Questions tagged [ssh]
Secure Shell; a network protocol that allows data transfer over a secure channel between two networked devices.
10,693
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How to tell git which private key to use?
ssh has the -i option to tell which private key file to use when authenticating:
-i identity_fileSelects a file from which
the identity (private key) for RSA or DSA authentication is read.
The ...
- 12.9k
758
votes
15
answers
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macOS keeps asking my ssh passphrase since I updated to Sierra
It used to remember the passphrase, but now it's asking it to me each time.
I've read that I need to regenerate the public key with this command, which I did:
ssh-keygen -y -f id_rsa > id_rsa.pub
...
- 7,701
520
votes
15
answers
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How to fix warning about ECDSA host key
I'm trying to setup password-less SSH on an Ubuntu server with ssh-copy-id myuser@myserver, but I'm getting the error:
Warning: the ECDSA host key for 'myserver' differs from the key for the IP ...
- 9,242
476
votes
18
answers
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An SSH tunnel via multiple hops
Tunneling data over SSH is pretty straight-forward:
ssh -D9999 [email protected]
sets up port 9999 on your localhost as a tunnel to example.com, but I have a more specific need:
I am working ...
- 7,388
471
votes
4
answers
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What is randomart produced by ssh-keygen?
When you generate a key, you get "randomart" from newer versions of OpenSSH. I am unable to find an explanation of why, and what I'm supposed to use it for.
Generating public/private rsa key pair.
...
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469
votes
18
answers
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Windows SSH: Permissions for 'private-key' are too open
I've OpenSSH 7.6 installed in Windows 7 for testing purposes. SSH client & server work just fine till I tried to access one of my AWS EC2 box from this windows.
It seems like I need to change the ...
- 5,463
446
votes
7
answers
1.3m
views
How do I exit an SSH connection?
I’m connecting to a server via SSH to send a message to a socket server using a command like:
ssh 181.169.1.2 -p 5566
After the connection is established and I write the message and send it I can’...
- 4,571
352
votes
19
answers
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views
How to reliably keep an SSH tunnel open?
I use an SSH tunnel from work to go around various idotic firewalls (it's ok with my boss :)). The problem is, after a while the ssh connection usually hangs, and the tunnel is broken.
If I could at ...
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307
votes
8
answers
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What is a SSH key fingerprint and how is it generated?
I always find that I get this message when I ssh into a new machine:
12:f8:7e:78:61:b4:bf:e2:de:24:15:96:4e:d4:72:53
What does it stand for? Will every machine have the same fingerprint every time?
...
- 5,337
305
votes
15
answers
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Too many authentication failures for *username*
I have a hostgator account with ssh access enabled. When trying to upload the generated .pub key file with this command:
rsync -av -e "ssh -p2222" /home/user/.ssh/key.pub [email protected]:.ssh/...
- 3,685
300
votes
11
answers
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views
Remove key from known_hosts
I built several virtual machines during the last few weeks. The problem is, the .ssh/known_hosts gives me the Man in the middle warning. This happens because another fingerprint is associated with the ...
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votes
12
answers
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Is there a way for one SSH config file to include another one?
In case it matters:
OS: Ubuntu 10.04
SSH: OpenSSH_5.3p1 Debian-3ubuntu5
I'd like one SSH config file to include another one. The use case would be to define whatever I want in my default .ssh/...
- 5,663
254
votes
8
answers
190k
views
Way to avoid ssh connection timeout & freezing of GNOME Terminal
When I connect via ssh to certain servers, it timeouts and "freezes" the terminal (doesn't accept input, doesn't disconnect, can't Ctrl-C to kill the ssh process or anything).
This is in Ubuntu's ...
- 2,878
253
votes
4
answers
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How to convert .ppk key to OpenSSH key under Linux?
I know that is possible to convert .ppk under puttygen in Windows, but how to do that on Linux? Is this possible ?
- 3,591
252
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8
answers
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How to make an SSH tunnel publicly accessible?
Referring back to this question, I am executing the below via OpenSSH (Client: Mac OS X 10.6 | Server: Linux Mint), however the port that is being tunneled is not working publicly:
ssh -R 8080:...
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votes
10
answers
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How can I avoid SSH's host verification for known hosts?
I get the following prompt everytime I try to connect a server using SSH. I type "yes", but is there a way to aovid this?
The authenticity of host '111.222.333.444 (111.222.333.444)' can't be ...
