Questions about authenticating wireless connections, SSH keys, or passwords in Ubuntu.

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139
votes
12answers
168k views

How can I set up password-less SSH login?

I want to be able to login to a remote via ssh without having to enter the password all the time. How do I set it up? Is a different command required to execute a password-less session?
113
votes
6answers
82k views

Why am I getting authentication errors for packages from an Ubuntu repository?

I'm experimenting with VPNs, so I wanted to install pptpd. john@desktop:~$ sudo apt-get install pptpd [sudo] password for john: <snip> The following extra packages will be installed: bcrelay ...
104
votes
3answers
102k views

How do I deal with “unauthenticated sources” errors in the Software Center?

Any install that I'm trying through the Software Center is telling me: Requires installation of untrusted packages: The action would require the installation of packages from not authenticated ...
52
votes
2answers
63k views

How can I allow SSH password authentication from only certain IP addresses?

I'd like to allow SSH password authentication from only a certain subnet. I see the option to disallow it globally in /etc/ssh/sshd_config: # Change to no to disable tunnelled clear text passwords #...
52
votes
3answers
6k views

How can I use a passcode generator for authentication for remote logins?

I would like to strengthen the authentication of my SSH logins by adding another factor: a passcode generator device, or a passcode generation application on my mobile phone. The only obvious options ...
33
votes
2answers
28k views

How can multiple private keys be used with ssh?

I was able to setup ssh to use private/public key authentication. Now I am able to do ssh user@server1 And it logs on with the private key. Now I want to connect to another server and use a ...
31
votes
1answer
7k views

How can I use face-recognition to login?

I am using Ubuntu 12.04 64-bit. I am looking for a facial recognition program that I could use to log in to my account. I have heard of Pam Face Recognition, but there does not appear to be a package ...
28
votes
6answers
68k views

How to run an application using sudo without a password?

... but still be required for applications that need admin privilegies? In order to allow the following: $ apache2ctl restart httpd not running, trying to start (13)Permission denied: make_sock: ...
26
votes
3answers
16k views

nslookup finds ip, but ping doesnt

I know this looks like all the other "can ping via ip but not dns" questions, but those didnt really help me at all. Also, having hosts files in all machines is not doable as this server will ...
26
votes
1answer
1k views

How to know if a authenticate box is real or fake?

For example, someone creates a fake Authenticate dialog to get my root password. How to know if it is real or fake?
23
votes
6answers
47k views

“Software can't be installed or removed because the authentication service is not available. ”

I have 12.10 ubuntu and when I try to remove / install programs I get notification : Software can't be installed or removed because the authentication service is not available. (org....
20
votes
14answers
113k views

Trying to do ssh authentication with key files: server refused our key

I'm trying to setup ssh authentication with key files in stead of username/password. The client is a Windows box running PuTTY and the server is a Ubuntu 12.04 LTS server. I downloaded puttygen.exe ...
19
votes
9answers
16k views

Access Prompt keeps asking for GMail password

A pop up keeping appearing in Ubuntu (running 12.10), asking for the password to my gmail account. The icon has a silver shield, and it is labeled Access Prompt. The actual window has an image of ...
17
votes
1answer
11k views

Error authenticating some packages while upgrade

When I try to upgrade my ubuntu 13.04 to 13.10, it gives the following error: It was not possible to authenticate some packages. This may be a transient network problem. You may want to try again ...
15
votes
5answers
29k views

Can't complete dropbox installation from behind proxy

Problem: My PC on campus sits behind a proxy (requiring authentication) and I can't setup Dropbox. I am convinced that this is a proxy issue as I can't setup Ubuntu one either (but I don't use Ubuntu ...
15
votes
8answers
20k views

ssh no longer allows public key authentication

My machine recently stopped accepting incoming public key authentication. I have an ubuntu 11.04 desktop that I ssh into from a windows machine. I use putty with pageant. I am able to connect but ...
14
votes
5answers
12k views

I deleted the “/etc/passwd” file and cannot log in

I was trying to change my username and also my home directory (/home/username) and my system started to crash. I deleted the passwd file but I had a backup named passwd_bkp. I tried to rename this ...
11
votes
2answers
4k views

What is the least insecure way to store a password that is used by a script?

