ssh-agent error "Could not open a connection to your authentication agent." [duplicate]

I am running into this error of:

$ git push heroku master
Warning: Permanently added the RSA host key for IP address '50.19.85.132' to the list of known hosts.
!  Your key with fingerprint b7:fd:15:25:02:8e:5f:06:4f:1c:af:f3:f0:c3:c2:65 is not authorized to access bitstarter.

I tried to add the keys and I get this error below:

$ ssh-add ~/.ssh/id_rsa.pub
Could not open a connection to your authentication agent.

Solution 1:

Did You Start ssh-agent?

You might need to start ssh-agent before you run the ssh-add command:

eval `ssh-agent -s`
ssh-add

Note that this will start the agent for msysgit Bash on Windows. If you're using a different shell or operating system, you might need to use a variant of the command, such as those listed in the other answers.

See the following answers:

  1. ssh-add complains: Could not open a connection to your authentication agent
  2. Git push requires username and password (contains detailed instructions on how to use ssh-agent)
  3. How to run (git/ssh) authentication agent?.
  4. Could not open a connection to your authentication agent

To automatically start ssh-agent and allow a single instance to work in multiple console windows, see Start ssh-agent on login.

Why do we need to use eval instead of just ssh-agent?

To find out why, see this comment.

Public vs Private Keys

Also, whenever I use ssh-add, I always add private keys to it. The file ~/.ssh/id_rsa.pub looks like a public key, I'm not sure if that will work. Do you have a ~/.ssh/id_rsa file? If you open it in a text editor, does it say it's a private key?

Solution 2:

I tried the other solutions to no avail. I made more research and found that the following command worked. I am using Windows 7 and Git Bash.

eval $(ssh-agent)

More information in: https://coderwall.com/p/rdi_wq (web archive version)

Solution 3:

The following command worked for me. I am using CentOS.

exec ssh-agent bash