- 2,793
213
votes
7
answers
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views
scp between two remote hosts from my (third) pc
I have two remote hosts.
host1-> 10.3.0.1
host2-> 10.3.0.2
Both run an ssh server.
The ssh server listens on port 22 in host1 and on port 6969 in host2.
Now, using my local machine, I need to copy ...
- 2,231
212
votes
4
answers
203k
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210
votes
9
answers
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How do I configure SSH so it doesn't try all the identity files automatically?
I have been putting my ssh identity files inside my ~/.ssh/ folder. I have probably about 30 files in there.
When I connect to servers, I will specify the identity file to use with something like
...
- 18.2k
200
votes
13
answers
1.2m
views
How do I edit text files in the Windows command prompt?
On Unix I'd just use vi, but I don't know what the command is on Windows. I am actually trying to edit files over SSH with Windows Server 2008.
- 7,547
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votes
5
answers
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What's the difference between SCP and SFTP?
Usually, I use the scp command to transfer files on *nixes.
What's the difference between SFTP and SCP? Don't they both work on SSH?
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197
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10
answers
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How do I set up SSH so I don't have to type my password?
How do I set up SSH so I don't have to type my password when connecting to a host?
191
votes
16
answers
1.9m
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How do I fix a "cannot open display" error when opening an X program after ssh'ing with X11 forwarding enabled?
After launching the X11 app (XQuartz 2.3.6, xorg-server 1.4.2-apple56) on my Mac (OS X 10.6.8), opening an terminal in X11 and running xhost +, I then ssh -Y to my Ubuntu 10.04 VM (running on VMware ...
- 8,825
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votes
3
answers
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views
Howto force ssh to use a specific private key?
With ssh -i <private key filename> you can instruct ssh to use an extra private key to try authentication.
The documentation is not clear on how to explicitly use only that key.
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votes
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answers
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How can I tell how many bits my ssh key is?
I already created an ssh key for myself sometime in the past. I don't remember "how many bits" it is. How can I tell?
I'm wondering because I'm using hosting at nearlyfreespeech.net and their faq ...
- 1,915
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votes
8
answers
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views
Don't add hostkey to known_hosts for SSH
I want to connect to a host via SSH but I don't want the hostname to be added to my ~/.ssh/known_hosts.
How can I do that?
- 6,681
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votes
10
answers
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How to use Mac OS X Keychain with SSH keys?
I understand that since Mac OS X Leopard the Keychain has supported storing SSH keys. Could someone please explain how this feature is supposed to work.
I have some RSA keys that I've generated ...
- 1,778
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votes
9
answers
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how to avoid being asked "Enter passphrase for key " when I'm doing ssh operation on a remote host?
I'm ssh into a remote host (linux, fedora) and I want to do ssh operation(git with bitbucket) there. There is ssh-agent running on that machine,
$ ps -e|grep sh-agent
2203 ? 00:00:00 ssh-...
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votes
7
answers
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views
How can I tunnel all of my network traffic through SSH?
Whenever I'm using the internet from an insecure location (such as public wifi) I like to use an ssh tunnel (ssh -D port host) to ensure my traffic can't be sniffed. Unfortunately, there seem to be ...
- 1
151
votes
9
answers
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views
How do I make Bash my default shell on Ubuntu?
I have a .bash_profile in my home directory, but it isn't getting run on login. If I do the following, then things seem to be as I expect:
ssh myhost
bash
source ~/.bash_profile
But normally that ...
- 2,282
151
votes
11
answers
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views
When ssh'ing, how can I set an environment variable on the server that changes from session to session?
When I ssh into a server, how can I pass an environment variable from the client to the server? This environment variable changes between different invocations of ssh so I don't want to overwrite $...
- 4,607
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votes
6
answers
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How to prevent SSH from disconnecting if it's been idle for a while
I have a ssh connection to a machine which gets disconnected by that machine after 30 minutes of no user input. However, if I start something like top, the connection stays alive.
Since this is a ...
- 1,904
147
votes
6
answers
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SHA256 ssh fingerprint given by the client but only md5 fingerprint known for server
When connecting to a new/unknown server (with recent OpenSSH), for example:
ssh example.com
You get the fingerprint like below:
The authenticity of host 'example.org (192.0.2.42)' can't be ...
- 3,653
142
votes
24
answers
247k
views
Why is my SSH login slow?
