If you've lost root credentials you can always bypass them.
https://www.tecmint.com/reset-forgotten-root-password-in-ubuntu/
When your in after this point you can reset the password to something you know then continue from there.
this post was submitted on 11 Aug 2023
94 points (95.2% liked)
Linux
50514 readers
671 users here now
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
Rules
- Posts must be relevant to operating systems running the Linux kernel. GNU/Linux or otherwise.
- No misinformation
- No NSFW content
- No hate speech, bigotry, etc
Related Communities
Community icon by Alpár-Etele Méder, licensed under CC BY 3.0
founded 5 years ago
MODERATORS
Thanks. I will try that when I get home from work and give you my feedback.
Someone has already given you a guide on how to change the password via grub params, however that might not be necessary. It's important that when you ask these questions you provide the exact command you're using and the exact things you changed, what I assume happened is that you removed yourself from the wheel group (which in Mint might be listed as Admin privileges), this is important because the sudo command (unless you've customised it) only works for members of the wheel group. Then you said you tried to access the root via terminal and it told you you didn't have permissions, I'm 99% sure that you tried something with sudo here, which will no longer work because your user is not an admin anymore.
So are you screwed? Nope, you can access the root user without the need for sudo. Most people when they want to have a root shell use sudo su, in that command su is the actual part that lets you login as root (in fact su is short for ~~Switch~~ Substitute User, and you can switch to any user using it. Fun fact sudo is a short for ~~Switch~~ Substitute User and DO, so that you can run things as root without needing to login as root). As you might have already guessed just running su and putting the root password should work. Then why do people use sudo su? Because sudo su will ask you for YOUR password, whereas su asks you for the ROOT password (which in most servers is different, but most home computers is the same). You set the two of them when installing the system (in fact it's very likely that you ticked a checkbox that said something like "use the same password for the root account").
Edit: The correct therm used in the su manual is Substitute not switch as someone mentioned in a reply.
Huh, I always thought su stands for super user, but apparently it actually stands for substitute user (according to the manpage)
I don't think "substitute user" is the original meaning, and it's more like a retroactively applied acronym.
Looking at various old Unix manpages, it said various things in the past. In the HP-UX documentation it even lists three different variants in the same man page: "switch user", "set user" and "superuser".
"superuser" is probably the original meaning, because that's what it says in the Unix Manual 1st edition (1971): http://man.cat-v.org/unix-1st/1/su
NAME su -- become privileged user
SYNOPSIS su password
DESCRIPTION su allows one to become the super--user, who has all sortsof marvelous powers. In order for su to do its magic, the user must pass as an argument a password. If the passwordis correct, su will execute the shell with the UID set to that of the super--user. To restore normal UID privileges,type an end--of--file to the super--user shell
I love Unix archeology :)
Wouldn't the password remain in the shell history? Or didn't that exist back then?
It probably wasn't such a concern back in 1971. I mean, even nowadays you still find programs where you can just add a login password to the command line.
Wow, that's terrible for security.
You can do su to change the user in the current shell. Afaik it just defaults to root if no user ist specified. Everytime you run su you actually do su root
That said I always thought that it stands for switch user so intereresting to know that it‘s substitute.
I've heard people call it superuser since before Linux (AIX Unix a long time ago for example).
But substitute user makes sense since you can su to any user (just root is the default).
Usually the root password isn't set at all, and the only way to use rootprivileges is sudo. But OP isn't screwed, they can use a Live CD and chroot
I will also offer some help...
Next time you're "testing things" set up a VM and test there. Don't test things on your primary OS/place you can't just wipe and start over.
That is a great advice. Thanks for the tip my man.
Also setting up a periodic snapshot with tools like timeshift can save your life
Already tried that yesterday and my last back up is three days old. But timeshift needs password and when I entered it. The Timeshoft said that I don't have permision to open it.
right it still require root privileges...
well if you boot from a usb key and you have a btrfs file system, you could manually restore the snapshot. this would bypass the password
any foss vms out there?
KVM/Qemu with Virt-Manager as GUI. There's also Virtualbox, but it's Oracle
If there is docker image for what you need, use docker image.
If not I would recommend systemd-nspawn, it's chroot but can run systemd init, with efforts you can run GUI applications from it too., wiping that is just sudo rm -rf.
I have fucked up somewhat like you in the past and needed to repair my system. In Linux you can boot into runlevel 1, single-user mode, where you are effectively root and can remove the root password, the re-enter one after you boot in the usual runlevel again. See these links: https://www.debuntu.org/how-to-recover-root-password-under-linux-with-single-user-mode/ https://www.debuntu.org/how-to-change-boot-runlevel-with-grub2/ https://www.geeksforgeeks.org/run-levels-linux/
Will try and give you feedback once I'm home. Thanks man.
Runlevels don't exist on systemd. multi-user.target is what you want.
Basically same method Saik0 posred later on. Will try that when I'm home and give my feedback. Thanks.
Are you trying the terminal commands with sudo?
You could also try logging in as root user with the password you used during setup.
Yeah I already tried sudo root via terminal but when I entered the password It said I don't have permision to do that. I can't even change my password to something new in desktop. But I can try setup login once I'm back home.
sudo should only ask for your user password. What do you mean “sudo root”? Do you mean “su”? That would require the root password.
It’s been a little while but he probably didn’t finish setting up sudo so there’s no sudo users file of approved users.
I would just try su.
I’ve had to set it up manually. May depend on the distro, I suppose. su won’t work without the root password.
When I’d set systems up, creating a password for the automatically created root account was one of the first steps in the process after setting up the basics. You could then set other accounts to have root privileges, or set up sudo to allow your personal account access via sudo, but even sudo acts as UID 0. If your setup didn’t do that, or if you set your account name up as UID 0, then you can always boot off of another source and mount the internal hd, right?
It's a matter of distro and the installation process. I must note, I installed Linux dozens of times from 1999-2012 and not as much since then. Back then, while of course one set the root password, it didn't ask about sudo privileges during installation of Debian, Ubuntu or Mandrake. And yes, that's true, you can always boot from a different installation (such as a Live CD) except it is more complex if it is an encrypted filesystem.
Did you try su -l?
Yeah man I tried. But I don't have permision even tho I entered the right password.
You can reinstall the OS without overwriting your home partition or any other data partition. That's always an option.
One of my favorites has always been “sudo passwd”, which works for some reason
I might try that later on.