1. 以管理员身份登录

  2. 给文件授权，以完成sshd 服务的安装

    $ chmod +r /etc/group
$ chmod +r /etc/passwd
$ chmod +rwx /var

  3. 安装 sshd 服务

    $ ssh-host-config 
Query: Should privilege separation be used? (yes/no) yes
Query: (Say "no" if it is already installed as a service) (yes/no) yes
Query: Enter the value of CYGWIN for the daemon: [ntsec] ntsec
Query: Do you want to use a different name? (yes/no) no

    不同版本的sshd问题不一样，假如有其他提问自己看着办

  4. 使用 windows 用户本地认证，即使用windows 的用户名和密码登录

(这一步比较关键，之前按照Hadoop开发者的资料操作，没有这个步骤，导致了我的CYGWIN sshd服务启动不起来，老是提示“一些服务自动停止,如果他们没什么可做的......”)

//把windows的用户导入到cygwin下,在安装cygwin的过程中，安装程序会自动执行这个命令的。由于windows下 没有root用户，所以cygwin一般把system和admin的用户，作为root来用
$ mkpasswd -l > /etc/passwd
$ mkgroup -l > /etc/group

  1. 启动

    $ cygrunsrv --start cygsshd
$ cygrunsrv --stop cygsshd

  2. 客户端登录(假设服务器地址为192.168.1.100)

    $ ssh administrator@192.168.1.100

常见问题：

  1. Q: cygrunsrv -S cygsshd不能启动，报告
    cygrunsrv: Error starting a service: QueryServiceStatus: Win32 error 1062

A: 很可能是/var/log的权限设置不正确。首先执行 mkpasswd 和 mkgroup 重新生成权限信息，再删除sshd服务，重新配置：

$ mkpasswd -l > /etc/passwd
$ mkgroup -l > /etc/group
$ cygrunsrv -R cygsshd
$ ssh-host-config -y
$ cygrunsrv -S cygsshd

$ net start sshd
发生系统错误 1069 --- 表示由于登录失败而无法启动服务
解决方法：在cmd中输入services.msc即可打开windows的服务，在CYGWIN sshd服务中把密码改对就可以了。
（在上面配置ssh的过程中我的用户名是：root 密码是：123456）
如报错服务不存在，确认服务名称
cygrunsrv: Error removing a service: OpenService: Win32 error 1060

  1. Q: 客户端连接时提示服务器密钥(ssh-rsa)不一致

    A: 应该是客户端以前连接时记录的服务器密钥跟新的不一致：
在客户端的cygwin的 /home/xxx(用户名，比如Administrator)/.ssh/known_hosts文件中找到服务器地址所对应的一行，删除掉，重新连接

  2. Win7下Cygwin中，使用ssh localhost命令，出现Connection closed by127.0.0.1的问题

    解决方案：
1）开始——运行——services.msc
2）右键CYGWINsshd——属性——登录选项卡——选择“此账户”——浏览——高级——立即查找——选择你的账户名（必须为管理员权限）——输入密码（必须要有，空密码不接受）——确定。
3）重启CYGWINsshd服务即可。这样就以你的账户的名义启动了这个服务。然后ssh localhost成功。

  3. cygwin登陆命令

    chdir D:\cygwin64\bin
bash --login -i
这篇文章主要是为我在win7（64位）下搭建hadoop环境所准备的。首先参照在cygwin使用总结这篇文章在cygwin中安装所必须得软件包，然后如下进行操作：

sony@sony-VAIO~ $ ssh-host-config

*** Info: Generating /etc/ssh_host_key
*** Info: Generating /etc/ssh_host_rsa_key
*** Info: Generating /etc/ssh_host_dsa_key
*** Info: Generating /etc/ssh_host_ecdsa_key
*** Info: Creating default /etc/ssh_config file
*** Info: Creating default /etc/sshd_config file
*** Info: Privilege separation is set to yes by default since OpenSSH 3.3.
*** Info: However, this requires a non-privileged account called 'sshd'.
*** Info: For more info on privilege separation read /usr/share/doc/openssh/READ
ME.privsep.
*** Query: Should privilege separation be used? (yes/no) no
*** Info: Updating /etc/sshd_config file

*** Query: Do you want to install sshd as a service?
*** Query: (Say "no" if it is already installed as a service) (yes/no) yes
*** Query: Enter the value of CYGWIN for the daemon: netsec] netsec
*** Info: On Windows Server 2003, Windows Vista, and above, the
*** Info: SYSTEM account cannot setuid to other users -- a capability
*** Info: sshd requires.  You need to have or to create a privileged
*** Info: account.  This script will help you do so.

