我有一个 CentOS 7 系统，当我使用 putty 或 ssh 登录时，在我收到密码提示之前有很长的延迟。我跑了 ssh -v ，我发现它达到了这个：
debug1: ssh_ecdsa_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
然后它在那里坐了 1-2 分钟，然后这个输出爆炸了：
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
No Kerberos credentials available
debug1: Unspecified GSS failure. Minor code may provide more information
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