How to use sudo on RHEL, CentOS, AlmaLinux, Rocky Linux or Oracle Linux

Red hat on a mysterious woman (generated by Midjourney). Credit: libre-software.net. License: CC BY-SA 4.0

How to use sudo on RHEL, CentOS, AlmaLinux, Rocky Linux or Oracle Linux

Last updated on October 6, 2022

This short howto is about setting up sudo on Red Hat Entreprise Linux (RHEL) and its derivates – for example CentOS, AlmaLinux, Rocky Linux or Oracle Linux. It also gives a quick introduction on using the vi text editor through visudo.

Becoming root: su & sudo

CentOS, Scientific Linux and RHEL do not use sudo as Ubuntu does. Instead, you are supposed to use su or su root to get higher permissions. su stands for super user or switch user. Type exit to exit the superuser mode. More information on su on the CentOS Wiki.

After years using Ubuntu and Linux Mint, I got used to sudo. To be able to run sudo on CentOS, one has to add the current user to the /etc/sudoers file. Editing the sudoers file is done via the visudo utility.

Editing sudoers with visudo

Visudo edits the sudoers file in a safe fashion, locks the sudoers file against multiple simultaneous edits, provides basic sanity checks, and checks for parse errors. (from the visudo man page)

You can only run visudo as root, so that we’ll need to run su:
su root

The next step is to run visudo without any parameters. It will open the /etc/sudoers file in vi (a text editor):
visudo

Using the vi text editor

There is no need to be familiar with vi, just to know the some basics. Vi has two so called “modes”:
– The insert mode allows you to insert/write text
– The command mode is for saving files, text manipulation and much more.

To edit a file, type i to enter the insert mode.
Press Esc to exit the insert mode and enter the command mode.

In command mode, use a : colon to start commands:

Press : + w + q + Enter to save your changes and exit (write and quit)

Type : + q + ! + Enter to exit without saving changes.

Add yourself to the sudoers in visudo

All you have to do now is to add the following line at the end of the file (press i to enter insert mode):
user_name ALL=(ALL) ALL

ALL must be written in capital letters. Replace user_name with your user name.

Visudo - Adding user to sudoers in CentOS, Scientific Linux and RHEL

Finally, press Esc to enter the command mode, and : + w + q + Enter to save and exit the editor. Changes are effective immediately, you may now use sudo.

N.B. If you plan to use Truecrypt, comment out the following line in /etc/sudoers by inserting a dash:
#Default requiretty

By Johannes Eva, 2012 – October 2022

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Comments

29 thoughts on “How to Install Firefox on Linux Mint, Ubuntu, Debian or any other Linux distribution”

  2. John

    I was wanting to update Firefox on my Ubuntu Trusty (14.04). I finally came across this article and … tahdah. Now I have Firefox 83 installed and working perfectly. Thank you so much for this article. One question – can I also install the latest Thunderbird in the same manner?
    And please folks, no comments like – just upgrade to the newest Ubuntu. Trusty works perfect. I have Apache installed and it works perfect also. So why should I update/upgrade to a newer version when I have perfection now. You know the old saying – If it works don’t fix it.

  4. Maëlle

    Hello, I’m French.
    It’s hard to me to understand English so when it’s electronic language, it’s very very hard. But I tried (even if I doesn’t understand, even while translating). And when I tried, I succeed to extract the file (yeeaah!) but I can’t move Firefox to /opt, it says “no such file or directory” like Kurman (an other user). But how am I doing now ? I search a lot of solutions and nothing works. Netflix doesn’t want to work with my old Firefox (the 66.0.3 version). Am I going to get there someday? After Netflix, it will be some important things…

    Please, help me. (Once I could watch Netflix…)

    Thanks for the article!

  5. Simon

    Note: When the default version of Firefox is upgraded by the system, the symlink /usr/bin/firefox is overwritten and you will either have re-create it or just lock the currently installed version in Synaptic to prevent that from happening altogether:

  7. Michael Biller

    Great article. In the case of Firefox newer is better. Every update since Quantum debuted has brought it closer to perfection. Oh, I think it may be ‘inexperienced’, rather than ‘unexperienced’. Regardless, the advice is sound.

    It’s always best for newbies to practice caution. Then again, it took a few self inflicted system meltdowns to really start getting the hang of this Linux thing.

  8. Coruscant

    @Rafael: no, you won’t loose your Firefox settings. These are stored in your profile folder. On Linux, you profile folder is in your home directory, in the .mozilla/firefox sub-folder. You may need to show hidden files and folders (use Ctrl + H or the “View” menu) to navigate to the profile folder.

    If you only have one profile, its folder has “default” in the name. The complete path of the Firefox profile folder will be something like:
    /home/user_name/.mozilla/firefox/random_string.default

    This folder allows for an awful lot of flexibility, for example you can:

    • backup it,
    • copy it to a new system, and even
    • share it between a Linux and a Windows system (if it’s located within an NTFS file system).
  10. Coruscant

    Thank you, this is indeed useful. Installing Firefox from .deb packages is also a viable option. Keep in mind that the recommendation is the same as when installing from the tar.gz archive: “it is strongly suggested to use a package manager like aptitude or synaptic to download and install packages, instead of doing so manually via this website.”