*** Info: You appear to be running Windows XP 64bit, Windows 2003 Server,
*** Info: or later.  On these systems, it's not possible to use the LocalSystem
*** Info: account for services that can change the user id without an
*** Info: explicit password (such as passwordless logins [e.g. public key
*** Info: authentication] via sshd).

*** Info: If you want to enable that functionality, it's required to create
*** Info: a new account with special privileges (unless a similar account
*** Info: already exists). This account is then used to run these special
*** Info: servers.

*** Info: Note that creating a new user requires that the current account
*** Info: have Administrator privileges itself.

*** Info: No privileged account could be found.

*** Info: This script plans to use 'cyg_server'.
*** Info: 'cyg_server' will only be used by registered services.
*** Query: Do you want to use a different name? (yes/no) yes
*** Query: Enter the new user name: sony
*** Query: Reenter: sony

*** Warning: Privileged account 'sony' was specified,
*** Warning: but it does not have the necessary privileges.
*** Warning: Continuing, but will probably use a different account.
*** Warning: The specified account 'sony' does not have the
*** Warning: required permissions or group memberships. This may
*** Warning: cause problems if not corrected; continuing...
*** Query: Please enter the password for user 'sony':
*** Query: Reenter:


*** Info: The sshd service has been installed under the 'sony'
*** Info: account.  To start the service now, call `net start sshd' or
*** Info: `cygrunsrv -S sshd'.  Otherwise, it will start automatically
*** Info: after the next reboot.

*** Info: Host configuration finished. Have fun!
 $ net start sshd
发生系统错误 1069 --- 表示由于登录失败而无法启动服务
解决方法：在cmd中输入services.msc即可打开windows的服务，在服务中把密码改对就可以了。
（在上面配置ssh的过程中我的用户名是：sony 密码是：123456）

sshd服务装成功如下：

sony@sony-VAIO ~ $ net start sshd
CYGWIN sshd 服务正在启动 .
CYGWIN sshd 服务已经启动成功
接下来是配置无密码登陆：

sony@sony-VAIO ~ $ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/sony/.ssh/id_rsa):
Created directory '/home/sony/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/sony/.ssh/id_rsa.
Your public key has been saved in /home/sony/.ssh/id_rsa.pub.
The key fingerprint is:
e8:38:5e:e3:bb:cf:76:03:61:5f:f2:68:ed:a3:49:db sony@sony-VAIO
The key's randomart image is:
+--[ RSA 2048]----+
|                 |
|                 |
|                 |
|       .o . .    |
|      ..So *     |
|     o  . + o    |
|    o +  o..     |
|   . + o..o+o    |
|    . +=o.+oE.   |
+-----------------+

sony@sony-VAIO ~ $ cd .ssh/

sony@sony-VAIO ~/.ssh $ ls
id_rsa  id_rsa.pub

sony@sony-VAIO ~/.ssh $ cp id_rsa.pub authorized_keys

sony@sony-VAIO ~/.ssh $ ls
authorized_keys  id_rsa  id_rsa.pub
验证如下：

sony@sony-VAIO ~/.ssh $ ssh localhost
The authenticity of host 'localhost (::1)' can't be established.
ECDSA key fingerprint is 5f:21:b1:24:80:92:f6:af:3e:e3:a8:f9:cb:a4:4f:ec.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'localhost' (ECDSA) to the list of known hosts.

sony@sony-VAIO ~ $ who
sony     tty0         2011-11-25 15:42 (::1)