1.第一个问题
Permission denied (publickey).
fatal: Could not read from remote repository.
Please make sure you have the correct access rights and the repository exists.
2.第二个问题
ssh: Could not resolve hostname github.com: Name or service not known
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
使用git push命令推送时,总是会出现下面两个问题,一直以为是自己配置错误引起的,于是更改了RSA keys,可以使用了.可是退出终端后或者第二天再次使用时,又会出现同样的问题。前后自己什么也没有做，所以断定肯定不是自己这出问题了，而是github主机方面的。
查了一下，在这里果然有说道，试了一下，又好使了。
解释：Graphs where the mean response time goes up means there are issues (or possibly a DDOS) at github, and not at your end.
解决方法：使用ssh -T git@github.com命令测试一下就可以了，会去尝试主机，也就是相当于ping了一下。
yeqing@www:~/yeching.github.io$ ssh -T git@github.com
Hi yeching! You've successfully authenticated, but GitHub does not provide shell access.