ssh,公钥和私钥,远程复制

ssh,公钥和私钥,远程复制

1.openssh

是一个提供远程访问控制的软件

2.ssh 远程主机用户@远程主机ip地址
ssh root@172.25.254.1
The authenticity of host '172.25.254.1 (172.25.254.1)' can't be established.
ECDSA key fingerprint is 55:dd:43:ce:bf:94:dd:91:49:e7:97:29:63:3d:02:02.
Are you sure you want to continue connecting (yes/no)? yes
##建立安全传输key
root@172.25.254.1's password: ##密码输入没有回显
Last failed login: Sun Oct 11 16:56:29 CST 2015 from 172.25.254.206 on ssh:notty
There was 1 failed login attempt since the last successful login.
Last login: Sun Oct 11 16:55:46 2015 from 172.25.254.206
[root@foundation1 ~]# ###登陆成功
ctrl +d |logout
###退出
[root@foundation1 ~]# logout
Connection to 172.25.254.1 closed.

3.ssh的key认证

#######生成key###########
[test@foundation0 ~]$ ssh-keygen ###生成公钥和私钥的工具
Generating public/private rsa key pair.
Enter file in which to save the key (/home/test/.ssh/id_rsa):『enter』 ###指定加密字符保存文件，使用默认
Created directory '/home/test/.ssh'.
Enter passphrase (empty for no passphrase):
###密码，必须大于4位
Enter same passphrase again: 
Your identification has been saved in /home/test/.ssh/id_rsa.
Your public key has been saved in /home/test/.ssh/id_rsa.pub.
###确认密码
a5:4f:02:51:68:59:f4:e8:e3:c5:91:1f:6f:86:99:06 test@foundation0.ilt.example.com
key's randomart image is:
+--[ RSA 2048]----+
|      .*+        |
|      +. o .     |
|     .. . E .    |
|       o + + *   |
|        S + * +  |
|       . * . o   |
|        . .      |
|                 |
+-----------------+

[test@foundation0 .ssh]$ pwd
/home/test/.ssh ###生成密钥存放位置
[test@foundation0 .ssh]$ ls
id_rsa  id_rsa.pub ####id_rsa位私钥，id_rsa.pub位公钥

#####################使用key加密目标主机的目标用户############
[test@foundation0 ~]$  ssh-copy-id -i /home/test/.ssh/id_rsa.pub westos@172.25.254.100

The authenticity of host '172.25.254.100 (172.25.254.100)' can't be established.
ECDSA key fingerprint is eb:24:0e:07:96:26:b1:04:c2:37:0c:78:2d:bc:b0:08.
Are you sure you want to continue connecting (yes/no)? yes
/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
westos@172.25.254.100's password:

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'westos@172.25.254.100'"
and check to make sure that only the key(s) you wanted were added.

ssh-copy-id ####上传key的工具
-i ####指定使用的公钥
/home/test/.ssh/id_rsa.pub #####使用公钥的名称
westos ####被管理的目标用户
172.25.254.100 ####被管理用户所在主机的ip
authorized_keys ###此文件在目标用户加目录的.ssh中，这个文件就是目标用户被加密的标识，文件内容位公钥内容。

然后如果指定让哪个主机的哪个用户登录，就将 id_rsa（私钥，钥匙）传给那个主机的用户的.ssh下（前提是已经存在这个目录了）
scp id_rsa student@172.25.254.101:/home/student/.ssh/,之后[test@foundation0 .ssh]$ pwd
/home/test/.ssh ###生成密钥存放位置
[test@foundation0 .ssh]$ ls
id_rsa  id_rsa.pub ####id_rsa位私钥，id_rsa.pub位公钥

#####################使用key加密目标主机的目标用户############
[test@foundation0 ~]$  ssh-copy-id -i /home/test/.ssh/id_rsa.pub westos@172.25.254.100

The authenticity of host '172.25.254.100 (172.25.254.100)' can't be established.
ECDSA key fingerprint is eb:24:0e:07:96:26:b1:04:c2:37:0c:78:2d:bc:b0:08.
Are you sure you want to continue connecting (yes/no)? yes
/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
westos@172.25.254.100's password:

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'westos@172.25.254.100'"
and check to make sure that only the key(s) you wanted were added.

ssh-copy-id ####上传key的工具
-i ####指定使用的公钥
/home/test/.ssh/id_rsa.pub #####使用公钥的名称
westos ####被管理的目标用户
172.25.254.100 ####被管理用户所在主机的ip
authorized_keys ###此文件在目标用户加目录的.ssh中，这个文件就是目标用户被加密的标识，文件内容位公钥内容。
vimdiff authorized_keys id_rsa.pub 比较这两个文件有什么不同

如果让指定的某台主机能访问将id_rsa文件发送到给该主机的家目录的.ssh下就好：
scp id_rsa student@172.25.254.101:/home/student/Desktop
然后172.25.254.101这台主机的student用户就可以访问被加密的用户了
生成密钥的用户不一定是被加密的用户，可以在客户端生成公私钥远程给某个用户加密上锁

sshd服务的简单配置
vim /etc/ssh/sshd_config ###sshd服务的配置文件

48 PermitRootLogin yes|no ###是否允许root用户通过sshd的认证
78 PasswordAuthentication yes|no ###开启或关闭用户密码认证
AllowUsers student westos ###用户白名单，只允许在名单中出现的用户使用sshd服务
systemctl restart sshd ###从新加载配置
在服务端更改/etc/ssh/sshd_config可以禁止root登录，可以配置可登录的用户westos，然后在有密钥的客户端必须用ssh westos@172..... 才能登录，是敲的命令必须是westos@。。。

######################远程文件传输#####################
scp ##远程复制
scp file
user@ip:/directory ##上传文件
scp -r dir
user@ip:/directory ##长传目录
scp user@ip:/filename
/direcotry ##下载文件
scp -r user@ip:/directory
/direcotry ##下载目录

rsync ###远程同步（把文件归档，传输速度更快）
rsync file|direcotry user@ip:/directory
rsync user@ip:/directory /directory
-r ##同步目录
-l ##不忽略链接
-p ##不忽略特殊权限
-t ##不忽略时间戳
-g ##不忽略组信息
-o ##不忽略用户信息
-D ##不忽略设备文件
注意传输的原目录后如果不带/，是传输复制该目录下的子目录和文件不包含目录本身，
带/，则包含目录下的子文件与目录
sftp