SSH (Secure SHell) is a protocol for running commands on a remote computer.

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Permanent background ssh connection to create reverse tunnel: what is correct way?

Related question: initiate ssh connection from server to client Answer from there helped me a lot, this command does what I need: ssh -R 2225:localhost:22 loginOfServerWithPublicIP@publicIP So I ...
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6answers
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SSH automatic remote back ups

I have two machines, A and B. Machine A can ssh into B. A has a lot of free space. B's data is in a sort of risky situation. How do I back up all of B's data to A automatically. It does not have to ...
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2answers
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SSH key-based authentication: known_hosts vs authorized_keys

I read about setting up ssh keys in Linux and have some questions. Correct me if I'm wrong… Let's say host tr-lgto wants to connect to host tr-mdm using ssh. If we want to be sure that it's the real ...
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3answers
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How can I make a user able to log in with ssh keys but not with a password?

I would like to create a user and have no password. As in you cant log in with a password. I want to add keys to its authorized_keys by using root. This is for my automated backup system.
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2answers
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How do I force a user to change a password at the first time login using ssh?

I'm trying to force a newly created user to change a password at the first time login using ssh. For security reasons I want to give him a secure password until he logs in for the first time. I did ...
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4answers
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Stopping output from a program run in SSH session NOW

Problem I execute command that outputs LOTS of information through SSH. For example, I foolishly add debug information inside a loop that executes million times, or just run cat /dev/urandom for ...
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4answers
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Can I transfer files using SSH?

I am using PuTTY on Windows 7 to SSH to my school computer lab. Can I transfer files from my Windows machine to my user on the school machines using SSH?
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3answers
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How can I track who SSH'es into my linux machine?

I'm running Ubuntu 10.04. Is there a way I can get a daily report of who has logged onto the box, what time, and even - this may be asking too much - a report of the commands they used? This is a ...
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1answer
712 views

How to execute an arbitrary simple command over ssh without knowing the login shell of the remote user?

ssh has an annoying feature in that when you run: ssh user@host cmd and "here's" "one arg" Instead of running that cmd with its arguments on host, it concatenates that cmd and arguments with spaces ...
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4answers
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Advice for managing SSH keys

What is the best practice you have found for managing lots of SSH keypairs? I use SSH to connect to several systems, both at home and at work. I currently have a fairly small, manageable collection ...
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2answers
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How to edit authorized_keys?

What is the best method for editing the /root/.ssh/authorized_keys file? I mean if I need to append a new key to my authorized_keys file, than what are the best methods to do that?
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3answers
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sudo over ssh: no tty present and no askpass program specified

I keep getting this error and have tried several ways discussed online to fix this and none are working for me. I have setup SSH keys so when I run 'ssh newton@host.com' it automatically logs me in, I ...
12
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1answer
7k views

Remote desktop over SSH reverse tunnel to replace TeamViewer

I want to open a remote desktop session from my laptop to desktop over my SSH (reverse) tunnel. That should be simple (or at least doable), right? Until now I've been using Team Viewer to log in to ...
12
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4answers
906 views

Groups differ from the local ones when logging in remotely

We store our users in LDAP, alongside some groups that have meaning across different systems (organizational roles including wheel). There are also groups local to workstations, e.g. audio or video ...
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5answers
30k views

Disable user shell for security reasons

We have several user accounts that we create for automated tasks that require fine-grained permissions, such as file transfer across systems, monitoring, etc. How do we lock down these user accounts ...
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5answers
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What is the right file permission for a .pem file to SSH and SCP

I have tried to SSH into my AWS ubuntu server and copy the directory to my local machine. Throughout the process I experience different file permission errors (noted below). Is there one specific ...
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2answers
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Understanding SSH tunnels

I have linux (Ubuntu) server which I have root access to through ssh (port 22) only. On that server there is a MySQL database listening on port 3306. Is it possible to use putty (on my machine) and ...
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4answers
338 views

Is my SSH key paired with me as a human, or with my user account on one machine?

In the past few days, I have been trying to acquaint myself with SSH, and I hope that I've understood it. One question remains, however -- is my key associated with me (as the user) or my user ...
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5answers
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Can a linux user change their password without knowing the current password?

I'm setting up a few ubuntu boxes, and using opscode's chef as a configuration tool. It would be fairly easy to install public keys for each user on each of these servers, and disable password ...
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2answers
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How do I sftp to a server if the username contains @ symbol

I have to sftp to a server to a specific port but the username contains the @ symbol. suppose the user is "user@domain.com" and the ftp server is just "domain.com" I will end with sftp -oPort:8777 ...
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5answers
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Use socks proxy for commands in terminal

I connect to a remote ssh server by running this command: ssh -D 12345 bob@myserver.com This creates a socks proxy that I can use with Firefox to bypass censorship in my country. However, I can't ...
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2answers
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Detach/reattach an application run on X over SSH?

I have a development server that I leave running all the time, and a development laptop that I turn off/on everyday. I have a GUI application on the server that I'd like to run over SSH -X, and I'd ...
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2answers
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ssh and character encoding

When I ssh into my VPS, I have irssi running in screen. When someone sends a unicode character (such as © or €), irssi displays garbage when I use it via the screen in a ssh session. If I connect to ...
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7answers
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Why does my Python background process end when SSH session is terminated?

I have a bash script that starts up a python3 script (let's call it startup.sh), with the key line: nohup python3 -u <script> & When I ssh in directly and call this script, the python ...
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4answers
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How to copy with SCP between two servers using key auth?

I can log in via SSH using key authentication to SERVER1 and SERVER2. However, I can't copy files between the two servers. Why? How can I copy between them? (the data that I have to copy is bigger ...
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3answers
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Why does my X11 forwarding attempt fail with “connect /tmp/.X11-unix/X0: No such file or directory”?

