In Linux and Unix like computer operating systems, root is the conventional name of the user who has all rights or permissions (to all files and programs) in all modes (single- or multi-user). The root user can do many things an ordinary user cannot, such as changing the ownership of files and binding to ports numbered below 1024. The etymology of the term may be that root is the only user account with permission to modify the root directory of a Unix system.

Linux Login as Superuser

You need to use any one of the following command to log in as superuser / root user on Linux:

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1. su command – Run a command with substitute user and group ID in Linux
2. sudo command – Execute a command as another user on Linux

How to become superuser in Linux

Let us see some examples of the su and sudo command to become superuser in Linux.

Become a superuser in Linux using sudo command

You must be part of special secondary group on Linux:

• sudo group on a Debian or Ubuntu Linux
• wheel group on a CentOS/RHEL/Fedora/Oracle Linux

You can see your secondary group membership by running either groups command or id command $ groups
$ id
Next run the following command to become a root/super user:
$ sudo -i
When promoted type your password to gain root shell.

Log in as a superuser/root user using the sudo command on Linux

Superuser login

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Category	List of Unix and Linux commands
Documentation	help • mandb • man • pinfo
Disk space analyzers	df • duf • ncdu • pydf
File Management	cat • cp • less • mkdir • more • tree
Firewall	Alpine Awall • CentOS 8 • OpenSUSE • RHEL 8 • Ubuntu 16.04 • Ubuntu 18.04 • Ubuntu 20.04
Linux Desktop Apps	Skype • Spotify • VLC 3
Modern utilities	bat • exa
Network Utilities	NetHogs • dig • host • ip • nmap
OpenVPN	CentOS 7 • CentOS 8 • Debian 10 • Debian 8/9 • Ubuntu 18.04 • Ubuntu 20.04
Package Manager	apk • apt
Processes Management	bg • chroot • cron • disown • fg • glances • gtop • jobs • killall • kill • pidof • pstree • pwdx • time • vtop
Searching	ag • grep • whereis • which
Shell builtins	compgen • echo • printf
Text processing	cut • rev
User Information	groups • id • lastcomm • last • lid/libuser-lid • logname • members • users • whoami • who • w
WireGuard VPN	Alpine • CentOS 8 • Debian 10 • Firewall • Ubuntu 20.04

Comments on this entry are closed.

i like to learning more about linux

It is interesting to notice how easy it is to find this information on the web, how to login as a superuser, and how it is difficult to find the information about how to log OUT of superuser (exit). Wouldn’t it make sense to put these things together ? I guess that someone who just learnt how to log in as a superuser would also immediately need to know how to log out.
And by the way, your answer after “A” doesn’t answer the questions “Q” at the beginning of the article.

Hey, i tried this but my linux said:
Error with approval ( think thats how you translate it..
its bothering me alot and i tripple checked the password it is correct

what version of lunux are you using? if you are using any ubuntu based linux for example you, you can only use the super user to run comands, you cant stay loged in as the super user.

Ex: to install an aplication, you would opne a terminal and enter

sudo apt-get install name_of_application.

the sudo or su comand will indicate to linux that you are trying to run the comand as the super user or administrator, but in ubuntu after the application is done installing it will go back to regular user to aboid any security breach. y have to realize that the when you are in super user mode it can be verry danguros becasue bc you can do anything, like deleting all you files and messing up your operating system.

so in conclution you get that message because your linux you might not be running any other comands after the sudo or su comand.

i hope that made sense.

i am grave trouble i forgot ma superuser password hw to recover it

I am new to linux, i want to learn more about linux as much possible. i am using ubuntu and suse.
i try to log in as supper user by su command, and provide password i used to login my system but it shows Authentication failure. please guide me.

Thanks and regards

Earlier i used to login to root by typing ip address and port, i just remember the ip address but i forgot the port number, can anybody please help.

I think you are using telnet or ssh, if telnet it is port 23 and for ssh it uses port 22. Hope it helps.

i just now logged in as super user but i want to delete it.what i should do for that.

All you need to do is type: Exit

or press Control D

thanks for this! learning linux command line scripts now after installing fedora in my nephew’s inspiron 1525, was wondering how to get to root user, other sites weren’t explaining well enough so again, thanks a million! 🙂

Being a super user can be VERY dangerous so I suggest you know what your doing if your going to become a super user but another way to get root access is to type into the command line:

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What is Linux?

From smartphones to cars, supercomputers and home appliances, home desktops to enterprise servers, the Linux operating system is everywhere.

Linux has been around since the mid-1990s and has since reached a user-base that spans the globe. Linux is actually everywhere: It?s in your phones, your thermostats, in your cars, refrigerators, Roku devices, and televisions. It also runs most of the Internet, all of the world’s top 500 supercomputers, and the world’s stock exchanges.

But besides being the platform of choice to run desktops, servers, and embedded systems across the globe, Linux is one of the most reliable, secure and worry-free operating systems available.

Here is all the information you need to get up to speed on the Linux platform.