I'm seeing delays in SSH Logins. Specifically, there are 2 spots where I see a range from instantaneous to multi-second delays.
Between issuing the ssh command and getting a login prompt and
between ...
- 1,882
137
votes
3
answers
186k
views
Where does Putty store known_hosts information on Windows?
How do I tell if Putty already knows about and has cached credentials for specific ssh servers?
Another way to ask this question is what is the Windows/Putty equivalent of a unix/ssh known_hosts file?...
- 3,091
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votes
7
answers
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SSH: The authenticity of host <host> can't be established
What does this message mean? Is this a potential problem? Is the channel not secure?
Or is this simply a default message that is always displayed when connecting to a new server?
I am used to ...
- 3,708
133
votes
8
answers
1.1m
views
How can I resolve the error "cannot execute binary file"?
When I login using SSH, all I can see is this...
-bash: /usr/bin/id: cannot execute binary file
-bash: [: : integer expression expected
I couldn't do anything in here. Commands such as halt, ...
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votes
15
answers
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How to force GPG to use console-mode pinentry to prompt for passwords?
Using gpg from a console-based environment such as ssh sessions fails because the GTK pinentry dialog cannot be shown in a SSH session.
I tried unset DISPLAY but it did not help. The GPG command line ...
- 7,853
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votes
8
answers
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Forward SSH traffic through a middle machine
SSH tunneling is very confusing to me. I am wondering if I can do this in Linux.
I have 3 machines..
A. My local machine at home.
B. Machine at work that I can SSH into (middle man).
C. My desktop ...
PKKid
127
votes
5
answers
230k
views
How can I SSH into "Bash on Ubuntu on Windows 10"?
I have Windows 10 Anniversary Edition with "Bash on Ubuntu on Windows" installed and working. I'd like to be able to SSH into this Ubuntu instance, but although I have openssh-server installed and ...
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118
votes
5
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views
Is it ok to share private key file between multiple computers/services?
So we all know how to use public key/private keys using SSH, etc. But what's the best way to use/reuse them? Should I keep them in a safe place forever? I mean, I needed a pair of keys for accessing ...
- 2,062
116
votes
3
answers
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views
How to upload local file to server through Linux terminal
I am trying to upload local files to server by using Putty or SSH but not getting upload there.
Is there any direct method to upload file from local to server from Linux terminal without using FTP ...
- 1,263
113
votes
3
answers
185k
views
How can I change the directory that ssh-keygen outputs to?
I want to run a command like:
ssh-keygen -t rsa -b 4096 -C "[email protected]"
My understanding is that ssh-keygen outputs to the home directory. I'm working on a networked computer using Git ...
- 1,233
112
votes
6
answers
305k
views
Downloading Folders to my Local via SSH
I am learning SSH as it seems there are no good SSH GUIs for Macs. I know how to make db dumps, cruise through the directories, etc, but the one last piece of the puzzle I need to learn is how to ...
- 1,245
109
votes
12
answers
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List open SSH tunnels
I use a lot of SSH tunnels to various servers on my linux machine (for tunnelling to databases, web servers etc) and it would be really handy to view a list of current open tunnels via a shell script. ...
- 1,193
107
votes
10
answers
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UDP traffic through SSH tunnel
The title pretty much sums it up. I would like to send UDP traffic through a SSH tunnel. Specifically, I need to be able to send UDP packets through the tunnel and have the server be able to send ...
- 64.1k
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votes
18
answers
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views
Linux "Top" command for Windows Powershell?
I am looking for a PowerShell cmdlet that can provide similar functionality to the Linux Top app. Something that refreshes at some given interval and displays the process list with CPU % util.
I have ...
TimAtVenturality
99
votes
4
answers
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views
Are GPG and SSH keys interchangable?
I want to generate an RSA key in GPG and use it in SSH login. Is this even possible? If so, how?
edit: see @wwerner's answer, I didn't try it but it seems to be the current solution (as of 2018)
- 1,147
98
votes
2
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How do I clear out the ssh-agent entries (on Mac OS X )?
I'm running Mac OS X, and it appears that after SSHing to several machines, using identity files, my 'ssh-agent' builds up a lot of identity / keys and then sometimes offers too many to a ...
- 18.2k
97
votes
6
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How do I remove an SSH forwarded port
I used ssh -L 10002:192.168.0.30:10002 192.168.1.135 to establish port forwarding but now I need to remove it.
How do I do this?
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