Configuration method of ansible list file, configuration of configuration file, usage of temporary command

Configuration method of ansible list file, configuration of configuration file, usage of temporary command

1. Build ansible list

1. List of definitions

Inventories define a batch of hosts that Ansible will manage. These hosts can also be assigned into groups for centralized management. Groups can contain subgroups, and hosts can be members of multiple groups. A manifest can also set variables that apply to the hosts and groups it defines.

There are two ways to define a list:

• Static Host List: Text File Definitions
• Dynamic Host Inventory: Generated by script or other program as needed using an external information provider

2. Use a static list to specify managed hosts

Each section begins with the host group name enclosed in square brackets. This is followed by the hostname or IP address of each managed host in the group, one per line.

[root@localhost ~]# vim /etc/ansible/hosts
## [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

3. Verification checklist

[root@localhost ~]# vim /etc/ansible/hosts
green.example.com
blue.example.com
192.168.100.1
192.168.100.10		//取消此四行的注释

//验证green主机是否存在于清单
[root@localhost ~]# ansible green.example.com --list-hosts
  hosts (1):
    green.example.com
    
//列出清单中的所有主机
[root@localhost ~]# ansible all --list-hosts
  hosts (4):
    green.example.com
    blue.example.com
    192.168.100.1
    192.168.100.10

[root@localhost ~]# vim /etc/ansible/hosts
[webservers]
alpha.example.org
beta.example.org
192.168.1.100
192.168.1.110		//取消此主机组的注释

//列出指定主机组
[root@localhost ~]# ansible webservers --list-hosts
  hosts (4):
    alpha.example.org
    beta.example.org
    192.168.1.100
    192.168.1.110

If the inventory contains hosts and hostgroups with the same name, the ansible command will display a warning and target the host. Host groups are ignored.

[root@localhost ~]# vim /etc/ansible/hosts
[webservers]
webservers		//添加一个和主机组相同名称的主机
alpha.example.org
beta.example.org
192.168.1.100
192.168.1.110


//会列出主机并警告
[root@localhost ~]# ansible webservers --list-hosts
[WARNING]: Found both group and host with same name: webservers
  hosts (1):
    webservers

4. Override the location of the manifest file

The /etc/ansible/hosts file is considered the default static inventory file for the system. However, it is common practice not to use this file, but to define a different location for the inventory file in the Ansible configuration file.

//修改默认清单文件位置
[root@localhost ~]# cd /etc/ansible/
[root@localhost ansible]# touch inventory
[root@localhost ansible]# vim ansible.cfg 
inventory      = /etc/ansible/inventory		//取消注释并修改指定位置

5. Build checklist

//写入内容
[root@localhost ansible]# vim inventory 
192.168.183.137

[webservers]
192.168.183.135

192.168.183.136

//列出默认清单文件中的所有受管主机
[root@localhost ansible]# ansible all  --list-hosts
  hosts (3):
    192.168.183.137
    192.168.183.135
    192.168.183.136
    
//列出不属于任何主机组的受管主机
[root@localhost ansible]# ansible ungrouped --list-hosts
  hosts (1):
    192.168.183.137
    
//列出属于某组的受管主机
[root@localhost ansible]# ansible webservers --list-hosts
  hosts (2):
    192.168.183.135
    192.168.183.136

Two, ansible configuration file

Some common parameters in Ansible configuration files

[root@localhost ~]# vim /etc/ansible/ansible.cfg
······
[defaults]

# some basic default values...

inventory      = /etc/ansible/inventory
#library        = /usr/share/my_modules/
#module_utils   = /usr/share/my_module_utils/
#remote_tmp     = ~/.ansible/tmp
#local_tmp      = ~/.ansible/tmp
#plugin_filters_cfg = /etc/ansible/plugin_filters.yml
#forks          = 5
#poll_interval  = 15
#sudo_user      = root
#ask_sudo_pass = True
#ask_pass      = True
#transport      = smart
#remote_port    = 22
#module_lang    = C
#module_set_locale = False

