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

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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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How to pull a file from a server using scp?

I am on machine A and want to pull a file from machine B. A$ scp <myuserid>@hostB:<path of file in B> . it says that: scp: <path of file in B>: No such file or directory But on ...
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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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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 ...
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1answer
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How to detect when a shell is owned by a remote SSH session?

My question is similar to this one, but I'm looking for something slightly different. I have a notebook PC that I use to access Linux machines on a network in two different scenarios: I have a ...
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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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Ssh login hook?

Is there a way to run a script/command every time a user connects using ssh? Can it be configured globally (i.e run the script when any user login)? I came across this question on Identica, but there ...
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4answers
586 views

Good practice to use same SSH keypair on multiple machines?

I recently got a new laptop for work, and I was wondering whether it'd be good practice to keep using the same RSA keypair as I'm using on my old work laptop. I'd really like to not have to create ...
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1answer
605 views

How can I limit ssh *remote* port forwarding?

I need to limit which ports can be remotely 'ssh -R' forwarded by an user. I know about permitopen option on authorized_keys, but as it says on man page it only limits local 'ssh -L' port forwarding ...
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Get ssh to forward signals

I want to be able to send signals (SIGINT is the most important) through ssh. This command: ssh server "sleep 1000;echo f" > foo will start sleep on server and after 1000 seconds it will put ...
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3answers
688 views

GVim compiled from source opened via SSH -X does not copy paste on selection

I'm using SSH (with -X specified) from a Ubuntu box to a RHEL4 box and running GVim. It opens as expected in my local X, but the copy and paste via select doesn't work. I cannot select text in GVim ...
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1answer
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Best Practices for SSH, tmux & GnuPG Agent

I'm attempting to consolidate my encryption software to GnuPG, and I'm running into a confusing problem. My primary unit is a headless server, and I exclusively work in tmux. There is no X session, ...
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4answers
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I am using `&`: why isn't the process running in the background?

I know that I can append & to a command to run the process in the background. I'm SSH'ing into an Ubuntu 12.04 box and running a python program with $python program.py & -- but when I go to ...
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3answers
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passwordless ssh for another username?

I want to do a passwordless ssh connection for a subversion project. Right now I'm using ssh+svn, and it's a little annoying, because I have to type the password any time I want to transact with the ...
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Run a diff between local and remote file

I'm connected on a host via ssh and I'd like to compare (let's say with diff) a certain config file against its counterpart on another host, also accessible via ssh, without having to manually ...
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How do I generate SSHFP records?

I need to setup SSHFP records in the DNS for my host. I have done some searching but I haven't found any good example. What are SSHFP records? What does SSHFP records look like? How do I create ...
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Creating a UNIX account which only executes one command

Is there a way to create a user account in Solaris which allows the users to run one command only? No login shell or anything else. I could possibly do it with /usr/bin/false in /etc/passwd and just ...
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SSH: which one is my public key

My university asked my SSH public key as I need access to universities computer cluster. I generated SSH key using linux ssh-keygen -t dsa command. However, I don't know what information they need ...
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1answer
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Use different username by default for a specific host

I have a different (assigned, non-changable) username on one of the servers I log to regularly, and I would like to avoid writing it down every time. Can I make these lines [tohecz@localhost ~]$ ssh ...
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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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How do I background an SSH session? [duplicate]

Possible Duplicate: How can I break away from an SSH session that has crashed? I have started an SSH session on the command line, but now I want to get back to my local command line. For ...
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1answer
623 views

Using SSH to connect to a new server without storing the host keys in the $HOME/.ssh/known_host file

I get the following output if I run the following command: -bash-3.2$ ssh -o "StrictHostKeyChecking no" 192.168.1.77 Warning: Permanently added '192.168.1.77' (RSA) to the list of known hosts. Last ...
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View Script Over SSH?

A friend, using a remote machine, SSHed to my machine and ran the following python script: while (1): ....print "hello world" (this script simply prints 'hello world' continuously). I am now ...
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851 views

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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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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Prevent SSH client passing TERM environment variable to server?

I'm currently using Fedora 18 gnome-terminal, then started tmux multiplexer in it. After I connected to a CentOS 5 server via ssh command, I find: ls result has no color tmux, screen, hexedit, htop ...
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Copying protected files between servers in one line?

