rsync：SSH权限被拒绝（公钥）

我有一台服务器，可以通过SSH与我的密钥文件（例如）建立SSH连接id_rsa.pub。我在客户端和服务器端使用Debian。

我遵循了一个教程来禁用root身份验证和密码使用，以提高安全性（通过/etc/ssh/sshd/sshd_config在服务器上配置文件）。

到目前为止，我可以轻松地将rsync文件从计算机同步到服务器。

几天前，我使用了cron作业，为此，我不得不在服务器端重置我的root密码。

自那时以来，它一直是不可能的，我用rsync的SSH; 我收到以下消息：

[email protected]: Permission denied (publickey).
rsync: connection unexpectedly closed (0 bytes received so far)[sender]
rsync error: unexplained error (code 255) at io.c(235)[sender=3.1.3]

有一些类似的主题，但是我认为我的情况有所不同，因为我认为问题是由于在服务器上重置了密码所致。我也曾在Ask Ubuntu网站上问过一个问题，但我想也许这里的人在权限问题上更熟练。

我不知道如何解决该问题（我在终端命令中做了一些管理，但我不是计算机专家）。请问你能帮帮我吗？

仅供参考，请参阅本教程调整/etc/ssh/sshd_config不使用密码：

#Uncomment or add the following line. 
#This allows the server to give its DSA footprint in case of an ssh connection.
HostKey /etc/ssh/ssh/ssh_host_dsa_key

#Then set the next parameter to 20s (for example). 
#This is the time during which a connection without being logged in will be opened. 
#If we had kept the good old password technique, leave 2 or 3 minutes to type it, it's not too much. 
#But since we're using the key now, we'll be logged in immediately. #So we can really reduce the thing and put it down to 20 seconds for example.
LoginGraceTime 20s

#this is the maximum number of attempts before being thrown by the server.... 
#Since with the key, no possible error, you can put it to 1 possible test.
MaxAuthTries 1

#Then, we will tell the SSH server where the keys are and tell it that we will use them as an authentication method
PubkeyAuthentication yes
AuthorizedKeysFile.ssh/authorized_keys

#And of course, we'll disable all other authentication methods
RSAAuthentication no.
UsePAM no
KerberosAuthentication no
GSSAPIA Authentication no.
PasswordAuthentication no

#Then, we will tell that we only allow users of the sshusers group (for more security)
AllowGroups sshusers

#The MaxStartups setting indicates the number of un-authenticated ssh connections you can launch at the same time. 
#2 is more than enough, knowing that with the keys, it's instantaneous.
MaxStartups 2