Use ansible to insert into etc hosts file

Question

I want to insert the following entry into the /etc/hosts file somehow using Ansible.

10.33.5.44 ip-10-33-5-44

Here, the schema is that the ip should have an alias corresponding to the IP, prefixed with ip- and where the dot . would be replaced by dash -.

But to get this IP, I can only think of doing the host command on a DNS name e.g.

host euwest2-test-box.company.com
> euwest2-test-box.company.com has address 10.33.5.44

Can anyone suggest how to get that to work? Is it possible?

Answer 1

您可以使用dig查找来实现此目的。然后在主机文件中添加以下行lineinefile。

请注意，该模块dig需要 Python 库dnspython才能运行。因此您可能还想与 Ansible 一起安装它。

因此，根据剧本：

- hosts: all
  gather_facts: no
  
  tasks:
    - package:
        name: py-dnspython
        state: present
    - lineinfile:
        path: /etc/hosts
        line: "{{ item }} ip-{{ item | replace('.', '-') }}"
      loop: "{{ lookup('dig', 'stackoverflow.com.').split(',') }}"

这给出了回顾：

PLAY [all] *********************************************************************************************

TASK [package] *****************************************************************************************
changed: [localhost]

TASK [lineinfile] **************************************************************************************
changed: [localhost] => (item=151.101.1.69)
changed: [localhost] => (item=151.101.65.69)
changed: [localhost] => (item=151.101.129.69)
changed: [localhost] => (item=151.101.193.69)

PLAY RECAP *********************************************************************************************
localhost                  : ok=2    changed=2    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

并相应地填充主机文件：

127.0.0.1   localhost
::1 localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
172.17.0.3  21eef8264e0c
151.101.1.69 ip-151-101-1-69
151.101.65.69 ip-151-101-65-69
151.101.129.69 ip-151-101-129-69
151.101.193.69 ip-151-101-193-69