遇到从github git clone不下来，报Permission denied (publickey). fatal: Could not read from remote repository.

错误

vigevige@ubuntu:~/make-cool-play&build-cool-play$ git git@github.com:nginx/nginx.git
git: 'git@github.com:nginx/nginx.git' is not a git command. See 'git --help'.
vigevige@ubuntu:~/make-cool-play&build-cool-play$ git clone git@github.com:nginx/nginx.git
Cloning into 'nginx'...
Permission denied (publickey).
fatal: Could not read from remote repository.


Please make sure you have the correct access rights
and the repository exists.
vigevige@ubuntu:~/make-cool-play&build-cool-play$ git clone git@github.com:arut/nginx-rtmp-module.git
Cloning into 'nginx-rtmp-module'...
Permission denied (publickey).
fatal: Could not read from remote repository.


Please make sure you have the correct access rights
and the repository exists.

解决办法

https://help.github.com/articles/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent/

https://help.github.com/articles/adding-a-new-ssh-key-to-your-github-account/