Ansible Increment Number on each node

Question

I'am trying to define the jvmroute in server.xml of tomcat by naming it node0x. To do that i find i playbook with increment_number with anisble_facts

`     - name: set number node
      become: yes
      become_method: sudo
      become_user: "{{env}}adm"
      set_fact:
         node_number: 1

    - name: Nommage des nodes
      become: yes
      become_method: sudo
      become_user: "{{env}}adm"
      community.general.xml:
        path: /data/{{env}}/web/tomcat/conf/server.xml
        xpath: /Server/Service/Engine
        attribute: jvmroute
        value: "node0{{node_number}}"
        backup: true
      when: load_balancing == "yes"

    - name: increment number node
      become: yes
      become_method: sudo
      become_user: "{{env}}adm"
      set_fact:
         node_number={{ node_number | int + 1 }}`

and calling this task like this

`- name: set count
  set_fact:
    node_number: 1

- name: Nommages des nodes tomcat
  include_tasks: nommage_nodes.yml
  with_items: "{{hostlb}}"
  when: not resultchrono.stat.exists`

What i want is on server1 define node01, then server2 define node02 etc..

Can you please help me ?

Answer 1

Q: "On server1 define node01, then server2 define node02 etc."

A: For example, given the inventory

shell> cat hosts
test_01
test_02
test_03

Get indexes and create the names of the variables

    my_index: "{{ ansible_play_hosts_all.index(inventory_hostname) + 1 }}"
    my_node_var: my_node_{{ my_index }}

gives (abridged)

ok: [test_01] =>
  my_node_var: my_node_1
ok: [test_02] => 
  my_node_var: my_node_2
ok: [test_03] => 
  my_node_var: my_node_3

Set the values

    - set_fact:
        my_node_{{ my_index }}: 1

gives (abridged)

ok: [test_01] => 
  lookup('vars', my_node_var): '1'
ok: [test_02] => 
  lookup('vars', my_node_var): '1'
ok: [test_03] => 
  lookup('vars', my_node_var): '1'

Increment the variable if you want to

    - set_fact:
        my_node_{{ my_index }}: "{{ lookup('vars', my_node_var) + 1 }}"

gives (abridged)

ok: [test_01] => 
  lookup('vars', my_node_var): '1'
ok: [test_02] => 
  lookup('vars', my_node_var): '1'
ok: [test_03] => 
  lookup('vars', my_node_var): '1'

Reference the variable

    - debug:
        var: my_node_1
      when: inventory_hostname == 'test_01'

gives (abridged)

ok: [test_01] => 
  my_node_1: '2'
skipping: [test_02]
skipping: [test_03]

, or use hostvars to reference any of the variables

    - debug:
        msg: |
          my_node_1: "{{ hostvars.test_01.my_node_1 }}"
          my_node_2: "{{ hostvars.test_02.my_node_2 }}"
          my_node_3: "{{ hostvars.test_03.my_node_3 }}"
      run_once: true

gives

  msg: |-
    my_node_1: "2"
    my_node_2: "2"
    my_node_3: "2"

---

Example of a complete playbook for testing

- hosts: all

  vars:

    my_index: "{{ ansible_play_hosts_all.index(inventory_hostname) + 1 }}"
    my_node_var: my_node_{{ my_index }}
    
  tasks:

    - debug:
        var: my_index
    - debug:
        var: my_node_var

    - set_fact:
        my_node_{{ my_index }}: 1
    - debug:
        var: lookup('vars', my_node_var)

    - set_fact:
        my_node_{{ my_index }}: "{{ lookup('vars', my_node_var) + 1 }}"
    - debug:
        var: lookup('vars', my_node_var)

    - debug:
        var: my_node_1
      when: inventory_hostname == 'test_01'

    - debug:
        msg: |
          my_node_1: "{{ hostvars.test_01.my_node_1 }}"
          my_node_2: "{{ hostvars.test_02.my_node_2 }}"
          my_node_3: "{{ hostvars.test_03.my_node_3 }}"
      run_once: true