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

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How to execute a remote command and pass in local file as input?

Is it possible to do this: ssh user@socket command /path/to/file/on/local/machine That is to say, I want to execute a remote command using a local file in one step, without first using scp to copy ...
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1answer
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Is there an easy way to update information in known_hosts when you know that a hosts key has changed?

If a host's operating system has been re-installed and had its public key regenerated sshing to it will of course fail because the new key doesn't match the old one. Is there an easier way to tell ...
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6answers
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Copy input to clipboard over SSH?

Here's my usage case: I'm often connected to other computers over SSH for work and I often need to copy and paste documents/text from the server to locally running editors for writing examples and ...
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3answers
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Can SSH passwords be sniffed out over Wi-Fi?

When you ssh, can the password you enter to connect, be intercepted if you're using untrusted public Wi-Fi (coffee shop, library, airport, etc).
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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
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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 ...
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3answers
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How to SSH into a specific directory?

I frequently login to a server, then cd into a specific directory. Is it possible to simplify these two commands into one? ssh bob@foo cd /home/guest I'd like to avoid changing anything on 'foo' ...
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4answers
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How to avoid being asked passphrase each time I push to Bitbucket

I set up my ssh stuff with the help of this guide, and it used to work well (I could run hg push without being asked for a passphrase). What could have happened between then and now, considering that ...
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SCP from one server to another without password prompt

What is the best way of doing SCP from one box to the other without prompting for password? There are two servers: Server A (10.152.2.10): /home/oracle/export/files.txt Server B (10.152.2.11): ...
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3answers
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How to close (kill) ssh ControlMaster connections manually

With the following .ssh/config configuration: ControlMaster auto ControlPath /tmp/ssh_mux_%h_%p_%r ControlPersist 4h How to close the persisting connection before the 4 hours? I know you can make ...
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2answers
801 views

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
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Given keys in ~/.ssh/authorized_keys format, can you determine key strength easily?

~/.ssh/authorized_keys[2] contains the list of public keys. Unfortunately, each public key does not specify the key strength ( number of bits ). Is there a utility that can process this file line by ...
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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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3answers
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SSH: tunnel without shell on ssh server

I have to set up a tunnel between two hosts. For this i use ssh in this way: ssh -L MY_LOCAL_PORT:FOREIGN_ADDRESS:FOREIGN_PORT MYUSER@SSH_SERVER after that, I login into my SSH_SERVER. How can I ...
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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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1answer
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Limits of SSH multiplexing

I have the following entry in my .ssh/config file Host AAA User BBB HostName CCC ControlMaster auto ControlPath ~/.ssh/%r@%h:%p The above allows me to multiplex multiple ssh ...
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5answers
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How to copy a file that is still being written over ssh?

Here is the situation: I am uploading a large file from client A to a server using sftp. I also need to download this file from the server to client B over ssh. What I would like to do is start ...
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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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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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4answers
721 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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4answers
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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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2answers
961 views

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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2answers
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Starting firefox on a remote host (over ssh) opens a new window locally: what is happening?

I have never noticed this behaviour before, and am a little confused as to what is happening. I have a local copy of firefox running, then ssh (ssh -X <url>) into a remote server and start a ...
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4answers
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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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2answers
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ssh-add in not persistent between reboots

I add a ssh key to the agent by $ ssh-add ~/.ssh/id_rsa_mac Identity added: /Users/alex/.ssh/id_rsa_mac (/Users/alex/.ssh/id_rsa_mac) After reboot I don't have this key added anymore: $ ssh-add -l ...
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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 to ensure SSH port is only open to a specific IP address?

This is my /etc/sysconfig/iptables: It has two ports open 80 apache and 22 for ssh. # Firewall configuration written by system-config-firewall # Manual customization of this file is not recommended. ...
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3answers
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Differences between VNC and ssh -X

Why would you use VNC (or for that matter NX) instead of just using ssh -X (-Y). I read that VNC uses less bandwidth, but is there any other differences/advantages with respective tool?
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2answers
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Can I unfreeze bash or vim when SSH session freezes from timeout? [duplicate]

When my SSH session times out, the whole terminal freezes. Is there any way to break out of that connection? CTRL+C doesn't cut it.
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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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2answers
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Use ssh with a specific network interface

I'm using openconnect to connect to vpn. After entering my credentials, I get this: POST https://domain.name/... Got CONNECT response: HTTP/1.1 200 OK CSTP connected. DPD 30, Keepalive 30 Connected ...
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7answers
425 views

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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3answers
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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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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 ...
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1answer
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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 ...
10
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1answer
665 views

Redirect linux console on boot

Is it possible on boot to redirect the console output to a screen session? The server has no monitor attached, and I'd like to be able to see the primary console output. I've seen other posts about ...
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9answers
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Automatically run commands over SSH on many servers

There is a list of IP addresses in a .txt file, ex.: 1.1.1.1 2.2.2.2 3.3.3.3 Behind every IP address there is a server, and on every server there is an sshd running on port 22. Not every server is ...
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3answers
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ssh remote server on some port other than 22 without password

I am usually connecting to the remote server with ssh user@server.com -p 11000 and then giving the password each time for user. How should I avoid entering the password each time I connect ...
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3answers
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Permit root to login via ssh only with key-based authentication

I have some doubts about certain ssh server configurations on /etc/ssh/sshd_config. I want the next behavior: Public key authentication is the only way to authenticate as root (no password ...
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7answers
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How do I work with GUI tools over a remote server?

I have an Ubuntu server running on EC2 (which I didn't install myself, just picked up an AMI). So far I'm using putty to work with it, but I am wondering how to work on it with GUI tools (I'm not ...
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2answers
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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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2answers
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How to ssh to a server using another server? [duplicate]

Possible Duplicate: ssh via multiple hosts For connecting to server B I have to first ssh to server A. What's the command line to access server B?
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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 ...
9
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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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2answers
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Is an SSH connection faster if I lower the RSA key size?

I have a very slow connection, and I need to use SSH on it. How can I increase "the speed"? I mean is using big RSA keypairs a large overhead? Would lowering the key size increase the effective ...
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2answers
830 views

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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1answer
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Why does SSH not consult /etc/hosts?

I'm administrating a networked environment where the users authenticate over NIS. All machines can be used to SSH into the server but one. On the machine in question, I get the message ssh: connect ...
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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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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 ...