Highest scored 'ssh-keys' questions

230 votes

11 answers

712k views

"Add correct host key in known_hosts" / multiple ssh host keys per hostname?

Trying to ssh into a computer I control, I'm getting the familiar message: @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@...

Samuel Edwin Ward

2,483

asked Oct 13, 2011 at 14:01

177 votes

5 answers

99k views

What's the difference between authorized_keys and authorized_keys2?

Just wanted a quick summary of the differences between them and why there are two?

Jon

2,131

asked Feb 24, 2010 at 10:57

137 votes

4 answers

57k views

What significance does the user/host at the end of an SSH public key file hold?

I can’t figure out why does an SSH public key file generated by ssh-keygen have a user and host at the end of it. Example: id_rsa.pub ssh-rsa ... rest of file ... /CA9gyE8HRhNMG6ZDwyhPBbDfX root@...

Basil A

2,140

asked Dec 16, 2015 at 21:04

135 votes

4 answers

337k views

how do you create an ssh key for another user?

I'm trying to create an ssh key for another user. I'm logged in as root. Can I just edit the files generated by ssh-keygen and change root to the user I want?

user962449

1,477

asked Oct 22, 2011 at 19:24

111 votes

8 answers

30k views

Why does my OpenSSH key fingerprint not match the AWS EC2 console keypair fingerprint?

When I import my OpenSSH public key into AWS EC2's keyring the fingerprint that AWS shows doesn't match what I see from: ssh-keygen -l -f my_key It is a different length and has different bytes. ...

Craig Ringer

11.2k

asked Jun 10, 2014 at 4:28

98 votes

1 answer

189k views

How do I validate an RSA SSH public key file (id_rsa.pub)?

Is there a command I can use to verify the public key (id_rsa.pub), just the format only. Sometimes I have added a new linebreak, sometimes the file missed the ssh-rsa prefix, so is there a command ...

Ryan

6,031

asked Nov 29, 2012 at 5:13

87 votes

1 answer

75k views

SSH Allow Password For One User, Rest Only Allow Public Keys [duplicate]

Is it possible with ssh to allow passwords from a certain user, but deny using passwords for everybody else? Basically I want to allow password auth for user justin but everybody else must use public ...

Justin

5,438

asked Sep 1, 2011 at 22:33

84 votes

16 answers

695k views

What causes SSH error: kex_exchange_identification: Connection closed by remote host?

I setup a SSH server online that is publicly accessible by anyone. Therefore, I get a lot of connections from IPs all over the world. Weirdly, none actually try to authenticate to open a session. I ...

soliz

942

asked May 4, 2020 at 9:25

74 votes

11 answers

34k views

Why is SSH password authentication a security risk?

Most guides for OpenSSH configuration advise to disable password authentication in favor of key-based authentication. But in my opinion password authentication has a significant advantage: an ability ...

Septagram

937

asked Nov 24, 2011 at 12:12

72 votes

8 answers

159k views

How to change a SSH host key?

I cloned a server and so they've the same RSA key fingerprint. It seems to be defined in /etc/ssh/ssh_host_rsa_key.pub. What is the correct way to change that? Thanks.

Pascal Polleunus

1,523

asked Jan 22, 2013 at 10:24

69 votes

3 answers

119k views

Temporarily disable ssh public key authentication from client

Is there a way to temporarily disable public key authentication when ssh'ing, and use password authentication instead? I currently want to access remote server, but I'm using another laptop, not mine....

Nsukami _

801

asked Mar 28, 2013 at 14:15

56 votes

11 answers

290k views

Is there an equivalent to ssh-copy-id for Windows?

Is there any equivalent or port of ssh-copy-id available for Windows? That is, is there an easy way to transfer SSH keys from a local machine to a remote server under Windows? In case it helps, I'm ...

Matt V.

