Ansible loop variable

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1

Hello friends,

Am having a challenge finding a solution to below issue.
I need to generate multiple network files based on single template and the value of template should change based on the item like IP/NM/GW .

Example

vars:
  docker1ip: 1.2.3.4
  docker1nm: 255.255.255.1
  docker1gw: 1.2.3.1
  docker2ip: 1.2.3.5
  docker2nm: 255.255.255.2
  docker2gw: 1.2.3.1
  • name: Generating docker network Files
    template: src=templates/docker_interface dest=/etc/sysconfig/network-scripts/ifcfg-docker{{ item }}

vars:
ipaddress: {{ docker{{ item }}ip }}
netmask: {{ docker{{ item }}nm }}
gateway: {{ docker{{ item }}gw }}
with_sequence: start=1 end=2 stride=1

template

DEVICE=docker{{ item }}
BONDING_OPTS=“miimon=100 mode=1”
ONPARENT=yes
BOOTPROTO=static
IPADDR={{ ipaddress }}
NETMASK={{ netmask }}
GATEWAY={{ gateway }}

Above task doesnt work but I need a solution it may be a different approach too.

2

Am having a challenge finding a solution to below issue.
I need to generate multiple network files based on single template and the
value of template should change based on the item like IP/NM/GW .

Example

vars:
  docker1ip: 1.2.3.4
  docker1nm: 255.255.255.1
  docker1gw: 1.2.3.1
  docker2ip: 1.2.3.5
  docker2nm: 255.255.255.2
  docker2gw: 1.2.3.1

  - name: Generating docker network Files
    template: src=templates/docker_interface
dest=/etc/sysconfig/network-scripts/ifcfg-docker{{ item }}
    vars:
      ipaddress: {{ docker{{ item }}ip }}
      netmask: {{ docker{{ item }}nm }}
      gateway: {{ docker{{ item }}gw }}
    with_sequence: start=1 end=2 stride=1

Variables in variables is not possible like this, you need to do it like this
https://docs.ansible.com/ansible/faq.html#when-should-i-use-also-how-to-interpolate-variables-or-dynamic-variable-names

template

DEVICE=docker{{ item }}
BONDING_OPTS="miimon=100 mode=1"
ONPARENT=yes
BOOTPROTO=static
IPADDR={{ ipaddress }}
NETMASK={{ netmask }}
GATEWAY={{ gateway }}

Above task doesnt work but I need a solution it may be a different approach
too.

Since you are specifying everything why not restructure the variable, one example on how to do it:

vars:
   docker_inv:
     - host: docker1
       ip: 1.2.3.4
       nm: 255.255.255.1
       gw: 1.2.3.1
     - host: docker2
       ip: 1.2.3.5
       nm: 255.255.255.2
       gw: 1.2.3.1

   - name: Generating docker network Files
     template: src=templates/docker_interface dest=/etc/sysconfig/network-scripts/ifcfg-{{ item.host }}
     with_items: '{{ docker_inv }}'

template

3

HI Kai Stian Olstad ,

That helped me and thanks a ton but that scenario works better if we know the number of docker networks.
Here is the exact use case where I need to generate multiple docker network files based on the number of container count and push a single template multiple times to match the container count updating the correct network details. I would get docker1ip/nm/gw docker2ip/nm/gw dockernip/nm/gw from external source and just for testing i mentioned them as vars in this playbook.