  12. Geoffrey Morrison

    Make friends with the terminal!

    Sure, it’s been quite some time since 2015: Users must extract from the “tar” archive and use a password-enabled (root) terminal (or sudo) to perform the subsequent file actions. Simply invoking a file manager and then copying/pasting won’t work.

    The reason Debian users end up here:

    Note that Debian’s repository version of Firefox still is named “firefox-esr,” not simply “firefox” (Before, it was “iceweasel” – a legality, still in effect with firefox-esr): Debian proves perhaps the most conservative distro in the Linux realm. As was noted in an old saying: “They wear both a belt and suspenders!”

    The problem is that institutions performing secure transactions (say, global financial corporations) – along with many still-perplexed users (who generally aren’t bare novices) – dislike legacy browser versions. Debian purists dislike the corporate bent of Mozilla’s Firefox development. (After all, it’s firefox.com, not firefox.org.)

  14. Coruscant

    Kumar, you’re probably in the wrong directory when running the move command – or using the wrong file name. Using the TAB key to autocomplete the file name helps to know if you’re right: if it autocompletes the file or directory names, it’s right, else it’s wrong. Of course, listing files with the ls command also shows if you have extracted the archive correctly.

  15. Sathis Kumar

    I’ve extracted the file but I can’t move it to /opt, it says no such file or directory.

  17. Coruscant

    I also run Mint 17.3, the Firefox version is 45 and it should be updated to 46 very soon. I can’t explain why you’re stuck with an older version. I suppose you ran sudo apt-get update? If nothing else works, I would suggest to install the newest Firefox version manually as described in this guide.

    Update: The update to Firefox 46 just showed up in the update manager. It took 4 days to the Linux Mint team to check and distribute the update, which is fine.

  18. JimM

    You state here, and I’ve seen in other places, that Debian-based package managers will release firefox updates “just a few days after the official release”. That has not been my experience. I run Linux Mint 17.3, and as of today (4/30/2016), my firefox from the package manager is version 42.0. The following version (43.0) was released 4.5 months ago on December 15th, and version 46.0 was released this week. What am I missing?

  19. Pingback: Install the latest FireFox in CentOS 7 - UncleNinja

  20. Pingback: Upgrade Firefox di Linux Mint | Catatan dan Wiki Personal

  22. rijnsma

    FF 45 in Mint does not open groups of tabs anymore. So that seems broken.
    I went back to a former version. The repository only offered FF 28… But this one still works.

  23. Josetto

    I figured out something, I turned off check for default application in settings (during start of application, it ignored it 🙂 ) I hope it will work

  24. Josetto

    I have other problem 🙂 I unpacked firefox (did same with thunderbird), created symbolic links and everything, but still, when I run firefox or thunderbird, it said it is not default browser/email client and I can’t turn it off. It is not really functional problem, but it is reaaaaaally annoying 🙂 in preffered applications is set firefox and thunderbird (the original mint firefox and thunderbird don’t have this problem), is there any way (and I am sure there is) how to set unzipped TB and FF as default? BTW I am using common profiles for windows and for mint 17.3 in both applications. THX 🙂

  25. Coruscant

    Well, in fact this tutorial is for advanced users, most of which are installing Firefox on their own on custom Linux systems. Or trying Firefox Beta/Aurora or other special versions of Firefox.

    In your case you’re probably using mainstream distributions such are Ubuntu, Linux Mint, Debian, OpenSuse, Fedora, … The package manager of your distro will take care of updating Firefox by itself, when when the new Ffox version has been tested for compatibility with your distro, so that it doesn’t break anything. On Ubuntu or Linux Mint, for example, it takes just a few days after the official release.

    Please do NOT use this guide to update Firefox by hand if you’re just a “normal” user or a Linux beginner. Just apply the normal updates (as you should always do) for your distribution and you’ll get the new Firefox version. I’ll try to make a version of this guide for beginners and normal users soon, as it seems to be really confusing. Sorry for that.

  26. me

    I really do try to like Linux… but I just can’t understand why I can’t just UPDATE my firefox in one click? The version is there – why do I need to start entering commands and copying folders for something as trivial as that?

  27. Pingback: How to install Firefox 43 on Linux Mint, Ubuntu, Debian, CentOS, Fedora - Free Networking Tutorials, Free System Administration Tutorials and Free Security Tutorials

  28. Coruscant

    Ubuntu will take care of Firefox upgrades automatically, you don’t have to do it manually. It may take a few days after the official release for the Firefox upgrade to show on, because the Ubuntu folks have to test the new release with Ubuntu.

    There is no Firefox install in /opt by default, as this is where admins/users are supposed to install optional software. If you did not install anything in /opt manually, nothing show up there, which is normal.
    Hope this helps!

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