837

asked Jan 20, 2011 at 18:34

54 votes

7 answers

23k views

How to get all fingerprints for .ssh/authorized_keys(2) file

Is there a simple way to get a list of all fingerprints entered in the .ssh/authorized_keys || .ssh/authorized_keys2 file? ssh-keygen -l -f .ssh/authorized_keys will only return fingerprint of ...

childno͡.de

682

asked Aug 1, 2012 at 10:29

47 votes

9 answers

119k views

Auto accept rsa key fingerprint from command line

I've tried yes | ssh [email protected] to try to accept the RSA key fingerprint, but am still prompted if I'm sure I want to connect. Is there a way to make this automatic?

VenomFangs

727

asked Oct 21, 2014 at 15:07

44 votes

1 answer

44k views

What is the meaning of an equal sign = or == at the end of a SSH public key?

I just noticed that most of the ssh pubkeys in my authorized_keys end on == or = E.g. ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEA9ZUwxXn2HZAAUswoaV8t2sQPvolVWDI053f0giNN154Zyi9FtWJKvyLHXoxW4IzFxgx+m6EYqXG/...

Lukas Loesche

960

asked Feb 9, 2012 at 13:28

41 votes

8 answers

88k views

Automating ssh-copy-id

I have some arbitrary number of servers with the same user/pass combination. I want to write a script (that I call once) so that ssh-copy-id user@myserver is called for each server. Since they ...

devin

1,266

asked Aug 30, 2011 at 18:17

41 votes

5 answers

8k views

Smoothest workflow to handle SSH host verification errors?

This is a simple issue that we all face and probably resolve manually without giving much thought. As servers change, are re-provisioned, or IP addresses reallocated, we receive the SSH host ...

ewwhite

198k

asked Aug 12, 2012 at 20:54

38 votes

2 answers

4k views

Is there a security risk to disclosing your SSH known_hosts file?

I'm speaking at a conference next week about some software tools I've created. My laptop will be shown on a projector screen during this presentation. The presentation will be videotaped and posted ...

Matt Korostoff

495

asked Jul 11, 2015 at 18:32

38 votes

7 answers

98k views

Unable to ssh to GCE: "Permission denied (publickey)"

I created a VM via Bitnami in Google Compute Engine. Previously, I was able to ssh via the Bitnami web interface. I tried to ssh via terminal on my Mac but kept getting the Permission denied (...

NEO

781

asked Nov 2, 2014 at 15:52

37 votes

2 answers

37k views

ssh-copy-id specifying which key and without password

I have a public key in a server(host) that I want to transfer to another server(target). The host server has a bunch of keys in .ssh/ folder, i want to copy just one of them to the target server (it'...

Lucas Mattos

483

asked Jul 12, 2016 at 15:31

37 votes

3 answers

105k views

ssh-copy-id - permission denied (publickey) [closed]

I want to set up ssh tunnel to the mysql server which is in computer which has virtual machine. Also the tunnel has to work if the machine is restarted. So lets say A is computer with linux software. ...

Darius.V

539

asked Apr 21, 2015 at 13:21

36 votes

3 answers

39k views

How to configure ssh client to use private keys automatically

I'm always running ssh with the -i parameter and it's a hassle to always type in the correct key for whatever host I'm connecting to. Is there a config file or something (on Mac) to define which ...

Leopd

1,907

asked Apr 22, 2011 at 19:14

34 votes

1 answer

29k views

Only allow password authentication to SSH server from internal network

I have an OpenSSH 5.9p1 server running on Ubuntu Precise 12.04 which accepts connections from both the internal network and the Internet. I'd like to require public key authentication for connections ...

mgorven

31k

asked Jul 11, 2012 at 16:37

33 votes

3 answers

30k views

openssh - Adding an ssh key from putty to authorized_keys

I have been provided with an ssh key by a colleague to add to the authorized_keys file for an account on a linux server so they can access that account. The file looks something like this: ---- ...