I have a Bash script that automatically authenticates with a service using my username and password. The credentials are currently stored as plain text within the script. What precautions should I ...
11
votes
3answers
5k views

Security warning from Facebook in Chromium

I am terrified. Every ten minutes Chromium pops up with a tab stating: Success SECURITY WARNING: Please treat the URL above as you would your password and do not share it with anyone. Very ...
10
votes
1answer
7k views

Error Password: chsh: PAM: Authentication failure when try to install Oh my zsh

I try to install Oh my zsh. After install zsh (sudo apt-get update && sudo apt-get install -y zsh) Then I install sudo apt-get install -y curl then install git. the problems occurs ...
10
votes
5answers
10k views

Use different username on CUPS remote printing

I'm using CUPS to print on an enterprise network. The job gets submitted fine, but I need to submit it as another username. Now I'm jon but I need to send it as say jonallard. On the command line, ...
8
votes
1answer
63k views

Can't SSH in as root

I'm using the default installation of openssh-server for my Ubuntu 14.04 server. I can connect through the console as root like normal, with my username and password. When I try to SSH with the same ...
8
votes
3answers
20k views

How to use “apt-get” via “Http-proxy” like this?

I'm trying to use apt-get command on a network that uses a proxy, like this: We use 10.114.7.7 on port 80 as Http-proxy, and after that an authentication window comes up, asking for user name and ...
8
votes
2answers
3k views

I get Authentication is needed to run `/usr/bin/dropbox' as the super user

in a system popup window on startup. Anyway to avoid this? fwiw I authenticate ok with my pw. I think this may have started after my recent upgrade from Ubuntu 12 -> 13
8
votes
4answers
4k views

Stop asking for authentication to mount USB stick

My Ubuntu 14.04 is asking for my password to mount or unmount an USB stick. How can I change it, so that the mount is automatic and no password input is required ? This is about mounting arbitrary ...
8
votes
0answers
256 views

How to move keys to “Login” in seahorse? [duplicate]

Possible Duplicate: Is there a way to move passwords from “Default” to “Login” in seahorse? I want to move a few passwords into "login" in Seahorse, so that I will ...
7
votes
4answers
17k views

Why can't I access super-user mode with su? [duplicate]

I just have managed to install Lubuntu 12.04. Now I want to do some things in the terminal like installing and configuring the Apache and a Lamp-system among other things. I come from Open SUSE world ...
7
votes
2answers
11k views

Wifi only accepts passwords of 5 or 13 characters

Installed Ubuntu 13.04 and when attempting to connecting to a home wifi network, the connect button is only click-able with passwords of 5 or 13 characters. Is there a fix?
7
votes
2answers
62k views

Proxy authentication with terminal Ubuntu 14.04

I would like to access the internet to update files etc. from the terminal on a secured proxy network. I've already tried the following: Adding to /etc/apt/apt.conf, /etc/apt/apt.conf.d/01proxy, /...
7
votes
2answers
1k views

Authentication required to modify a printer- what's the password?

I have 12.04 and have 2 printers installed, both wirelessly over my personal network, no printer sharing. When I try to modify the printers I get a window asking for authentication (username and ...
7
votes
3answers
4k views

Install packages without root permissions

Would it be possible to install packages without admin rights(sudo?) on Ubuntu? It doesn't have to be system-wide, maybe a private installation within /home. I want this because I'd like to setup my ...
6
votes
4answers
12k views

Retrieve Windows 8 Product Key from mainboard

My new laptop came preinstalled with Windows 8. Naively, as I am, I just formatted the harddrive and installed fine old Ubuntu. Now I want to install Windows 8 for dual boot again, but I have no DVD ...
6
votes
4answers
28k views

Ubuntu 12.04 network printing through Windows Samba server

I have to print through a Samba server sharing an HP printer. After upgrading to 12.04 I'm no longer able to get it to work. The printer is shared through a samba server and I need to provide logon ...
6
votes
3answers
3k views

gksudo with cool GNOME Shell integration

What's the command for executing this "gksudo" (or whatever it is) window from Alt+F2?
6
votes
1answer
383 views

How do you Make Ubuntu One re-authenticate?

