本地生成的的RSA密钥传需要传到远程主机相应用户家目录下的.ssh子目录下，注意该子目录的权限设置是有严格要求的：其所属用户当然是该用户，其权限应该是700, 即不允许其它用户进入并访问该目录；否则，无法自动登录的。
这种情况下，使用ssh 的-v参数显示详细消息大致如下：
$ ssh -v feng@myremote.host.net OpenSSH_5.3p1, OpenSSL 1.0.0-fips 29 Mar 2010 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to myremote.host.net [50.116.14.251] port 22. debug1: Connection established. debug1: identity file /home/feng/.ssh/identity type -1 debug1: identity file /home/feng/.ssh/id_rsa type 1 debug1: identity file /home/feng/.ssh/id_dsa type -1 debug1: Remote protocol version 2.0, remote software version OpenSSH_5.3 debug1: match: OpenSSH_5.3 pat OpenSSH* debug1: Enabling compatibility mode for protocol 2.0 debug1: Local version string SSH-2.0-OpenSSH_5.3 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: Host 'myremote.host.net' is known and matches the RSA host key. debug1: Found key in /home/feng/.ssh/known_hosts:8 debug1: ssh_rsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS debug1: SSH2_MSG_NEWKEYS received debug1: SSH2_MSG_SERVICE_REQUEST sent debug1: SSH2_MSG_SERVICE_ACCEPT received debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password debug1: Next authentication method: gssapi-keyex debug1: No valid Key exchange context debug1: Next authentication method: gssapi-with-mic debug1: Unspecified GSS failure. Minor code may provide more information Credentials cache file '/tmp/krb5cc_501' not found debug1: Unspecified GSS failure. Minor code may provide more information Credentials cache file '/tmp/krb5cc_501' not found debug1: Unspecified GSS failure. Minor code may provide more information debug1: Unspecified GSS failure. Minor code may provide more information debug1: Next authentication method: publickey debug1: Offering public key: /home/feng/.ssh/id_rsa debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password debug1: Offering public key: .ssh/id_rsa debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password debug1: Trying private key: /home/feng/.ssh/identity debug1: Trying private key: /home/feng/.ssh/id_dsa debug1: Next authentication method: password feng@myremote.host.net's password:
了解关于ssh免密码登录，强烈推荐这篇文章，基于ssh密钥对的自动登录原理及实际操作