2023/01/17 10:32:39 ssh: handshake failed: ssh: unable to authenticate, attempted methods [none publickey], no supported methods remain
SSH public key 가 제대로 동작하지 않는 오류가 발생하였다.
$ sudo tail -f /var/log/auth.log
Jan 17 11:35:46 yologa-dev-authentication-api sudo: pam_unix(sudo:session): session opened for user root(uid=0) by kyb062666(uid=1001)
Jan 17 11:36:28 yologa-dev-authentication-api sudo: pam_unix(sudo:session): session closed for user root
Jan 17 11:37:40 yologa-dev-authentication-api sshd[9297]: Invalid user kyb062666@gmail.com from 13.64.13.86 port 7216
Jan 17 11:37:40 yologa-dev-authentication-api sshd[9297]: Connection closed by invalid user kyb062666@gmail.com 13.64.13.86 port 7216 [preauth]
Jan 17 11:39:44 yologa-dev-authentication-api sshd[9307]: Unable to negotiate with 1.34.133.138 port 33657: no matching host key type found. Their offer: ssh-rsa,ssh-dss [preauth]
Jan 17 11:40:20 yologa-dev-authentication-api sshd[9309]: Unable to negotiate with 118.200.47.94 port 60614: no matching host key type found. Their offer: ssh-rsa,ssh-dss [preauth]
Jan 17 11:44:03 yologa-dev-authentication-api sshd[9329]: Unable to negotiate with 118.38.80.190 port 63841: no matching host key type found. Their offer: ssh-rsa,ssh-dss [preauth]
Jan 17 11:51:48 yologa-dev-authentication-api sshd[9364]: Unable to negotiate with 90.186.201.118 port 52529: no matching host key type found. Their offer: ssh-rsa,ssh-dss [preauth]
Jan 17 11:52:21 yologa-dev-authentication-api sudo: kyb062666 : TTY=pts/0 ; PWD=/etc/ssh ; USER=root ; COMMAND=/usr/bin/tail -f /var/log/auth.log
Jan 17 11:52:21 yologa-dev-authentication-api sudo: pam_unix(sudo:session): session opened for user root(uid=0) by kyb062666(uid=1001
https://github.com/appleboy/ssh-action/issues/80#issuecomment-943116137
이전에는 600 으로 설정되어 있던 authorized_keys 파일을 700 으로 설정한다.
https://github.com/appleboy/ssh-action/issues/80#issuecomment-953889379
→ 욜로가 서버에서는 따로 설정하지 않아도 제대로 동작하였고, 욜로가 인증 서버에서는 위의 설정을 추가해도 동작하지 않음
우분투 20.04 혹은 그 이후의 버전에서는 RSA 알고리즘을 사용해야 한다. SSH 접속할 때 RSA 알고리즘으로 만들어진 키를 사용한다는 설정을 추가하자.
/etc/ssh/sshd_config
CASignatureAlgorithms +ssh-rsa
https://github.com/appleboy/ssh-action#if-you-are-using-openssh
→ 욜로가 서버에서는 따로 설정하지 않아도 제대로 동작하였고, 욜로가 인증 서버에서는 위의 설정을 추가해도 동작하지 않음