Putty connection to centos is slow

The centos minimal image under vmware is used. When developing, the connection with putty is very slow, more than a minute.

solution:

禁用GSSAPI认证有两个方式：客户端和服务端
直接配置你ssh客户端的文件/etc/ssh/ssh_config来达到永久解决这个问题：
客户端禁用GSSAPIAuthentication
vi /etc/ssh/ssh_config
修改为GSSAPIAuthentication no
 
服务端禁用GSSAPIAuthentication
vi /etc/ssh/sshd_config
修改为GSSAPIAuthentication no
修改为UseDNS no
 
最后重启SSH服务：service sshd restart