Mac Osx Generate Ssh Key

Posted on by
Mac Osx Generate Ssh Key Rating: 3,7/5 6480 votes

I‘ve reinstalled Linux on remote server and now trying to connect it over ssh using Mac OS X:

Macintosh Git SSH key setup. Ask Question Asked 3 years, 5 months ago. We are able to generate SSH keys, upload the public part, and then we can interact with GitHub. In the newer Mac OS, the user accounts don't have ssh-agent launched within each session and the user key is not remembered. As far as I can tell, when a user wants to. PuTTYgen is a key generator tool for creating pairs of public and private SSH keys. It is one of the components of the open-source networking client PuTTY. Although originally written for Microsoft Windows operating system, it is now officially available for.


But I’m getting an error which read as follows:

Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
Please contact your system administrator.
Add correct host key in /Users/user/.ssh/known_hosts to get rid of this message.
Offending key in /Users/user/.ssh/known_hosts:1
RSA host key for has changed and you have requested strict checking.
Host key verification failed.

How do I fix this problem under Mac OX X?

You need to run the following command to get rid of this problem. Open the terminal and type the following command:

Now you can connect to remote host with ssh:


This guide goes through setting up SSH keys on macOS Mojave 10.14 back to Mac OSX 10.11 and also a secure password-less SSH connection between a local macOS workstation and a remote server also running a Linux variant operating system.

The process requires generating a public and private key on the local computer and then adding the public key to the remote servers authorised list. What is great about this is that it allows a password prompt free session, handy for a lot of uses.

First thing that you need to do on your macOS machine is to create a directory that will store your SSH keys. Then you will generate a public and private key for your account, launch the Terminal and punch in some commands:

Create a .ssh Directory

Change to the home directory

Create a SSH directory name .ssh and move into it

Make sure that the file permissions are set to read/write/execute only for the user

Create your private and public key, the blank quotes at the end of the command gives the private key no password, so allowing for passwordless logins!

Change into the .ssh directory and list the contents of that .ssh directory

Mac Os X Generate Ssh Key

Thats your SSH keys created, the private key is the id_rsa and the public one is the, don’t give out the private one always keep that one only on your local machine.

Sharing the Public Key

Create an authorized_keys in the .ssh directory of the remote computer that you want to connect to.

Remove Ssh Key Mac

You can create automatic logins by adding the contents of your public key to the authorized_keys file on the remote device.

To see and copy your public key use the cat command and copy the contents:

On the remote computer if needed, change the permssions on the authorized_keys file to write to add the public key, on a new line paste in your public key, and change permissions back to read only after for security.

Allow write on authorised_keys

Generate Ssh Key Github

Paste the entire content with vi or nano into the authorized_keys file, if using nano use the -w flag to not use incorrect line breaks.

If the remote host does not have an “authorized_keys” file simply create one and after the public key is pasted in don’t forget to takeaway write permissions.

Going Both Ways

So now when you connect via SSH no password is prompted as the remote computer has your public key which is only decrypted by your private key held in your local .ssh/ directory. If you want the communications to be bilateral then repeat the process in the opposite order between the two.

Mac Osx Generate Ssh Key Mac

Now the two computers can securely connect with no password prompting, making it ideal to script between the two for file copies or back ups.

Doing it Quicker

Mac Os Generate Ssh Key

Now instead of typing in Linux generate pem from key.

Make an alias in your bash shell you could alias it to

Reload the the shell

Mac Osx Generate Ssh Key Online

Then all you have to type in is the alias