問題

已經將主機的公鑰id_rsa.pub追加到了遠端主機的authorized_keys檔案中，且檔案許可權均為 600
但是仍然無法免密登入，只能使用密碼登入

日誌

# tail /var/log/secure
Dec  7 15:54:17 image sshd[5558]: Disconnected from 10.171.122.85 port 38000
Dec  7 15:54:17 image sshd[5558]: pam_unix(sshd:session): session closed for user root
Dec  7 15:54:20 image sshd[5579]: reprocess config line 50: Deprecated option RSAAuthentication
Dec  7 15:54:20 image sshd[5579]: Authentication refused: bad ownership or modes for directory /root
Dec  7 15:54:36 image sshd[5579]: Accepted password for root from 10.171.122.85 port 38006 ssh2
Dec  7 15:54:36 image sshd[5579]: pam_unix(sshd:session): session opened for user root by (uid=0)
Dec  7 15:54:37 image sshd[5579]: Received disconnect from 10.171.122.85 port 38006:11: disconnected by user
Dec  7 15:54:37 image sshd[5579]: Disconnected from 10.171.122.85 port 38006
Dec  7 15:54:37 image sshd[5579]: pam_unix(sshd:session): session closed for user root
Dec  7 15:57:01 image sshd[5905]: reprocess config line 50: Deprecated option RSAAuthentication
Dec  7 15:57:01 image sshd[5905]: Accepted publickey for root from 10.171.122.85 port 38106 ssh2: RSA SHA256:1A8dDgEnM7OQxIySYUWzipuF6boKrYlT2zjYFjyA1sE
Dec  7 15:57:01 image sshd[5905]: pam_unix(sshd:session): session opened for user root by (uid=0)
 

解決

使用者家目錄許可權被篡改為非使用者屬組，需要更改為指定的使用者許可權，且使用者目錄組許可權不能有 W 許可權

chmod g-w /home/user
chmod 700 ./.ssh 
chmod 600 ~/.ssh/authorized_keys

-PS

linux下免密認證登入失敗原因總結