I'd like to copy squid.conf from one server to another. The servers don't talk to each other. I'd like to go through my workstation. Both servers have the file, so it will be overwritten on the ...
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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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Not able to ssh in to remote machine using shell script in Crontab

Below is the script which i am trying to run, which runs without any issue for i in `seq 200 2100` do usr=(`ssh -t -t -o ConnectTimeout=60 machine$1 finger | tail -1 | awk '{print$1}'`) echo ...
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1answer
358 views

mkdir: cannot create directory: Function not implemented

I am in college and have to submit my cs homework from a school Linux machine, but I like doing the homework on my laptop (Mac). So instead of copying my files over every time, then submitting them, I ...
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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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1answer
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Does ssh-agent store my passphrase?

Is it possible to determine the passphrases of private keys added to ssh-agent? I'm thinking along the lines of someone with root privileges trying to find out my passphrase after I have added the ...
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How to restrict an SSH user to only allow SSH-tunneling?

How can I restrict a user on the ssh server to allow them only the priviledges for SSH TUNNELING? i.e. So they cannot run commands even if they log in via ssh. My Linux servers are Ubuntu 11.04 and ...
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Terminate dropped SSH sessions

My SSH sessions seem to be dropping though that is not my major problem - the major problem is my previous sessions are still alive, worse yet one of them is running visudo preventing me from ...
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1answer
2k views

Forward all ports SSH

I have a question about SSH/Port forwarding. I haven't found the solution anywhere and don't know if there is any. I have a server behind my NAT box at home. I have port forwarding from my NAT box to ...
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1answer
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SSH causes while loop to stop

I have finally managed to boil down a problem I have been struggling with for a few weeks. I use SSH with "authorized keys" to run commands remotely. All is fine except when I do it in a while loop. ...
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3answers
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Disable colours on terminal and SSH

My local Linux machine has coloured terminal output like this; When I SSH to a pfSense/BSD box it changes the colours like this; Even when I SSH from to a machine that doesn't have a coloured ...
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How to add a ssh user who only has permissions to access specific folder?

How to add an ssh user who only has permissions to access specific folder? useradd -d /var/www/xyz.com.tr/musteri -s /bin/bash -g sshd musteri I created a user called musteri. I set its home ...
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Bash autocomplete in ssh session

It seems that bash doesn't want to autocomplete commands (what's annoying me right now is not autocompleting apt-get) when I'm logged into my machine from SSH. Is there some setting that will allow ...
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How to efficiently use 3D via a remote connection?

I have one weak PC (client) but with acceptable 3D performance, and one strong PC (server) which should be capable of running an application using OpenGL twice, i.e. once locally and once remotely for ...
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1answer
771 views

stderr over ssh -t

This sends output to STDERR, but does not propagate Ctrl+C (i.e. Ctrl+C will kill ssh but not the remote sleep): $ ssh localhost 'sleep 100;echo foo ">&2"' This propagates Ctrl+C (i.e. ...
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Weird SSH issue, ssh works with -t but freezes without it

When I ssh into one of my servers, it seems to log in, but then hangs before giving me the prompt (message debug2: shell request accepted on channel 0 is the last log entry). Though the odd thing is ...
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Failing to block brute force ssh with iptables

I'm trying to block (slow down) brute force attacks on my sshd server. I'm following this guide http://www.rackaid.com/resources/how-to-block-ssh-brute-force-attacks/ which basically says I need to ...
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3answers
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ssh, start a specific shell, and run a command on the remote machine?

I am in a situation where several users are sharing the same user account on a remote machine. I have a "personal" directory where I wrote my own .zshrc file, and I would like to have a way to: ...
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exit out of all SSH connections in one command and close PuTTY

Is there a way to back out of all SSH connections and close PuTTY in "one shot"? I work in Windows 7 and use PuTTY to SSH to various Linux hosts. An example of the way I find myself working: SSH to ...
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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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4answers
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How to make putty to not break my session after some time?

Each time putty is breaking session after some time if I am doing nothing. There is no any time parameter on putty so how can I stay my putty ssh session always Alive ?
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Is there a way to check a users SSH key to see if the passphrase is blank

I'm looking to lock down our Solaris 10, RHEL 5, and SLES 11.2 servers. It has come to my attention that some of the users have no passphrase for their SSH keys. Is there a way I can check for this ...
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ssh Connection refused: how to troubleshoot?

I'm trying: $ ssh eric@myserver where myserver is a machine in the intranet. I can ping myserver or respond to HTTP on port 8080, etc, but when I try ssh, I get ssh: connect to host myserver port ...