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artistde
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Joined: 04/25/2018

I changed the user to no password on log in on Users group, now the only way I can get in on my laptop is with guest log in.

I am using Trisquel 8, any help with this problem would be appreciated.

loldier
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Joined: 02/17/2016

You'll have to use Grub menu recovery mode to gain root privileges. Select Grub's entry "Advanced options" at boot.

Then select 'drop to root prompt' and proceed to change your account's password. If the drive is mounted read only, mount root partition with proper permissions 'mount -o remount,rw /' (without quotes).

# passwd your_account_name

With full disk encryption enabled and single OS boot, the Grub menu won't show automatically (I had difficulty evoking Grub with shift or esc at the right time); edit /etc/default/grub --> comment out (prepend with #) line 'GRUB_HIDDEN_TIMEOUT=0'. After changes to Grub, reload grub configuration 'sudo update-grub'.

https://askubuntu.com/questions/16042/how-to-get-to-the-grub-menu-at-boot-time

https://askubuntu.com/questions/826282/full-disk-encryption-how-to-boot-in-as-runlevel-1

https://wiki.ubuntu.com/RecoveryMode

##EDIT##

I created a password-less account 'test' which could not be logged in. I managed to create a new password for user 'test' using recovery mode and root prompt. I had to mount the drive read/write, otherwise "authentication manipulation error" would occur.

##EDIT 2##
'Rescue mode' changed to 'recovery mode'.

artistde
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Joined: 04/25/2018

Thanks for your replies, but I#m new to using GNU/Linux, when it boots up it goes to sign in and the only way I can sign in is on guest which all is temporary. Mate won't change anything because it is guest only.

artistde
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Joined: 04/25/2018

You'll have to use Grub boot rescue mode to gain root privileges. Select Grub's entry "Advanced" at boot.

No idea how to get to that above?

loldier
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Joined: 02/17/2016

Reboot and press shift or esc before Trisquel loads. Try to press it multiple times in a sequence after BIOS. If that doesn't help, press and hold shift to get access to Grub menu. It can be tricky sometimes.

It's explained here in this link. If shift (left shift) fails to work, try with esc (escape).

https://askubuntu.com/questions/16042/how-to-get-to-the-grub-menu-at-boot-time

There's a tutorial video on the subject on YT. Watch that, I'm sure you'll get the hang of it.

https://youtu.be/m3rbpR9uuHA

artistde
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Joined: 04/25/2018

there is no boot rescue mode to choose

loldier
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Joined: 02/17/2016

Every GNU/Linux system needs a boot loader (Grub is a boot loader).

Grub's there and it has a rescue option in its menu. You'll just have to remain calm and keep your cool; press esc/shift at the right time. Try multiple times in a sequence. If you fail, try again. Eventually, you'll succeed.

artistde
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Joined: 04/25/2018

I have tried it with every button, nothing brings up what it shows on the Utube video. I am using Trisquel 8.

Magic Banana

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I am a translator!

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Joined: 07/24/2010

If you cannot get a root shell through GRUB, here is an alternative:

  1. Boot a GNU/Linux Live system such the Trisquel 8 live system: https://trisquel.info/en/wiki/starting-installable-live-system
  2. Open a terminal;
  3. Somehow identify the root partition of the installed system (for instance using the 'lsblk' command if you have a rough idea of its size, probably around 15 GB), the partition whose filesystem is mounted at /;
  4. Let us say that partition is /dev/sdaX (where X is a number); mount its filesystem at /mnt:$ sudo mount /dev/sdaX /mnt
  5. Make /mnt the root of the file hierarchy:$ sudo chroot /mnt
  6. You now have the equivalent of a root terminal in the installed system. To change the password of a user whose login is "artistde":# passwd artistde

If you only remember the user name (written on the graphical login screen), 'grep' it in /etc/passwd (substitute "user name" with the actual user name or part of it):
# grep 'user name' /etc/passwd
The login is before the first ":".

artistde
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Joined: 04/25/2018

i GUESS ALL i CAN DO IS THROW THE THING IN THE TRASH

artistde
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Joined: 04/25/2018

It seems to have worked, what do I do next it is still on the mate screen what do I do now?

loldier
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Joined: 02/17/2016

Did you set the password?

# passwd your_user_name

artistde
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Joined: 04/25/2018

How do I change back to a password on log in?

loldier
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Joined: 02/17/2016

What do you mean "change back"? You can't change back in GUI (graphically). You must have set your password. If you did that in Grub recovery, then at the login screen, type your password and log in.

Refer to post #13:

https://trisquel.info/en/forum/users-group#comment-134976

--Grub menu access shift or escape at boot
--Advanced options --> recovery mode --> drop to root shell prompt
--mount -o remount,rw /
--passwd user_name
--reboot

When you select "drop to root shell prompt", you get a small command line at the bottom. That's where you have to press enter and mount the drive read/write.

You see those little thumbnails? Click on them and they pop out as larger pictures.

artistde
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Joined: 04/25/2018

how do I write the exact command to have log in go back to PW?

loldier
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Joined: 02/17/2016

--Grub menu access shift or escape at boot
--Advanced options --> recovery mode --> drop to root shell prompt
--mount -o remount,rw /
--passwd user_name
--reboot

Exact command mount:

'mount -o remount,rw /' (without quotes)

Set password:

'passwd your_user_name' (without quotes & type your own user name)

It will ask for your new UNIX password, give it (won't echo = show). That's done twice.

