I set my password to ir****3 when installing Ubuntu, but when I try to use su - postgres on terminal and enter tge same password it shows authentication error: you are not a root user.  How can I fix this?
123863
I've installed PostgreSQL 9.1 and pgadmin3 on Ubuntu Server 13.10.  I configured postgresql.conf with: listen_addresses = '*'  also I configured ph_hba.conf by changed peer connections to md5  Plus I reset the password of postgres by: sudo password postgres  then restarted the service with sudo /etc/init.d/postgresql restart  after that I tried to connect to the default PostgreSQL template database:  sudo -u postgres psql template1   but login failed with this error message:   psql: FATAL:  password authentication failed for user "postgres"   then I tried to login from the pgadmin, which gave me the same error.  I've read here that it might be a password expiry dates bug   but I couldn't solve it coz I cannot login with psql. Does anyone now how to resolve this issue?  EDIT  ph_hba file:    Screenshot:
59930
How do I change from user to superuser (root)? What command do I use in the Terminal to switch to root? I have tried --help but I get lost with all the listed help. I'm looking for a recent download/install so I can use it.
54840
I have a production server. To login to the server I must use a .ppk file.  How to login with Ubuntu Terminal and .ppk file?  I tried this :  ssh -i location/file.ppk username@server-ip   but it is showing an error message.
11355
I'm writing a C Shell program that will be doing su or sudo or ssh. They all want their passwords in console input (the TTY) rather than stdin or the command line.  Does anybody know a solution?  Setting up password-less sudo is not an option.   could be an option, but it's not present on my stripped-down system.
111711
When I boot system in to recovery mode from GRUB menu, I can get in to all powerful root without entering any password, thus insecure.  How I can secure this and ensure that a password is asked every time I attempt to access root in recovery mode?
93990
I installed Ubuntu on my PC. To log in, I use the username and password I created during installation. Does this mean I am a root user? If yes, then how do I become non-root? It looks like non-root user is more secure than admin user.
63549
When I first installed Ubuntu I choose NOT to ask me for a password at login. That was ok for that moment cause it didn't ask me any password at login. But now I want to be asked for a login password. I changed the settings to Not start automatically but it doesn't work. My Ubuntu doesn't ask me password at login. What should I do now?  In the automatic login box (in the user accounts setting window) I have it checked to off (0 or Off), the thing is that my LightDM login screen gives me only a "Start Session" button below my user name, instead of the usual password field.
39768
I know I can become root (super user) via the su command but I have to authorize it after entering the commands. Is there a way I can become root and authorize (with password) in one line
18955
I want to be able to 'su' to a specific user, allowing me to run any command without a password being entered.  For example:  If my login were user1 and the user I want to 'su' to is user2:  I would use the command:  su - user2  but then it prompts me with   Password:
23666
I defined 2 user accounts:   one with admin privilege (with sudo right) => lets call it adminuser. a 2nd one without any privilege => lets call it normaluser and I configure the autologin on this 2nd user normaluser.    So when I open a normaluser session and want to run an application with admin privilege,  I open a terminal Ctrl+Alt+T and:   su adminuser sudo anyapplication ...   It works fine, without having to quit the normaluser session (no need to open a adminuser session).    But what should I do if the application needs to run with a GUI (Graphic User Interface) ? I though about that:  su adminuser gksu anyapplication ...   but I get  ** (gksu:9122): WARNING **: the connexion is closed No protocol specified No protocol specified (gksu:9122): Gtk-WARNING **: cannot open display: :0.0
36110
I'm trying to install the  IDE in my Ubuntu and in the process it's asking for my root password which I don't remember. I know my  user password. How can I recover my root password?
78439
I have installed 12.04 LTS but surprisingly not able to login as root. I have unlock and set the password for root but while login i can not see 'other' option in GUI login where i can put root id and password.  please help me.
37986
Possible Duplicate:          I've just had someone install Ubuntu 12.04. I am not a techie - just a user. I am now asked for a password which I do not have and has never been set. Is there a default one? Otherwise I have to work as a guest all the time... Not so great. I appreciate any help.
95231
This is an update of my earlier question today. That title ("user rights to /usr/share") was unfortunately misleading.  I have a single user system, so I'm a sysadmin by default. Translation: I do not know Linux well enough to do a TeX Live install safely.  I've used TeX Live for several years, but always installed it as sudo. My OS is Ubuntu 19.04. I'd now like to do the TeX Live install as a regular user, because that's what the TeX Live documentation recommends. Let's call that user Bob.  After downloading install-tl-unx.tar.gz and extracting the install-tl script, I start the installation as user, by running: perl install-tl -gui. I get a permissions error saying that Bob cannot install to /usr/local/texlive/2019.  Here's my question. What is the Linux statement, I need to execute as sudo to give me the rights needed to complete this installation?
19264
I am having problems with the su command. I know my password and I am typing it correctly but su indicates authentication failure.  So I checked on the internet and then went into recovery mode and changed my username's password to what I was entering before.  Even now entering the same password on su gives me authentication failure.  Please suggest what am I doing wrong??
94968
For some reason, when I try to run any programs (I am trying to run a rootkit hunter: rkhunter) as root on the command line with sudo like this:  sudo rkhunter   Then I get this message:  You must be the root user to run this program   and then I get these lines:  sudo: error in /etc/sudo.conf, line 0 while loading plugin 'sudoers_policy' sudo: /usr/lib/sudo/sudoers.so must only be writable by owner sudo: fatal error, unable to load plugins   I try typing in just sudo but that comes up with the same three errors as above. Also in /etc/ sudo.conf does not exist.  I cannot run any other programs as root through sudo. It was also strange because I could run as root a day ago. I would like it to work.  Just so you know, I am the only user of this computer, and the administrator, running Lubuntu 14.04.1.
101082
I have done this:  sudo chown -R myname /usr/   and now I can't use the sudo command because of this error:     sudo: must be setuid root   And as I read this means that the owner of this file /usr/bin/sudo is not the root. It's my user now because of the chown on the /usr folder.  On many forums and blogs people suggest to do this as root:  # chown root:root /usr/bin/sudo # chmod 4111 /usr/bin/sudo   ...but the problem with this is that I need to log in as a root, but I can't because If I write su in the terminal the password is wrong (actually I use the password what I added to my user):   $ su Password: su: Authentication failure   So can I get back the sudo command?  Edit: My Ubuntu is under Paralells on my Mac OS X.