What is Linux?

Just like Windows, iOS, and Mac OS, Linux is an operating system. In fact, one of the most popular platforms on the planet, Android, is powered by the Linux operating system. An operating system is software that manages all of the hardware resources associated with your desktop or laptop. To put it simply, the operating system manages the communication between your software and your hardware. Without the operating system (OS), the software wouldn?t function.

The Linux operating system comprises several different pieces:

1. Bootloader – The software that manages the boot process of your computer. For most users, this will simply be a splash screen that pops up and eventually goes away to boot into the operating system.
2. Kernel – This is the one piece of the whole that is actually called ?Linux?. The kernel is the core of the system and manages the CPU, memory, and peripheral devices. The kernel is the lowest level of the OS.
3. Init system – This is a sub-system that bootstraps the user space and is charged with controlling daemons. One of the most widely used init systems is systemd? which also happens to be one of the most controversial. It is the init system that manages the boot process, once the initial booting is handed over from the bootloader (i.e., GRUB or GRand Unified Bootloader).
4. Daemons – These are background services (printing, sound, scheduling, etc.) that either start up during boot or after you log into the desktop.
5. Graphical server – This is the sub-system that displays the graphics on your monitor. It is commonly referred to as the X server or just X.
6. Desktop environment – This is the piece that the users actually interact with. There are many desktop environments to choose from (GNOME, Cinnamon, Mate, Pantheon, Enlightenment, KDE, Xfce, etc.). Each desktop environment includes built-in applications (such as file managers, configuration tools, web browsers, and games).
7. Applications – Desktop environments do not offer the full array of apps. Just like Windows and macOS, Linux offers thousands upon thousands of high-quality software titles that can be easily found and installed. Most modern Linux distributions (more on this below) include App Store-like tools that centralize and simplify application installation. For example, Ubuntu Linux has the Ubuntu Software Center (a rebrand of GNOME Software? Figure 1) which allows you to quickly search among the thousands of apps and install them from one centralized location.

Why use Linux?

This is the one question that most people ask. Why bother learning a completely different computing environment, when the operating system that ships with most desktops, laptops, and servers works just fine?

To answer that question, I would pose another question. Does that operating system you?re currently using really work ?just fine?? Or, do you find yourself battling obstacles like viruses, malware, slow downs, crashes, costly repairs, and licensing fees?
If you struggle with the above, Linux might be the perfect platform for you. Linux has evolved into one of the most reliable computer ecosystems on the planet. Combine that reliability with zero cost of entry and you have the perfect solution for a desktop platform.

That’s right, zero cost of entry… as in free. You can install Linux on as many computers as you like without paying a cent for software or server licensing.

Let’s take a look at the cost of a Linux server in comparison to Windows Server 2016. The price of the Windows Server 2016 Standard edition is $882.00 USD (purchased directly from Microsoft). That doesn’t include Client Access License (CALs) and licenses for other software you may need to run (such as a database, a web server, mail server, etc.). For example, a single user CAL, for Windows Server 2016, costs $38.00. If you need to add 10 users, for example, that’s $388.00 more dollars for server software licensing. With the Linux server, it?s all free and easy to install. In fact, installing a full-blown web server (that includes a database server), is just a few clicks or commands away (take a look at ?Easy LAMP Server Installation? to get an idea how simple it can be).

If zero cost isn’t enough to win you over? what about having an operating system that will work, trouble free, for as long as you use it? I’ve used Linux for nearly 20 years (as both a desktop and server platform) and have not had any issues with ransomware, malware, or viruses. Linux is generally far less vulnerable to such attacks. As for server reboots, they’re only necessary if the kernel is updated. It is not out of the ordinary for a Linux server to go years without being rebooted. If you follow the regular recommended updates, stability and dependability are practically assured.

Open source

Linux is also distributed under an open source license. Open source follows these key tenants:

• The freedom to run the program, for any purpose.
• The freedom to study how the program works, and change it to make it do what you wish.
• The freedom to redistribute copies so you can help your neighbor.
• The freedom to distribute copies of your modified versions to others.

These points are crucial to understanding the community that works together to create the Linux platform. Without a doubt, Linux is an operating system that is ?by the people, for the people?. These tenants are also a main factor in why many people choose Linux. It?s about freedom and freedom of use and freedom of choice.

What is a “distribution?”

Linux has a number of different versions to suit any type of user. From new users to hard-core users, you’ll find a “flavor” of Linux to match your needs. These versions are called distributions (or, in the short form, “distros”). Nearly every distribution of Linux can be downloaded for free, burned onto disk (or USB thumb drive), and installed (on as many machines as you like).

Popular Linux distributions include:

• LINUX MINT
• MANJARO
• DEBIAN
• UBUNTU
• ANTERGOS
• SOLUS
• FEDORA
• ELEMENTARY OS
• OPENSUSE

Each distribution has a different take on the desktop. Some opt for very modern user interfaces (such as GNOME and Elementary OS’s Pantheon), whereas others stick with a more traditional desktop environment (openSUSE uses KDE).

