Updated 14.04, now in infinite login loop

[deeppow]

Just tried to update 14.04 today and all seemed to go well. But when it rebooted, it is now in an infinite login loop, i.e. it says "guest session" and I give it the password and it repeats the login screen etc. etc. etc.

How can I recover from this problem?

Thank you for your help.

[dino99]

which (x)(k) ubuntu is it ?
from the login dialog, you might see a cog in the right top corner, click on it to select your user instead of the guest, then your password should works (no password needed for a guest)

[deeppow]

which (x)(k) ubuntu is it ?

I have no idea what (x)(k) means. Sorry I'm too much of a newbie.

from the login dialog, you might see a cog in the right top corner, click on it to select your user instead of the guest, then your password should works (no password needed for a guest)

I select me as the user with password, loops back to login. I select guest with no pasword, loops back to login.

[Bashing-om]

deeppow; Hello;

That looping back to the login screen could be the result of a number of faults. Let's explore 2 possibilities.
At the login screen activate a console by key combo ctl+alt+F1.
Can you login here with your username and password ( there is no response to the screen when pass word is entered. enter password blindly and hit the enter key) ?

Post back the results of terminal commands:

ls -al .Xauthority
ls -al .ICEauthority
sudo lshw -C display

and let's see what story gets told

[deeppow]

ls -al .Xauthority
-rw____________

ls -al .ICEauthority
-rw____________

sudo lshw -C display
"display Unclaimed"
"display Unclaimed"

for the 2 monitors I have.

[Bashing-om]

deeppow; Hey;

Look'n more like a graphics driver issue, but ....
Those 2 files, who owns them, and who is grouped ?

sysop@1404mini:~$ ls -al .Xauthority
-rw------- 1 sysop sysop 209 Feb  4 15:15 .Xauthority
sysop@1404mini:~$

sysop@1404mini:~$ ls -al .ICEauthority
-rw------- 1 sysop sysop 1956 May  9 12:38 .ICEauthority
sysop@1404mini:~$

Where in my case I am 'sysop' .

And back to graphics, as no driver is loaded, what is the hardware and we try and match a driver:

lspci -vnn | grep VGA -A 12

and the truth of the matter is ?

[deeppow]

Thanks up and running.

[Bashing-om]

deeppow; Great !

You do good work.

'buntu

it is fixable

[Sebastian_Kindler]

As I encountered the login loop two days ago, I thought I should share. (This is a repost, as this thread's title is more fitting than the other.)

Searching for a solution in other threads, you will find there is one dominant solution: access privileges for both of the files, .Xauthority and .IDEauthority.

Bashing-om's solution is spot-on. However, it might not solve the issue for everybody. (Sorry, if the rest of this post seems unnecessarily detailed but I had to look for this information in so many places that I thought, someone might appreciate to have it all in one place.)


How to find whether or not you "own" those .*authority files?


Login as Guest, which you have probably done anyway to use the internet.


Open a login terminal with Ctrl + Alt + F2, or alternatively, + F3, + F4, and so on until F6. (You should be able to do that without logging in as Guest as well.)


Ctrl + Alt + F7 brings you back to your "Desktop", so you can switch back and forth to continue reading.


(I will use ASUS-S400CA as an example.)

Ubuntu 14.04.2 ASUS-S400CA tty2


ASUS-S400CA login:

Type in your username. (Your username is the nickname you chose at installation, not your full name you may see on your actual login screen.)


Then type in your password.

Ubuntu 14.04.2 ASUS-S400CA tty2


ASUS-S400CA login: yourusername


Password:

You should now see:

yourusername@ASUS-S400CA:~$

If your login loop is caused by missing access privileges for the files mentioned earlier, this code should do:

ls  -ld  ~/.*authority

If you then get

-rw------- 1 root root 2015 May  24 12:38 .ICEauthority


-rw------- 1 root root 2015 May  24 12:38 .Xauthority

instead of

-rw------- 1 yourusername yourusername 2015 May  24 12:38 .ICEauthority


-rw------- 1 yourusername yourusername 2015 May  24 12:38 .Xauthority

you have to use the chown command to get back your access privileges:

sudo  chown  yourusername:yourusername  ~/.Xauthority

and if necessary the same for .IDEauthority. Note that you will have to verify the result again with the ls command. No error message is a good sign, though.




Your shell does not recognize any of the commands you type in?


This could be the main cause for the login loop as login itself is just a command.



How to use commands under these circumstances?


The shell gives you two pieces of information: First, the command is not accessible. Second, it is found in, e.g.

/usr/bin

In this case the above mentioned code looks - depending on where "the executable" of the command is located in your system - something like this:

/usr/bin/ls   -ld   ~/.*authority


/usr/bin/sudo  /bin/chown   yourusername:yourusername   ~/.Xauthority


/usr/bin/sudo  /bin/chown   yourusername:yourusername   ~/.IDEauthority

The reason why your command prompt (shell, Terminal, command line) recognizes and executes commands - including the login command - is, because the paths to their directories - like /usr/bin, /bin, /sbin and so on - are all saved in a file. There they are given as the value to a variable called PATH. (For easy to understand explanations on Linux terms check out linfo.org. In this case linfo.org/path_env_var.html)




To check, which paths are saved in PATH, type

echo $PATH

or its equivalent command with directory structure.


It will probably give you something like

/usr/local

However it should look like:

/usr/bin:/usr/sbin:/bin:/sbin:/usr/local/:/usr/local/bin:/usr/local/sbin

The different directories between the colons can be arranged in any order.




To save those temporarily, and be able to use commands, type

export PATH=$PATH:/usr/bin:/usr/sbin:/bin:/sbin:/usr/local/:/usr/local/bin:/usr/local/sbin

To make those changes permanently, you have to save it in the respective file, where your PATH variable is defined.


Depending on your type of shell (bash etc.), this could be a different file, and there are certain (new) conventions about in which (configuration) file to exactly save those paths to your commands. (unix.stackexchange.com/questions/88201/whats-the-best-distro-shell-agnostic-way-to-set-environment-variables)


In your home directory ~ , which is equivalent to /home/yourusername, there should be a file called .profile. If you temporarily saved your directories to your commands you can open that file by typing

sudo gedit ~/.profile

This opens the file with the respective text editor gedit. (Just in case you do not have gedit for some reason, use the aptitude or apt-get command in combination with sudo and install gedit or any text editor you prefer: sudo apt-get install gedit .)


At the end of that file you probably find something like:


# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/bin" ] ; then
PATH="$HOME/bin:$PATH"
fi


PATH=usr/local




However, PATH should be defined just as described above. Simply, add the other directories:


PATH=/usr/local:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin


save the file, reboot your system, and you should (hopefully) be good to go.