On my local machine, I run: ssh -X me@remotemachine.com (For completeness, I have also tested all of the following using -Y with identical results). As expected, this accesses remotemachine.com ...
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3answers
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GNU screen freezes trying to reattach

I have several long-running GNU screen sessions. I ssh to the box they're running on and run screen -d -r foo to detach them if they're connected anywhere else, and then attach them in my current ...
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2answers
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How to pipe a remote file to stdout over scp or sftp?

Using ssh, it is easy to print the contents of a file using ssh host 'cat file.txt' When ssh is disabled, and only SFTP is enabled, running the previous command gives the following error: ...
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3answers
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Adding a user who can only execute scripts remotely

I would like to create a user who can only do one thing: via ssh specify a script ( and commandline arguments to the script ) that resides in one particular folder ( for the purposes of this question ...
11
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1answer
12k views

Foreign characters won't display in SSH

I'm having some problems with using ssh and a remote server (which I do not have admin access to) - Specifically, there are a couple of folders on there with Korean and Cyrillic text. When I display ...
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3answers
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How to open a port early in boot process to unlock LUKS via SSH

I have a fully encrypted server running Debian 7 and have set up dropbear and busybox to unlock the LUKS container via SSH (as described in this tutorial and in this U&L answer). Unfortunately, ...
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1answer
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How to use ssh-agent with multiple (valid) keys and yet choose which one to use?

Let's say there are two keys A and B, both of which are valid for user@host public key authentication. Since authorized_keys is configured for different behaviour depending on the key, ~/.ssh/config ...
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1answer
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Meaning of “Connection closed by xxx [preauth]” in sshd logs

We have a Windows batch script, which connects automatically to a linux server via PLINK (putty). There is NO public private key authentication, the user and the password are in the script. On our ...
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2answers
438 views

A consistent and safe approach to passwordless accounts with SSH

I must admit that I like servers without passwords in some cases. A typical server is vulnerable to anyone who has physical access to it. So in some cases it is practical to lock it physically and ...
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4answers
2k views

How do I trigger autocomplete without a tab key?

I'm ssh-ing to my machine using my iPhone with an app called ServerAuditior. It doesn't have tab key. See screenshot. How do I trigger autocomplete without the tab key? I don't want to type a lot of ...
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3answers
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Shell Script for logging into a ssh server

I tried writing a shell script which can do automatic login into a ssh server using password which is mentioned in the script. I have written the following code: set timeout 30 /usr/bin/ssh -p 8484 ...
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3answers
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ssh port forward to access my home machine from anywhere

http://serverfault.com/questions/303937/how-to-make-freebsd-box-accessible-from-internet I want to understand this whole process of port forwarding. I read so many things but failing to understand ...
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4answers
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rsync without prompt for password

I need to execute rsync, without it prompting me for password. I've seen in rsync manpage that it doesn't allow specifying the password as command line argument. But I noticed that it allows ...
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2answers
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How to temporarily switch from ssh to my local shell?

I'm using cygwin. and use it with ssh to login into a ubuntu server. sometimes, I want to switch back to my cygwin and then quickly switch to ubuntu shell. How to do this?
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3answers
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Get ssh server key fingerprint

Is there a way to programmatically obtain a SSH server key fingerprint without authenticating to it? I'm trying ssh -v user@host false 2>&1 | grep "Server host key", but this hangs waiting for ...
10
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2answers
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How to configure SVN/SSH with SSH on non standard port?

I have configured SSH to be on port 20000. When I try: svn co svn+ssh://server.com:20000/home/svn/proj1 proj1 --username jm I get svn: To better debug SSH connection problems, remove the -q ...
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1answer
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How to wget a file to a remote machine over SSH?

I'd like to basically pipe a wget command to a file on a remote server over SSH. How can I do this? I know I could simply ssh into the server and have it download the file, but I'd much rather use the ...
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5answers
748 views

How can I configure such that I can always SSH to my system over the internet on a dynamic IP?

Basically I want to be able to do something like teamviewer, where regardless of what the network configuration is, as long as both my ssh server (Machine A) and ssh client (Machine B) have internet ...
10
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5answers
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ssh returns message “X11 forwarding request failed on channel 1”

When I ssh into a remote server that's not running any type of X11 desktop environment I get the following message. $ ssh user@server X11 forwarding request failed $ ssh user@server ls X11 ...
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4answers
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How can I set default settings for htop?

Occasionally, I need to check resources on several machines throughout our data-centers for consolidation recommendations and the like. I prefer htop, mostly because of the interactive feel and the ...
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3answers
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Can I connect to or view abandoned ssh sessions?

I have a virtual instance of redhat running that I can ssh to from any host on the corporate network. My ssh session was dropped while running some scripts that may or not have caused me to ...
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5answers
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ssh prompts for password despite ssh-copy-id

I've been using public key authentication on a remote server for some time now for remote shell use as well as for sshfs mounts. After forcing a umount of my sshfs directory, I noticed that ssh began ...
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3answers
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Kill process spawned by ssh when ssh dies

This is a question that has been addressed several times, not only here, but also in other sites of the stack exchange network (e.g. ...
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3answers
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How can I lock my own account from remote ssh login with password?

I don't want to disable remote login with password altogether, but I want to make it so that my account is only accessible with key pair authentication (there are other users who wants to use ...
10
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1answer
7k views

ssh-agent forwarding for a Vagrant VM

I'm currently looking at setting up a Vagrant environment on my Mac machine, so that I can run vagrant up and it will then install rbenv and ruby and all I need. Then I have a Bash script that will ...