You can check out the top 100 distributions on the Distrowatch.

And don’t think the server has been left behind. For this arena, you can turn to:

• Red Hat Enterprise Linux
• Ubuntu Server
• Centos
• SUSE Enterprise Linux

Some of the above server distributions are free (such as Ubuntu Server and CentOS) and some have an associated price (such as Red Hat Enterprise Linux and SUSE Enterprise Linux). Those with an associated price also include support.

Which distribution is right for you?

Which distribution you use will depend on the answer to three simple questions:

• How skilled of a computer user are you?
• Do you prefer a modern or a standard desktop interface?
• Server or desktop?

If your computer skills are fairly basic, you’ll want to stick with a newbie-friendly distribution such as Linux Mint, Ubuntu (Figure 3), Elementary OS or Deepin. If your skill set extends into the above-average range, you could go with a distribution like Debian or Fedora. If, however, you’ve pretty much mastered the craft of computer and system administration, use a distribution like Gentoo. If you really want a challenge, you can build your very own Linux distribution, with the help of Linux From Scratch.

If you’re looking for a server-only distribution, you will also want to decide if you need a desktop interface, or if you want to do this via command-line only. The Ubuntu Server does not install a GUI interface. This means two things your server won’t be bogged down loading graphics and you’ll need to have a solid understanding of the Linux command line. However, you can install a GUI package on top of the Ubuntu Server with a single command like sudo apt-get install ubuntu-desktop. System administrators will also want to view a distribution with regards to features. Do you want a server-specific distribution that will offer you, out of the box, everything you need for your server? If so, CentOS might be the best choice. Or, do you want to take a desktop distribution and add the pieces as you need them? If so, Debian or Ubuntu Linux might serve you well.

Installing Linux

For many people, the idea of installing an operating system might seem like a very daunting task. Believe it or not, Linux offers one of the easiest installations of all operating systems. In fact, most versions of Linux offer what is called a Live distribution ? which means you run the operating system from either a CD/DVD or USB flash drive without making any changes to your hard drive. You get the full functionality without having to commit to the installation. Once you’ve tried it out, and decided you wanted to use it, you simply double-click the “Install” icon and walk through the simple installation wizard.

Typically, the installation wizards walk you through the process with the following steps (We’ll illustrate the installation of Ubuntu Linux):

• Preparation: Make sure your machine meets the requirements for installation. This also may ask you if you want to install third-party software (such as plugins for MP3 playback, video codecs, and more).
• Wireless setup (if necessary): If you are using a laptop (or machine with wireless), you’ll need to connect to the network, in order to download third-party software and updates.
• Hard drive allocation (Figure 4): This step allows you to select how you want the operating system to be installed. Are you going to install Linux alongside another operating system (called “dual booting”), use the entire hard drive, upgrade an existing Linux installation, or install over an existing version of Linux.
• Location: Select your location from the map.
• Keyboard layout: Select the keyboard for your system.
• User setup: Set up your username and password.

That’s it. Once the system has completed the installation, reboot and you’re ready to go. For a more in-depth guide to installing Linux, take a look at “How to Install and Try Linux the Absolutely Easiest and Safest Way” or download the Linux Foundation’s PDF guide for Linux installation.

Installing software on Linux

Just as the operating system itself is easy to install, so too are applications. Most modern Linux distributions include what most would consider an app store. This is a centralized location where software can be searched and installed. Ubuntu Linux (and many other distributions) rely on GNOME Software, Elementary OS has the AppCenter, Deepin has the Deepin Software Center, openSUSE has their AppStore, and some distributions rely on Synaptic.

Regardless of the name, each of these tools do the same thing? a central place to search for and install Linux software. Of course, these pieces of software depend upon the presence of a GUI. For GUI-less servers, you will have to depend upon the command-line interface for installation.

Let’s look at two different tools to illustrate how easy even the command line installation can be. Our examples are for Debian-based distributions and Fedora-based distributions. The Debian-based distros will use the apt-get tool for installing software and Fedora-based distros will require the use of the yum tool. Both work very similarly. We’ll illustrate using the apt-get command. Let’s say you want to install the wget tool (which is a handy tool used to download files from the command line). To install this using apt-get, the command would like like this:

The sudo command is added because you need super user privileges in order to install software. Similarly, to install the same software on a Fedora-based distribution, you would first su to the super user (literally issue the command su and enter the root password), and issue this command:

That’s all there is to installing software on a Linux machine. It’s not nearly as challenging as you might think. Still in doubt? Recall the Easy Lamp Server Installation from earlier? With a single command:

You can install a complete LAMP (Linux Apache MySQL PHP) server on either a server or desktop distribution. It really is that easy.

More resources

If you’re looking for one of the most reliable, secure, and dependable platforms for both the desktop and the server, look no further than one of the many Linux distributions. With Linux you can assure your desktops will be free of trouble, your servers up, and your support requests minimal.

For more information to help guide you through your lifetime with Linux, check out the following resources:

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