OpenSSH is one of the most popular implementations of SSH used today and available by default in many Linux and Unix-like operating systems.
Questions tagged [openssh]
1204 questions
500
votes
18 answers
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 permission on the private key file. This can be…
Sabrina
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333
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11 answers
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 virtual machine IP. In the .ssh/known_hosts…
Adam Matan
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268
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12 answers
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/config file and then pre-pend a couple of extra things in…
Joe Casadonte
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255
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8 answers
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:localhost:80 -N root@example.com The purpose is so the…
Trevor Rudolph
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219
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3 answers
How to 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.
Herman van Rink
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148
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6 answers
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 established. RSA key fingerprint is…
JonnyJD
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106
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5 answers
Bad owner or permissions on ssh config file
I have realized that I am no longer able to connect to the webserver at x.x.202.50 . Yesterday I have changed the following ssh configuration file: /share/homes/admin/.ssh/config by adding the following settings: # ssh (secure shell) configuration…
symp Ioio
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92
votes
5 answers
How can I find a list of MACs, Ciphers, and KexAlgorithms that my openssh client supports?
Is there a way to make ssh output what MACs, Ciphers, and KexAlgorithms that it supports? I'd like to find out dynamically instead of having to look at the source.
Colin Dean
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75
votes
5 answers
get SSH key fingerprint in (old) hex format on new version of openssh
It seems that openssh has changed the way it displays key fingerprints. I am trying to ssh from a client machine to a server: client: ubuntu 14.04 running OpenSSH 6.6.1 server: FreeBSD running OpenSSH 7.2p2. The client reports the md5 hash of the…
stochastic
- 1,003
70
votes
2 answers
ssh -o PreferredAuthentications: What's the difference between "password" and "keyboard-interactive"?
Both PreferredAuthentications=password and PreferredAuthentications=keyboard-interactive would prompt for the password, so what's the difference between them? I Google'd with the keywords ssh PreferredAuthentications password keyboard-interactive…
su.root
- 1,130
70
votes
4 answers
Can someone explain the 'PasswordAuthentication' in the /etc/ssh/sshd_config file?
On this page , the explanation for PasswordAuthentication given is: The option PasswordAuthentication specifies whether we should use password-based authentication. For strong security, this option must always be set to yes. But it fails to provide…
Zeta2
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66
votes
5 answers
SSH permission denied on correct password authentication
I could successfully SSH into my machine yesterday with the exact same credentials I am using today. The machine is running CentOS 6.3 . But now for some reason it is giving me permission denied. Here is my -v print out, sshd_config , and ssh_config…
Kentgrav
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63
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2 answers
How to name openssh public and private key pairs?
I am using public/private key pairs for a long time now. And nearly the same time I'm asking myself over and over again, which file extension I should use. It seems to be that at least for the public and the private(openssh) keys is no convention at…
Bernhard Laven
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61
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3 answers
How do you convert an SSH private key to a .ppk on the Windows command line?
I have generated a key pair with ssh-keygen . I now want to use the same key pair with PuTTY-based applications. Because I'm working in a CLI environment, I want to convert the key to the .ppk format from within this environment. Apparently, you can…
Oliver Salzburg
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5 answers
Disable "Permanently added ..." warning on local LAN
I have the following in my ssh_config to connect to machines on my local LAN and machines in a VM: Host 172.16.*.* StrictHostKeyChecking no UserKnownHostsFile /dev/null However, each time I connect it produces a warning: $ ssh jdoe@172.16.4.11…
jww
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