Then type 'reboot' (without quotes).

artistde
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Joined: 04/25/2018

Do I leave the Screen on that let me log in under tty1?

loldier
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Joined: 02/17/2016

Are you in Grub or TTY? TTY is completely different.

You leave Grub recovery by typing 'reboot' (without quotes). Press enter after every command.

The machine should reboot. Login screen should appear.

artistde
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Joined: 04/25/2018

I can Log in to my name on the tty1 screen but on the login page I had changed the name to the person who was buying the laptop with no log in that is when all the problems started. is there a way to change the name to peter on tty1?

loldier
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Joined: 02/17/2016

Create a new account

# adduser peter

or

$ sudo adduser peter

Note: '#' means root ($ = user)

artistde
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Joined: 04/25/2018

Also am I able to leave the tty1 screen and go to the computer without logging in again? since the log in name is not mine on the log in page?

loldier
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Joined: 02/17/2016

You should see all the account names on the login screen. If you want to leave TTY1 and go to X, press ctrl+alt+F7.

If you are logged in at TTY1, log out type 'exit' (without quotes).

artistde
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Joined: 04/25/2018

I input #adduser peter there was no reaction? is that OK?

loldier
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Joined: 02/17/2016

You don't type the hashtag.

just type 'sudo adduser peter' (without quotes) if non-root

# = root prompt
$ = user prompt

eg.

# adduser peter
$ sudo adduser peter

artistde
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Joined: 04/25/2018

Peter does not show up on the login as new user

artistde
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Joined: 04/25/2018

would not let me add peter says already exists, true but not in log in, I added Josef-Peter with pw but when I log in it does the same as before it returns to log in?

loldier
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Joined: 02/17/2016

If you added the new user correctly, this is what you see:

myaccount@trisquel:~$ sudo adduser newuser
[sudo] password for myaccount:
Adding user `newuser' ...
Adding new group `newuser' (1002) ...
Adding new user `newuser' (1002) with group `newuser' ...
Creating home directory `/home/newuser' ...
Copying files from `/etc/skel' ...
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
Changing the user information for newuser
Enter the new value, or press ENTER for the default
Full Name []:
Room Number []:
Work Phone []:
Home Phone []:
Other []:
Is the information correct? [Y/n] y
myaccount@trisquel:~$

After this the new user 'newuser' can be selected at the login screen. It shows up.

artistde
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Joined: 04/25/2018

YES THAT IS WHAT I SAW. THANKS FOR ALL YOUR HELP, SAVED MY LAPTOP.

artistde
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Joined: 04/25/2018

I would like to thank everyone for your help, It is working again. would not been able to do this without everyone involved help.

THANKS AGAIN

loldier
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Joined: 02/17/2016

For those concerned that Grub lets drop to root shell prompt so easily, there's a way to generate a password for Grub.

https://askubuntu.com/questions/656206/how-to-password-protect-grub-menu

Generate hash:

$ grub-mkpasswd-pbkdf2

Edit Grub configuration:

$ sudo nano /etc/grub.d/40_custom

Type this and save, filling in your user name and the hash just generated by the first command:

set superusers="username"
password_pbkdf2 username hash

Magic Banana

I am a member!

I am a translator!

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Joined: 07/24/2010

It is almost always useless, according to GRUB's developers:

By default, the boot loader interface is accessible to anyone with physical access to the console: anyone can select and edit any menu entry, and anyone can get direct access to a GRUB shell prompt. For most systems, this is reasonable since anyone with direct physical access has a variety of other ways to gain full access, and requiring authentication at the boot loader level would only serve to make it difficult to recover broken systems.
However, in some environments, such as kiosks, it may be appropriate to lock down the boot loader to require authentication before performing certain operations.

https://www.gnu.org/software/grub/manual/grub/html_node/Authentication-and-authorisation.html#Authentication-and-authorisation

The most common "other way to gain full access" is through a live system, as I suggested above. Encrypting user data is real security. Getting a root terminal will not decrypt those data.

loldier
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Joined: 02/17/2016

Yes, my drive is encrypted. Grub console asks for decryption key before anything can be done with it. Trisquel 8 Grub has no password set, contrary to Trisquel 7 (which was stored in plaintext).*

However, MBanana's admonishment has already been echoed in the link I provided.

"Grub allows you to password protect its config and console, as well as individual operating system entries. Please note that this will not stop dedicated individuals, especially the ones that know what they are doing. But I assume you know that. Lets get started."

Further reading on "lost password":
https://aplawrence.com/Linux/lostlinuxpassword.html

*I wonder why Ruben relented. He used to be so adamant about it.

loldier
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Joined: 02/17/2016

Indeed, an encrypted disk cannot be accessed without a valid password even if the computer allows booting from a USB live system.

All disks should be encrypted automatically and by default.

encrypted_data_unlock.png
zonyon
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Joined: 10/10/2018

I have the same problem. I can only access my laptop on guess session, I have lost my administrator privilege.
I have pressed all the keys (Shift, Esc, Spacebar ...) nothing works for me. I have read all the links posted on that thread and tried multiple time over and over again, nothing works. I am also new to GNU/Linux, how can someone help me, please?

Magic Banana

I am a member!

I am a translator!

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Joined: 07/24/2010

If you cannot boot into a root terminal, then try to get one from a live system: https://trisquel.info/forum/users-group#comment-134959

zonyon
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Joined: 10/10/2018

Thanks for replying, but when I tried the first command it spits out this denial message "Operation not permitted". It gives me that message because I need administrative approval, but I can access the computer only on Guest Session.