Why can't ssh establish “the authenticity of host” for Github?
Both fingerprints of my host and my key on Github are the same. Why does the connection still fail?
ssh -vT email@example.com OpenSSH_5.9p1 Debian-5ubuntu1, OpenSSL 1.0.1 14 Mar 2012 debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 19: Applying options for * debug1: Connecting to github.com [188.8.131.52] port 22. debug1: Connection established. debug1: identity file /home/wangs/.ssh/id_rsa type 1 debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048 debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048 debug1: identity file /home/wangs/.ssh/id_rsa-cert type -1 debug1: identity file /home/wangs/.ssh/id_dsa type -1 debug1: identity file /home/wangs/.ssh/id_dsa-cert type -1 debug1: identity file /home/wangs/.ssh/id_ecdsa type -1 debug1: identity file /home/wangs/.ssh/id_ecdsa-cert type -1 debug1: Remote protocol version 2.0, remote software version OpenSSH_5.5p1 Debian- 6+squeeze1+github12 debug1: match: OpenSSH_5.5p1 Debian-6+squeeze1+github12 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1 debug1: SSH2_MSG_KEXINIT sent debug1: SSH2_MSG_KEXINIT received debug1: kex: server->client aes128-ctr hmac-md5 none debug1: kex: client->server aes128-ctr hmac-md5 none debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP debug1: SSH2_MSG_KEX_DH_GEX_INIT sent debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY debug1: Server host key: RSA 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48 The authenticity of host 'github.com (184.108.40.206)' can't be established. RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48. Are you sure you want to continue connecting (yes/no)? Host key verification failed.
One Solution collect form web for “Why can't ssh establish “the authenticity of host” for Github?”
Your ssh client does not know the RSA Fingerprint of the Github server yet, that’s why it asked you if you want to connect to it.
If you enter yes, the server’s fingerprint will be added to your client’s list of known hosts and it will not prompt you again unless the server’s finger print changes.