centOS 구글 otp 적용

#google otp 설치 

sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm
sudo yum install google-authenticator

#하기내용 제일 하단에 추가
sudo vi /etc/pam.d/sshd

auth    required    pam_google_authenticator.so nullok

#하기 설정 다음과같이 변경
sudo vi /etc/ssh/sshd_config

PermitEmptyPasswords no
PasswordAuthentication no
ChallengeResponseAuthentication yes
UsePAM yes

#sshd 재시작
systemctl restart sshd

#google authenticator 인증파일생성
google-authenticator
#전부 y

#설치가 완료되면 상단에 qr 링크가 생성됨