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

learn more… | top users | synonyms

20
votes
6answers
30k views

How can I run a script immediately after connecting via SSH?

I started to ask this question but answered it while I had it open. I'm going to post this question, follow it up with my solution and leave it open to other potential solutions. <backstory> I'...
20
votes
7answers
5k views

OS X: how to keep the computer from sleeping during a ssh session

When I ssh into a OS X computer on my network the session lasts until the OS X goes into sleep mode. Is there a way to prevent this from happening during my SSH session, apart from physically bumping ...
20
votes
3answers
2k views

How to prevent shutdown when an SSH user is logged in?

I'm administrating a networked environment and I had an interesting situation arise yesterday. When a host is required to shutdown by a regular user, it refuses to do so if other users are logged in ...
19
votes
3answers
2k views

ssh via multiple hosts

To get to my machine in my office, at the moment I am doing this: me@home:~$ ssh unix.university.com me@unix:~$ ssh unix.department.univeristy.com me@unix.department:~$ ssh office-machine.department....
19
votes
3answers
21k views

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 ...
19
votes
5answers
13k views

Does a `scp` transfer close when I close the shell?

I have scp transfer (from one remote server to another), that is quite big. So maybe I want close the computer from which I executed this command, will this end the transfer? I have ssh access to ...
19
votes
4answers
12k views

Can I pipe /dev/video over ssh

I have two computers, a desktop in my office ( with a webcam attached ) and a laptop somewhere else on the network. Usually I take a look at my office through my webcam by running ssh Office -Y "...
18
votes
2answers
14k views

What's ssh port forwarding and what's the difference between ssh local and remote port forwarding [duplicate]

I feel confused about ssh port forwarding and the difference between ssh local and remote port forwarding. Could you please explain them in detail and with examples? Thanks!
18
votes
3answers
12k views

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' ...
18
votes
3answers
34k views

What difference between openssh key and putty key?

I've found that ssh-keygen ("ssh" package) produces different keys from puttygen ("putty" package). If I create public and private keys with ssh-keygen some ssh-servers will not accept my keys. If I ...
18
votes
7answers
49k views

How to download a file through an SSH server?

I have a server in USA (Linux box B), and my home PC (Linux box A), and I need download a file from website C, The issue is, it is very slow to download a file direct from A, so I need download the ...
18
votes
2answers
19k views

Unable to use -o allow_other with sshfs (option enabled in fuse.conf)

I have the following on my /etc/fuse.conf file: # Set the maximum number of FUSE mounts allowed to non-root users. # The default is 1000. ...
18
votes
1answer
9k views

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. ...
18
votes
7answers
15k views

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 ...
17
votes
10answers
70k views

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 ...
17
votes
3answers
15k views

Encrypting file only with SSH -priv-key?

Suppose I want to encrypt a file so that only I can read it, by knowing my SSH private key password. I am sharing a repo where I want to encrypt or obfuscate sensitive information. By that, I mean ...
17
votes
4answers
41k views

How to delete a file on remote machine via SSH by using a Shell Script?

I am writing a Shell Script where I have to delete a file on a remote machine via a Shell Script. Flow manually: ssh username@domain.com .. then at domain: cd ./some/where rm some_file.war How ...
17
votes
2answers
6k views

How to terminate remotely called “tail -f” when connection is closed?

I just noticed that if I execute ssh user@remote_host tail -f /some/file , then tail -f /some/file keeps running on the remote_host even if ssh connection is closed! So, after several connects and ...
17
votes
4answers
14k views

Autocomplete server names for SSH and SCP

I have a few servers configured in ~/.ssh/config, such as alpha and beta. How might I configure Bash such that the commands ssh al<tab> and scp file.tgz al<tab> autocomplete the names of ...
17
votes
1answer
1k views

Transfer a file over a unstable SSH connection

I'm trying to upload some big files (around 10GB) with a slow upload speed (200kb/s) on a often disconnected SSH connection (due to poor network conditions). I'm trying to use scp, but if there is a ...
17
votes
2answers
4k views

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.
17
votes
4answers
76k views

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?
17
votes
7answers
4k views

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 ...
17
votes
1answer
8k views

How can I configure a reverse SSH connection to the connecting computer?