Michael Slade

471

asked Aug 16, 2016 at 7:21

28 votes

6 answers

12k views

Have a system that expires SSH keys every 90th day [closed]

I have a customer that now requires us to change every password every 90th day due to their interpretation of GDPR. That's fine for the web-based system we develop for them because we can just ...

mr D

280

asked Sep 18, 2018 at 7:45

28 votes

2 answers

142k views

how to connect to mongodb server via ssh tunnel

It was easy for me to connect to my remote mysql server on AWS using a sequelpro, however I'm struggling with doing the same thing with mongodb. I tried setting up an ssh tunnel via command line ...

abbood

1,127

asked May 22, 2014 at 10:51

27 votes

11 answers

79k views

SSH aborts with Too many authentication failures

I'm attempting to run this simple provisioning script but I'm encountering errors when running vagrant up and then vagrant provision commands. I read that I needed to create a /etc/ansible/hosts file ...

Ashley

528

asked Mar 8, 2014 at 22:35

26 votes

8 answers

32k views

A system for distributing SSH public keys

We have many different systems that are managed by several people. We have chosen to use SSH public key authentication to access those systems. This works great, as there is no need to manage or share ...

Jacek Konieczny

3,825

asked Feb 26, 2010 at 8:20

25 votes

5 answers

28k views

how to SSH to EC2 without explicitly using the pem key?

I have a windows as my main OS. Using VMware player, I setup a Ubuntu server 12.4 as a guest machine. The Ubuntu server have "ubuntu" user. I created a new EC2 instance + setup pem key. From the ...

user798562

251

asked Mar 15, 2013 at 14:25

25 votes

6 answers

24k views

Windows Password won't decrypt on AWS EC2 even with the correct private key

I created a new Windows instance on AWS EC2, using a keypair I created by uploading my public key from my local machine. The instance launched fine, but it won't decrypt the password. It reports: I'...

Craig Ringer

11.2k

asked Jun 10, 2014 at 4:44

24 votes

3 answers

36k views

Putting RSA keys into azure key vault

How can I store my key pair (typically the id_rsa and id_rsa.pub) in azure key vault. I want to put the public key in my GIT service and allow a virtual machine to download the private key from Azure ...

MercilessMaverick

407

asked May 4, 2017 at 6:46

24 votes

2 answers

72k views

Load key "privkey.ppk" invalid format

What have I done: I'm trying to connect to my remote server with private key with ssh -i privkey.ppk root@ip But it's returning an error. Error message: Load key "privkey.ppk": invalid format root@...

AATHITH RAJENDRAN

519

asked Feb 27, 2020 at 6:58

23 votes

5 answers

93k views

SSH Public Key Format

I have a public key in the format: ---- BEGIN SSH2 PUBLIC KEY ---- Comment: "somename-20060227" AAAAB3NzaC1yc2EAAAABJQAAAIBmhLUTJiP[and so on]== ---- END SSH2 PUBLIC KEY ---- Usually I see keys in ...

Björn

447

asked Apr 18, 2012 at 14:38

22 votes

7 answers

63k views

How to generate host SSH keys via ansible?

I'm trying to re-generate ssh host keys on a handful of remote servers via ansible (and ssh-keygen), but the files don't seem to be showing up. The playbook runs OK, but the files on the remote are ...

Server Fault

3,784

asked Apr 30, 2018 at 19:09

22 votes

9 answers

80k views

Trying to SSH in to remote computer but still asking for password

Trying to SSH in to remote computer but still asking for password. I have a number of computers running SElinux and only one of them is giving me a hard time using ssh without the password. I did ...

JMS1969SF

221

asked Jan 9, 2013 at 14:24

22 votes

4 answers

26k views

How do I import a RSA SSH key into GPG as the _primary_ private key?

I currently have a SSH key that I've used for a while and I'd like to start using GnuPG with a new keyring. However, given that I've used my key for ages, I would like to still use that key in GPG as ...

SineSwiper

2,638

asked Jan 5, 2012 at 15:16

22 votes

1 answer

14k views

ssh command line specify server host key fingerprint

Using ssh command line (OpenSSH), can I specify the server's host key fingerprint? This is possible with winscp.com using (e.g.) -hostkey="ssh-rsa 2048 AA:BB:CC...etc I have read the man page a ...

payo

323

asked Mar 25, 2015 at 0:37

20 votes

4 answers

2k views

Publishing id_rsa.pub for easier setup of new environments?