······

parameter	effect
inventory	Defines Ansible's default host configuration file, which defaults to /etc/ansible/hosts
library	Defines the location of Ansible's default search module, which defaults to the /etc/ansible/my_modules/ directory
remote_tmp	Ansible remote execution temporary files are defined
pattern	The host that Ansible communicates with is defined, and the parameter defaults to *, which means communicating with all hosts
forks	Defines the number of parallel processes for Ansible, the default is 5
poll_interval	Defines the polling frequency or polling interval
sudo_user	Defines the sudo remote execution username
ask_sudo_pass	Defines whether a password is required to use sudo
ask_pass	Defines whether a password is required
transport	Defines the communication mechanism of Ansible
remote_port	Defines the communication port of Ansible, the default is 22
module_lang	Defines the language for communication between Ansible modules and systems
gathering	Control the collection of facts information
roles_path	Used to search roles in Ansible
host_key_checking	for checking the host key
sudo_exe	Used to specify sudo to execute commands remotely
sudo_flags	Used to pass parameters other than sudo
timeout	Used to set the SSH timeout
remote_user	Used to set the remote login username
log_path	Used to specify the Ansible log file, by default /var/log/ansible.log
module_name	Used to specify the execution module of Ansible by default, the default is command
executable	Used to specify the shell environment for Ansible execution
hash_behavior	Used to specify specific priority override variables
jinjia2_extensions	Set to allow the jinjia2 extension module to be enabled
private_key_file	Used to specify the storage location of the private key file
display_skipped_hosts	Used to display the status of any skipped tasks
system_warnings	Used to disable the system from displaying ansible potential problem warnings
deprecation_warnings	Playbook output disables "deprecated" warnings
command_warnings	The command module Ansible issues warnings by default
pipelining	Used to enable pipe SSH channel optimization

3. Usage of interim orders

One of the simplest temporary commands uses the ping module. This module does not perform an ICMP ping , but instead checks whether a Python-based module can be run on the managed host. For example, the following temporary command determines whether all managed hosts in the inventory can run standard modules:

[root@localhost ~]# vim /etc/ansible/inventory 
web1 ansible_user=root ansible_password=runtime
[root@localhost ~]# vim /etc/hosts
192.168.183.140 web1
[root@localhost ~]# ssh web1
[root@localhost ~]# ansible web1 -m ping
web1 | SUCCESS => {
    
    
    "ansible_facts": {
    
    
        "discovered_interpreter_python": "/usr/libexec/platform-python"
    },
    "changed": false,
    "ping": "pong"
}

Ansible common modules

Module category	module
file module	copy: Copies a local file to a managed host file: Sets the permissions and other attributes of a file lineinfile: Ensures whether a specific line is in a file or not synchronize: Synchronizes content using rsync
package module	package：使用操作系统本机的自动检测软件包管理器管理软件包 yum：使用yum管理软件包 apt：使用APT管理软件包 dnf：使用dnf管理软件包 gem：管理Ruby gem pip：从PyPI管理Python软件包
系统模块	firewalld：使用firewalld管理防火墙 reboot：重启计算机 service：管理服务 user：添加、删除和管理用户帐户
Net Tools模块	get_url：通过HTTP、HTTPS或FTP下载文件 nmcli：管理网络 uri：与Web服务交互

临时命令使用user模块来确保runtime用户存在于web1上并且其UID为4000：

[root@localhost ~]# ansible web1 -m user -a 'name=runtime uid=4000 state=present'
web1 | CHANGED => {
    
    
    "ansible_facts": {
    
    
        "discovered_interpreter_python": "/usr/libexec/platform-python"
    },
    "changed": true,
    "comment": "",
    "create_home": true,
    "group": 4000,
    "home": "/home/runtime",
    "name": "runtime",
    "shell": "/bin/bash",
    "state": "present",
    "system": false,
    "uid": 4000
}
[root@localhost ~]# ansible all -a 'id runtime'
web1 | CHANGED | rc=0 >>
uid=4000(runtime) gid=4000(runtime) groups=4000(runtime)