CentOS 7 中安装并使用自动化工具 Ansible

柔光的暖阳◎ 2022-06-03 10:41 137阅读 0赞

Ansible是一款为类Unix系统开发的自由开源的配置和自动化工具。它用Python写成，类似于Chef和Puppet，但是有一个不同和优点是我们不需要在节点中安装任何客户端。它使用SSH来和节点进行通信。

**第一步： 使用yum安装Ansible**

rpm -ivh ansible-2.4.2.0-1.fc28.noarch.rpm

安装完成后，检查ansible版本：

[root@localhost soft]# ansible --version
    ansible 2.4.2.0
      config file = /etc/ansible/ansible.cfg
      configured module search path = [u'/root/.ansible/plugins/modules',u'/usr/share/ansible/plugins/modules']
      ansible python module location = /usr/lib/python2.7/site-packages/ansible
      executable location = /usr/bin/ansible
      python version = 2.7.5 (default, Aug  4 2017, 00:39:18) [GCC 4.8.5 20150623 (Red Hat 4.8.5-16)]

**第二步： 设置用于节点鉴权的SSH密钥**  
在Ansible服务端生成密钥，并且复制公钥到节点中。

[root@localhost soft]# ssh-keygen
    Generating public/private rsa key pair.
    Enter file in which to save the key (/root/.ssh/id_rsa):
    Enter passphrase (empty for no passphrase):
    Enter same passphrase again:
    Your identification has been saved in /root/.ssh/id_rsa.
    Your public key has been saved in /root/.ssh/id_rsa.pub.
    The key fingerprint is:
    SHA256:pvR6iWfppGPSFZlAqP35/6DEtGTvaMY64otThWoBTuk root@localhost.localdomain
    The key's randomart image is:
    +---[RSA 2048]----+
    |  .  o.          |
    |.o  . .          |
    |+. o . . o       |
    | Eo o . +        |
    |   o o..S.       |
    |  o ..oO.o       |
    | . . ..=*oo      |
    |  ..o *=@+ .     |
    |  .oo=+@+.o..    |
    +----[SHA256]-----+

使用ssh-copy-id命令来复制Ansible公钥到节点中。

root@localhost ~]# ssh-copy-id -i root@worker1
    /usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
    /usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
    /usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
    root@worker1's password:
    
    Number of key(s) added: 1
    
    Now try logging into the machine, with:   "ssh 'root@worker1'"
    and check to make sure that only the key(s) you wanted were added.

**第三步：为Ansible定义节点的清单**

文件 /etc/ansible/hosts 维护着Ansible中服务器的清单。

# This is the default ansible 'hosts' file.
    #
    # It should live in /etc/ansible/hosts
    #
    # - Comments begin with the '#' character
    # - Blank lines are ignored
    # - Groups of hosts are delimited by [header] elements
    # - You can enter hostnames or ip addresses
    # - A hostname/ip can be a member of multiple groups
    
    # Ex 1: Ungrouped hosts, specify before any group headers.
    
    ## green.example.com
    ## blue.example.com
    ## 192.168.100.1
    ## 192.168.100.10
    
    # Ex 2: A collection of hosts belonging to the 'webservers' group
    
    ## [webservers]
    ## alpha.example.org
    ## beta.example.org
    ## 192.168.1.100
    ## 192.168.1.110
    
    # If you have multiple hosts following a pattern you can specify
    # them like this:
    
    ## www[001:006].example.com
    
    # Ex 3: A collection of database servers in the 'dbservers' group
    
    ## [dbservers]
    ##
    ## db01.intranet.mydomain.net
    ## db02.intranet.mydomain.net
    ## 10.25.1.56
    ## 10.25.1.57
    
    # Here's another example of host ranges, this time there are no
    # leading 0s:
    [test-servers]
    worker1
    worker2
    
    ## db-[99:101]-node.example.com

**第四步：尝试在Ansible服务端运行命令**  
1.使用ping检查‘test-servers’或者ansible节点的连通性。

[root@localhost ansible]# ansible -m ping 'test-servers'
    worker1 | SUCCESS => {
        "changed": false,
        "ping": "pong"
    }
    worker2 | SUCCESS => {
        "changed": false,
        "ping": "pong"
    }

**执行shell命令**  
**1.检查Ansible节点的运行时间（uptime）**

[root@localhost ansible]# ansible -m command -a 'uptime' 'test-servers'
    worker2 | SUCCESS | rc=0 >>
     16:18:18 up  1:22,  3 users,  load average: 0.03, 0.04, 0.27
    
    worker1 | SUCCESS | rc=0 >>
     16:18:19 up  1:22,  3 users,  load average: 0.00, 0.02, 0.24

**2.检查节点的内核版本**

[root@localhost ansible]# ansible -m command -a 'uname -r' 'test-servers'
    worker1 | SUCCESS | rc=0 >>
    3.10.0-327.el7.x86_64
    
    worker2 | SUCCESS | rc=0 >>
    3.10.0-327.el7.x86_64

**3.给节点增加用户**

[root@localhost ansible]# ansible -m command -a 'useradd mark' 'test-servers'
    worker2 | SUCCESS | rc=0 >>
    
    
    worker1 | SUCCESS | rc=0 >>
    
    [root@localhost ansible]# ansible -m command -a 'grep mark /etc/passwd' 'test-servers'
    worker2 | SUCCESS | rc=0 >>
    mark:x:1000:1000::/home/mark:/bin/bash
    
    worker1 | SUCCESS | rc=0 >>
    mark:x:1000:1000::/home/mark:/bin/bash

**4.重定向输出到文件中**

[root@localhost ansible]# ansible -m command -a 'df -TH' 'test-servers' > /tmp/command-output.txt
    [root@localhost ansible]# cat /tmp/command-output.txt
    worker1 | SUCCESS | rc=0 >>
    文件系统       类型      容量  已用  可用 已用% 挂载点
    /dev/sda2      ext4       17G  2.6G   14G   17% /
    devtmpfs       devtmpfs  239M     0  239M    0% /dev
    tmpfs          tmpfs     249M     0  249M    0% /dev/shm
    tmpfs          tmpfs     249M  9.1M  240M    4% /run
    tmpfs          tmpfs     249M     0  249M    0% /sys/fs/cgroup
    /dev/sda1      ext4      199M  127M   58M   69% /boot
    /dev/sda5      ext4      2.1G  6.4M  2.0G    1% /home
    tmpfs          tmpfs      50M     0   50M    0% /run/user/0
    worker2 | SUCCESS | rc=0 >>
    文件系统       类型      容量  已用  可用 已用% 挂载点
    /dev/sda2      ext4       17G  2.6G   14G   17% /
    devtmpfs       devtmpfs  239M     0  239M    0% /dev
    tmpfs          tmpfs     249M     0  249M    0% /dev/shm
    tmpfs          tmpfs     249M  9.1M  240M    4% /run
    tmpfs          tmpfs     249M     0  249M    0% /sys/fs/cgroup
    /dev/sda1      ext4      199M  127M   58M   69% /boot
    /dev/sda5      ext4      2.1G  6.4M  2.0G    1% /home
    tmpfs          tmpfs      50M     0   50M    0% /run/user/0

**参考：**

> [http://www.linuxidc.com/Linux/2015-10/123801.htm][http_www.linuxidc.com_Linux_2015-10_123801.htm]

[http_www.linuxidc.com_Linux_2015-10_123801.htm]: http://www.linuxidc.com/Linux/2015-10/123801.htm