To make setting up passwordless SSH easier on new machines and environments, is there any reason why the id_rsa.pub file (just the public half of the key pair) could not be published somewhere on the ...

DouglasDD

552

asked Mar 26, 2014 at 0:31

20 votes

2 answers

3k views

Receiving a private key from server admin: ok or not?

I am to get access to a remote SFTP server. The admin has created a user for me, and generated a public/private key pair for me. Then he securely sent me the private key file, which I use for ...

matthiash

311

asked Jun 29, 2016 at 18:50

19 votes

4 answers

42k views

Turn off strict checking of ssh keys

Each user creates and destroys 15+ VM's per day. The VM's are created in the company's internal OpenStack cloud. Every time a new vm is assigned an ip address which has previously been handed out, ...

spuder

1,745

asked May 10, 2013 at 23:04

19 votes

4 answers

101k views

How to set public SSH key for root user on server?

I'm trying to follow Slicehost Document to setup my server. I reached SSH section. I made it as written, but when i logged out from root, i cant access root@IP_ADDRESS -p 30000 again! but i can access ...

amrnt

359

asked May 10, 2010 at 18:01

18 votes

4 answers

2k views

SSH into NAT'd servers on the same public IP address

I am trying to SSH from in office X to a few Linux boxes in office Y. The Linux boxes in office Y are behind NAT and each run on their own ports. I can successfully reach all of them through SSH, but ...

Copy Run Start

734

asked Aug 29, 2015 at 0:26

17 votes

2 answers

6k views

Are there any security benefits to deploying custom SSH DH groups to client-only systems?

One suggested mitigative strategy against Logjam-related attacks on SSH is to generate custom SSH Diffie-Hellman groups using something like (the below being for OpenSSH) ssh-keygen -G moduli-2048....

user

4,455

asked May 23, 2015 at 12:28

16 votes

1 answer

18k views

SSH ForwardAgent multiple hops

I've been looking for a solution to the following problem for the past 2 hours with no luck. Development: I'm using publickey authentication to connect to my servers. I use ssh-agent forwarding in ...

liquidity

418

asked Dec 16, 2013 at 4:11

16 votes

2 answers

13k views

How to revoke an ssh certificate (not ssh identity file!)

I've generated an ssh certificate like this: ssh-keygen -f ca_key # generate a ssh keypair for use as a certificate generate a host key ssh-keygen -s ca_key -I cert_identifier -h host_key.pub specify ...

rorycl

858

asked Apr 28, 2011 at 22:25

14 votes

1 answer

2k views

Can Bash Tell Me Which SSH Public Key Was Used To Authenticate?

Let's say I want to track my root users. Each of them has a unique private key and their public keys have been stored in /root/.ssh/authorized_keys. Given that each user logs in with their unique key ...

PP.

3,426

asked Sep 20, 2013 at 10:06

14 votes

1 answer

27k views

AuthorizedKeysFile line commented out but still seems to work

I'm setting up a server on Linode and following their Securing Your Server guide. They recommend setting up ssh key pair authentication. I have already uploaded my public key to server and the key ...

Adam Johns

315

asked May 11, 2015 at 1:28

14 votes

5 answers

6k views

Choose identity from ssh-agent by file name

Problem: I have some 20-30 ssh-agent identities. Most servers refuse authentication with Too many failed authentications, as SSH usually won't let me try 20 different keys to log in. At the moment, I ...

leoluk

541

asked Jun 24, 2012 at 10:06

13 votes

1 answer

34k views

one ssh key file for multiple machines, instead of pair to single machine?

I am currently implementing key pair login to my server as following: generate key pair from my local laptop: me@macbook:~ $ ssh-keygen -t rsa transfer pub key from laptop to server: me@macbook:$ ...

gilzero

449

asked May 14, 2012 at 7:23

13 votes

1 answer

8k views

User@host in a SSH-RSA public key

What role does the user@host that often appears at the end of a public ssh-rsa key play? Is it necessary? Does if serve any purpose in the authentication, or is it simply a record of who and where ...

usedTobeaMember

606

asked Mar 18, 2014 at 13:23

Questions tagged [ssh-keys]

Related Tags