I was trying to restart syncing with Ubuntu One because it was not syncing my music folder. However, I accidently deleted my computer from the sync list: (Ubuntu One.com > Account > View the ...
6
votes
2answers
3k views

USB drive Login token system?

Is it possible to have a USB drive function as a login token? IE: I turn on my computer, plug the USB drive into my system and the system recognises it and logs me in? Likewise, logs me out should ...
6
votes
2answers
2k views

Unauthenticated software sources

My Lucid (10.04) installation recently started warning me that the updated packages were unauthenticated. For instance, if I open Update Manager and click the "Install Updates" button, it warns me ...
6
votes
1answer
4k views

Could not load host key: /etc/ssh/ssh_host_ed25519_key in /var/log/auth.log

I have an Ubuntu 14.04 instance running on AWS. I was browsing the auth logs (/var/log/auth.log*), and noticed the following line appearing: Could not load host key: /etc/ssh/ssh_host_ed25519_key ...
6
votes
1answer
335 views

OAuth/Authenticating user for Unity Lenses

Trying to create a lens that would touch a web service that requires oauth authentication. And a search here, netted me this: https://wiki.ubuntu.com/Unity/Lenses I was using this tutorial to ...
6
votes
2answers
32k views

How to use Google Authenticator with OpenVPN server on Ubuntu 12.04

I have a working OpenVPN system on Ubuntu 12.04 and I'd like to add Google Authenticator for extra security. This is my current openvpn config: dev tun proto udp port 1096 ca ubuserv04-ca.crt cert ...
6
votes
1answer
2k views

UbuntuOne for Windows does not work - I got “Problem opening the ping_url” error

When I try to login to existing account I got "Problem opening the ping_url" error.
6
votes
1answer
2k views

Stop Ubuntu asking for password to mount second drive

Whenever I turn on my machine and browse to the second hard disk in nautilus it asks me to authenticate to mount the drive. I can find guides on how to turn on this behavior, but not to de-activate ...
6
votes
1answer
3k views

Auth failed error on windows 7 ultimate

after installing ubuntu one on windows 7 ultimate, when i try to log in, Ubuntu gives me back the message :The authentication failed. Oh, it's OK. Perhaps I've forgotten the pass. So i clicked I've ...
6
votes
2answers
701 views

How do I configure a fingerprint scanner?

I have a HP dv6-3079tx. One feature I like about it is the fingerprint scanner, Is there a utility out there that will allow me to swipe my finger whenever I am required to enter my password?
6
votes
0answers
112 views

16.04 server: enabling LDAP authentication causes systemd-logind to fail

I'm stumped here, sorry if I'm missing something obvious. I had a 16.04 server authenticating against LDAP that stopped working last time I ran updates, and I built a clean 16.04 server from scratch, ...
5
votes
3answers
6k views

Is there a way to lock my browser with a password?

It would be OK if it was only with my login password, but I would like to lock both midori and Firefox so that they cannot be used without entering a password. I'm running 12.04.
5
votes
1answer
5k views

how to setup two factor authentication in Ubuntu for Ubuntu users using Google authenticator?

How to setup two factor authentication in Ubuntu for Ubuntu users using Google authenticator (It can also be setup for non Google accounts)?
5
votes
2answers
5k views

OpenSSH Two Factor Authentication

I'm using Ubuntu Server 13.04 and want to use OpenSSH for sftp. I have everything set up and the only thing not working is the Two Factor Authentication. Currently it asks for a password or the public ...
5
votes
1answer
31k views

connect to openvpn using username and password

Is it possible to connect to an openvpn server using a username and password. I read that you need a config file on ubuntu, but I don't have a config file. How can I connect to my openvpn server ...
5
votes
1answer
3k views

Login on local terminal without password

I have a virtual guest of Ubuntu on a KVM Machine, I've setup the machine so I can type virsh console and be dropped into a console. I realise the security considerations here, but is it possible to ...