Centos SSH login slow solution

# 用root用户或者有管理员权限用户
sudo echo 'UseDNS  no'  >> /etc/ssh/sshd_config

# 查看下增加的配置 （可以不看） 去除了注释与空行

sudo cat /etc/ssh/sshd_config |grep -v '#' | grep -v '^$'


HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_ecdsa_key
HostKey /etc/ssh/ssh_host_ed25519_key
SyslogFacility AUTHPRIV
AuthorizedKeysFile      .ssh/authorized_keys
PasswordAuthentication yes
ChallengeResponseAuthentication no
GSSAPIAuthentication yes
GSSAPICleanupCredentials no
UsePAM yes
X11Forwarding yes
AcceptEnv LANG LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES
AcceptEnv LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT
AcceptEnv LC_IDENTIFICATION LC_ALL LANGUAGE
AcceptEnv XMODIFIERS
Subsystem       sftp    /usr/libexec/openssh/sftp-server
UseDNS no

# 重启SSH服务
sudo systemctl restart sshd

Because of the reverse verification DNS problem, it may take about 10 seconds to log in locally. After removing it, log in in seconds.