我过去4-5小时一直试图通过RSA密钥设置一个带SSH身份验证的Ubuntu服务器，但是我无法让它工作。谷歌没有任何运气。
我正在使用SSH-2.0-OpenSSH_7.2p2运行Ubuntu 16.04.3服务器。刚刚重新安装了服务器。
我确保将~/.ssh文件夹的权限设置为700，将/.ssh/authorized_keys设置为600
密钥由Puttygen（RSA 2048位）制作，我将其格式化为ssh-rsa <long random string> comment，然后将其添加到/home/user/.ssh/authorized_keys
这是我尝试使用密钥登录时遇到的错误：
login as: user
Server refused our key
这是我从sshd调试日志中获得的错误消息。
Feb 27 23:23:21 CSGO6 sshd [1439]：debug1：无法打开授权密钥＆＃39; /home/user/.ssh/authorized_keys'：权限被拒绝
有没有人理解为什么sshd没有对authorized_keys文件的许可？
这是sshd_config
# Package generated configuration file
# See the sshd_config(5) manpage for details
# What ports, IPs and protocols we listen for Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
HostKey /etc/ssh/ssh_host_ecdsa_key
HostKey /etc/ssh/ssh_host_ed25519_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes
# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 1024
# Logging
SyslogFacility AUTH
LogLevel DEBUG3
# Authentication:
LoginGraceTime 120
PermitRootLogin prohibit-password
StrictModes yes
RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys
# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for
RhostsRSAAuthentication
#IgnoreUserKnownHosts yes
# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no
# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no
# Change to no to disable tunnelled clear text passwords
#PasswordAuthentication yes
# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no
#MaxStartups 10:30:60
#Banner /etc/issue.net
# Allow client to pass locale environment variables
AcceptEnv LANG LC_*
Subsystem sftp /usr/lib/openssh/sftp-server
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes
user@CSGO6:~$ # Package generated configuration file
user@CSGO6:~$ # See the sshd_config(5) manpage for details
user@CSGO6:~$
user@CSGO6:~$ # What ports, IPs and protocols we listen for
user@CSGO6:~$ Port 22
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
HostKey /etc/ssh/ssh_host_ecdsa_key
HostKey /etc/ssh/ssh_host_ed25519_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes
# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 1024
# Logging
SyslogFacility AUTH
LogLevel DEBUG3
# Authentication:
LoginGraceTime 120
PermitRootLogin prohibit-password
StrictModes yes
RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys
# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for
RhostsRSAAuthentication
#IgnoreUserKnownHosts yes
# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no
# Change to yes to enable challenge-response passwords (beware issues with
# some PAM modules and threads)
ChallengeResponseAuthentication no
# Change to no to disable tunnelled clear text passwords
#PasswordAuthentication yes
# Kerberos options
#KerberosAuthentication no
#KerberosGetAFSToken no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no
#MaxStartups 10:30:60
#Banner /etc/issue.net
# Allow client to pass locale environment variables
AcceptEnv LANG LC_*
Subsystem sftp /usr/lib/openssh/sftp-server
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes
以下是ls -la文件夹和.ssh文件的authorized_keys
user@CSGO6:~$ ls -la /home/user/.ssh/
total 12
drwx------ 2 user user 4096 Feb 27 23:39 .
drwxr-xr-x 5 user user 4096 Feb 27 23:14 ..
-rw------- 1 root root 802 Feb 27 23:39 authorized_keys
顺便说一句，使用相同的rsa-key来ssh到我的覆盆子pi是没问题的。
答案 0 :(得分：0)
我终于成功了。
这就是我所做的： 我再次添加了密钥，但是这次通过scp（使用putty程序pscp.exe）而不是在使用SSH会话登录服务器时粘贴密钥。
然后我更改了密钥以匹配OpenSSH服务器所需的正确语法，将其重命名为authorized_keys2并将权限更改为600.尝试使用我的密钥和putila登录putty。
我很遗憾不知道为什么现在突然起作用，但我很高兴。