I'm going to be deploying a number of machines in the near future which will be behind routers. It won't be feasible to set up dynamic DNS on each router and port forwarding, so is there a way I can ...
17
votes
5answers
5k views

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 'f\...
16
votes
6answers
3k views

Is it possible to use Unix commands to `cp` a file in my subdirectory into a remote computer via SSH?

I have a series of software files downloaded into my subdirectory "~/Downloads" on my personal computer. I am also using bash to connect remotely to a computer using ssh. Is it possible to transfer ...
16
votes
4answers
35k views

How do you copy the public key to a ssh-server?

Here is what I have tried, and I got an error: $ cat /home/tim/.ssh/id_rsa.pub | ssh tim@just.some.other.server 'cat >> .ssh/authorized_keys' Password: cat: >>: No such file or directory ...
16
votes
3answers
2k views

Why change default ssh port?

I've noticed lot of admins change default ssh port. Is there any rational reason to do so?
16
votes
8answers
9k views

How do I copy all files and directories except certain ones over ssh?

Using the Linux command line, I use the scp command to copy up all the files and folders from a certain directory. However, I don't like to consume wasted bandwidth for copying up things I rarely ...
16
votes
4answers
8k views

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 ...
16
votes
1answer
17k views

Convert OpenSSH private key into SSH2 private key

Is there a way to convert existing pair of OpenSSH keys to the SSH2 (ssh.com format) pair of keys? UPD: since there are some answers about ssh-keygen suddenly appeared, I'll explain where I came ...
16
votes
2answers
12k views

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 ...
16
votes
3answers
16k views

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?
16
votes
2answers
3k views

Will my MySQL query continue to run even if my ssh connection drops?

I've connected to a server over SSH and logged in to mysql, and asked it to run a query (the results of which are dumped into a CSV) that could take well over an hour. Although I have instructed my ...
15
votes
2answers
3k views

Accidently created a file called -X, how can I delete it? [duplicate]

Possible Duplicate: How do I delete a file whose name begins with “-” (hyphen a.k.a. dash or minus)? Like an idiot, I ran this command: tar -cf -X awstats-icon icon tarfile....
15
votes
3answers
33k views

Which users are allowed to log in via SSH by default?

When I set up my Debian 6, I was wondering, which users apart from root whose password I know can log into my system via SSH? When I install Apache 2 a user called www-data gets created. Does this ...
15
votes
6answers
20k views

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 ...
15
votes
5answers
42k 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 ...
15
votes
3answers
46k views

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 ...
15
votes
4answers
6k views

How can I keep my SSH sessions from freezing?

I have ServerAliveInterval and in case of few machines also ClientAliveInterval set to 540 in SSH client/server configuration files (I suppose setting it to more than that would not be a good idea). I ...
15
votes
4answers
6k views

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 ...
15
votes
2answers
8k views

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 ...
15
votes
4answers
20k views

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 low-...
15
votes
2answers
28k views

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 ...
15
votes
4answers
11k views

How can I solve this ssh-agent problem?

I'm using Linux Mint, and have not been able to get gnome-keyring to unlock automatically at login, it seems. A symptom of my problem is as follows: $ ssh-add Identity added: /home/me/.ssh/id_rsa (/...
14
votes
3answers
78k views

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 ...
14
votes
4answers
11k views

Run a diff between local and remote files

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 an another host, also accessible via ssh, without having to manually ...
14
votes
5answers
54k views

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 ?
14
votes
3answers
2k views

How to tell if SSH'd into machine? [duplicate]

Is it possible to tell if a terminal is SSH'd into a machine ? some kind of command to do this for me and execute something if I am SSHd?
14
votes
3answers
21k views

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): /...