Provisioning Kaktus

As detailed in network topology, we’ll have 3 Kaktus instances:

• kaktus-eu-west-a-1:
  • with VLAN 101 as administrative segment with 10.50.101.11,
  • with VLAN 102 as storage segment with 10.50.102.11,
  • with VLAN 201 to 209 as service VLANs.
• kaktus-eu-west-a-2:
  • with VLAN 101 as administrative segment with 10.50.101.12,
  • with VLAN 102 as storage segment with 10.50.102.12,
  • with VLAN 201 to 209 as service VLANs.
• kaktus-eu-west-a-3:
  • with VLAN 101 as administrative segment with 10.50.101.13,
  • with VLAN 102 as storage segment with 10.50.102.13,
  • with VLAN 201 to 209 as service VLANs.

Inventory Management

It is now time to declare your Kaktus instances in Ansible’s inventory. Simply extend the ansible/inventories/hosts.txt the following way:

[kaktus]
10.50.101.11 name=kaktus-eu-west-a-1 ansible_ssh_user=ubuntu
10.50.101.12 name=kaktus-eu-west-a-2 ansible_ssh_user=ubuntu
10.50.101.13 name=kaktus-eu-west-a-3 ansible_ssh_user=ubuntu

The instances are now declared to be part of kaktus group and Ansible will use ubuntu local user account to connect through SSH.

Note that doing so, you can now safely:

• declare host-specific variables in ansible/host_vars/10.50.101.{11,12,13}.yml files.
• declare host-specific sensitive variables in ansible/host_vars/10.50.101.{11,12,13}.sops.yml file.
• declare kaktus group-specific variables in ansible/group_vars/kaktus/main.yml file.
• declare kaktus group-specific sensitive variables in ansible/group_vars/kaktus.sops.yml file.
• declare any other global variables in ansible/group_vars/all/main.yml file.
• declare any other global sensitive variables in ansible/group_vars/all.sops.yml file.

Note that Ansible variables precedence will apply:

role defaults < all vars < group vars < host vars < role vars

Network Configuration

We’ll instruct the Ansible collection to provision network settings through Netplan. Note that our example is pretty simple, with only a single network interface to be used for private LAN, no link aggregation being used (recommended for enterprise-grade setups).

Let’s declare the following configuration in ansible/inventories/host_vars/10.50.101.2.yml file:

kowabunga_netplan_config:
  ethernet:
    - name: "{{ lan_dev }}"
      mac: "aa:bb:cc:dd:ee:ff"
  vlan:
    # EU-WEST admin network
    - name: vlan101
      id: 101
      link: "{{ lan_dev }}"
      ips:
        - 10.50.101.11/24
      routes:
        - to: default
          via: 10.50.101.1
    # EU-WEST storage network
    - name: vlan102
      id: 102
      link: "{{ lan_dev }}"
      ips:
        - 10.50.102.11/24
    # EU-WEST services networks
    - name: vlan201
      id: 201
      link: "{{ lan_dev }}"
    [...]
    - name: vlan209
      id: 209
      link: "{{ lan_dev }}"

You’ll need to ensure that the MAC addresses and host and gateway IP addresses are correctly set, depending on your setup. Once done, you can do the same for the alternate Kaktus instances in ansible/inventories/host_vars/10.50.101.{12,13}.yml files.

Extend the ansible/inventories/group_vars/kaktus/main.yml file with the following to ensure generic settings are propagated to all Kaktus instances:

kowabunga_netplan_disable_cloud_init: true
kowabunga_netplan_apply_enabled: true