Linux ssh无密码登录不起作用？

Question

bharathi-1397@bharathi-1397:~$ ssh-keygen 
Generating public/private rsa key pair. 
Enter file in which to save the key (/home/local/bharathi-1397/.ssh/id_rsa): 
/home/local/bharathi-1397/.ssh/id_rsa already exists. 
Overwrite (y/n)? y 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/local/bharathi-1397/.ssh/id_rsa. 
Your public key has been saved in /home/local/bharathi-1397/.ssh/id_rsa.pub. 
The key fingerprint is: 
de:e3:e5:f6:a3:8e:83:76:f0:7d:d6:e1:b3:d6:cc:93 bharathi-1397@bharathi-1397 
The key's randomart image is: 
+--[ RSA 2048]----+ 
|     | 
|     | 
|     | 
|     | 
|  S  | 
|  ...  . | 
|  .+o.. .++| 
|  o.+=o +E=| 
|  . .o++=oo+| 
+-----------------+ 

接下来，我从.ssh/id_rsa.pub复制内容并存储在远程机器中。

bharathikannan.r@172.20.2.7:~$ mkdir .ssh 
bharathikannan.r@172.20.2.7:~$ vi authorized_keys 

将复制的内容粘贴到authorized_keys中，但下次尝试登录时会问密码为什么？ ssh bharathikannan.r@172.20.2.7 bharathikannan.r@172.20.2.7的密码：

为什么要问密码？ 。我按照正确的步骤。我不知道它为什么要求密码？

ssh -v bharathikannan.r@172.20.2.7 
OpenSSH_5.8p1 Debian-7ubuntu1, OpenSSL 1.0.0e 6 Sep 2011 
debug1: Reading configuration data /etc/ssh/ssh_config 
debug1: Applying options for * 
debug1: Connecting to integ-build3 [192.168.5.173] port 22. 
debug1: Connection established. 
debug1: identity file /home/local/bharathi-1397/.ssh/id_rsa type 1 
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048 
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048 
debug1: identity file /home/local/bharathi-1397/.ssh/id_rsa-cert type -1 
debug1: identity file /home/local/bharathi-1397/.ssh/id_dsa type -1 
debug1: identity file /home/local/bharathi-1397/.ssh/id_dsa-cert type -1 
debug1: identity file /home/local/bharathi-1397/.ssh/id_ecdsa type -1 
debug1: identity file /home/local/bharathi-1397/.ssh/id_ecdsa-cert type -1 
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.3 
debug1: match: OpenSSH_4.3 pat OpenSSH_4* 
debug1: Enabling compatibility mode for protocol 2.0 
debug1: Local version string SSH-2.0-OpenSSH_5.8p1 Debian-7ubuntu1 
debug1: SSH2_MSG_KEXINIT sent 
debug1: SSH2_MSG_KEXINIT received 
debug1: kex: server->client aes128-ctr hmac-md5 none 
debug1: kex: client->server aes128-ctr hmac-md5 none 
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent 
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP 
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent 
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY 
debug1: Server host key: RSA 66:3e:67:25:65:22:f0:70:3d:e3:ce:3b:14:49:7e:76 
debug1: Host '172.20.2.7' is known and matches the RSA host key. 
debug1: Found key in /home/local/bharathi-1397/.ssh/known_hosts:5 
debug1: ssh_rsa_verify: signature correct 
debug1: SSH2_MSG_NEWKEYS sent 
debug1: expecting SSH2_MSG_NEWKEYS 
debug1: SSH2_MSG_NEWKEYS received 
debug1: Roaming not allowed by server 
debug1: SSH2_MSG_SERVICE_REQUEST sent 
debug1: SSH2_MSG_SERVICE_ACCEPT received 
debug1: Authentications that can continue: publickey,gssapi-with-mic,password 
debug1: Next authentication method: publickey 
debug1: Offering RSA public key: /home/local/bharathi-1397/.ssh/id_rsa 
debug1: Authentications that can continue: publickey,gssapi-with-mic,password 
debug1: Trying private key: /home/local/bharathi-1397/.ssh/id_dsa 
debug1: Trying private key: /home/local/bharathi-1397/.ssh/id_ecdsa 
debug1: Next authentication method: password 
bharathikannan.r@172.20.2.7's password: 

Answer 1

根据您的描述，您在家中创建了.ssh目录，然后在同一目录（您的家中，不在〜/ .ssh /中）创建.authorized_keys文件。请确保文件位于正确的位置。

此外，下面的命令可以设置你没有所有的麻烦：

user@host:~$ ssh-copy-id user@otherhost 

希望有所帮助。

Answer 2

这是要求输入密码，因为您还没有告诉客户机使用哪个密钥。

你可以做两个方面，这一个：

1）当您终端到你的远程机器上，使用以下命令：

ssh -i /path/to/your/privatekey user@host

2）在客户机上创建文件~/.ssh/config并插入以下内容：

Host your.hostname.tld 
IdentityFile /path/to/your/privatekey 

如果您想要使用多个不同的密钥，方法1是非常好的。每次连接到给定主机时，方法2都会自动实现自动。

Answer 3

这两个系统上的.ssh dir应该是700。

drwx------ .ssh 

Answer 4

您可能没有〜/ .ssh目录或没有.ssh/authorized_keys文件。请注意，只需手动创建〜/ .ssh/authorized_keys文件，就可以轻松地获得其中一个权限错误。

chmod 700 ~/.ssh 
chmod 600 ~/.ssh/id_rsa 
chmod 644 ~/.ssh/id_rsa.pub 
chmod 644 ~/.ssh/authorized_keys 
chmod 644 ~/.ssh/known_hosts 
restorecon -R ~/.ssh 

真正的疑难杂症是最后一个，SELINUX（这是我偶然发现的，我总是这么做）。您可以随时尝试将其设置为宽容和/或检查audit.log。

# ll -Z ~/.ssh/authorized_keys 
-rw-r--r--. root root unconfined_u:object_r:admin_home_t:s0 /root/.ssh/authorized_keys 
# restorecon -R ~/.ssh 
# ll -Z ~/.ssh/authorized_keys 
-rw-r--r--. root root unconfined_u:object_r:ssh_home_t:s0 /root/.ssh/authorized_keys 

做不到这一切登录到目标机器并创建

ssh-keygen