linux - 用于将连续整数分配为主机名的 Ansible 循环

Question

我是 Ansible 新手。我有以下更改远程服务器主机名的剧本:

---
- hosts: dbservers
  remote_user: testuser1
  become: yes
  become_method: sudo

  vars: 
    LOCAL_HOSTNAME: 'db01'
    LOCAL_DOMAIN_NAME: 'ansibletest.com'

  tasks:
    # Checks and removed the existing occurences of <IP hostname FQDN> from /etc/hosts
    - name: Remove occurences of the existing IP
      lineinfile: dest=/etc/hosts
                  regexp='{{ hostvars[item].ansible_default_ipv4.address }}'
                  state=absent
      when: hostvars[item].ansible_default_ipv4.address is defined
      with_items: "{{ groups['dbservers'] }}"

    #  Adds the IP in the format  <IP hostname FQDN> to /etc/hosts
    - name: Add the IP and hostname to the hosts file
      lineinfile: dest=/etc/hosts
                  regexp='.*{{ item }}$'
                  line="{{ hostvars[item].ansible_default_ipv4.address }} {{ LOCAL_HOSTNAME }} {{ LOCAL_HOSTNAME }}.{{ LOCAL_DOMAIN_NAME }}"
                  state=present
      when: hostvars[item].ansible_default_ipv4.address is defined
      with_items: "{{ groups['dbservers'] }}"

    - name: Remove HOSTNAME occurences from /etc/sysconfig/network
      lineinfile: dest=/etc/sysconfig/network
                  regexp='^HOSTNAME'
                  state=absent
      when: hostvars[item].ansible_default_ipv4.address is defined
      with_items: "{{ groups['dbservers'] }}"

    - name: Add new HOSTNAME to /etc/sysconfig/network
      lineinfile: dest=/etc/sysconfig/network
                  regexp='^HOSTNAME='
                  line="HOSTNAME={{ LOCAL_HOSTNAME }}.{{ LOCAL_DOMAIN_NAME }}"
                  state=present
      when: hostvars[item].ansible_default_ipv4.address is defined
      with_items: "{{ groups['dbservers'] }}"

    - name: Set up the hostname
      hostname: name={{ LOCAL_HOSTNAME }}.{{ LOCAL_DOMAIN_NAME }}

在此示例中，LOCAL_HOSTNAME 已被分配了值 db01。在这种情况下，dbservers 组只有一台服务器:

[dbservers]
192.168.1.93

但是，我还有另外 2 台指定为网络服务器的服务器:

[webservers]
192.168.1.95
192.168.1.96

[dbservers]
192.168.1.93

目的是将它们命名为web01.domain、web02.domain等。

根据 docs这似乎可以通过使用with_sequence来实现。

我的问题是，是否可以(在 Ansible 中)在循环中使用 2 个变量？类似于下面的伪代码:

i=1
for host in webservers:
   open host(/etc/hosts):
       add "IP<space>HOSTNAME{i}<space>"<space>"HOSTNAME{i}.FQDN"
       i++

这是否可以使用剧本来实现，还是我以错误的方式处理了这个问题？

Answer 1

首先生成索引主机名，将其定义为 hostfact，稍后使用它来填充其他服务器的主机文件。

- hosts: webservers
  gather_facts: no
  tasks:
    - set_fact:
        indexed_hostname: "{{ 'web{0:02d}'.format(play_hosts.index(inventory_hostname)+1) }}"

- hosts: dbservers
  gather_facts: no
  tasks:
    - debug:
        msg: "{{ hostvars[item].indexed_hostname }}"
      with_items: "{{ groups['webservers'] }}"

还有with_indexed_items这样的东西.