What's the "best" way to add an ip route using ansible? - ansible

Question

I am unable to find an ansible module that adds ip routes.
Basically the command I'm looking for should allow something like:
sudo ip route add 12.3.4.0/24 via 123.456.78.90
I found net_static_route_module which seems related, but is deprecated since 2022-06-01.
A simple solution would be:
- name: Add a route
ansible.builtin.shell:
cmd: sudo ip route add 12.3.4.0/24 via 123.456.78.90
of course, but inbuilt modules are usually better.
Additional information
This task will be executed on a subset of all nodes (ubuntu 22.04 machines that are all part of a cloud cluster using openstack) (specified by groups). Concrete subnets and IPs will be defined using variables.
An example hostfile could look like this:
master:
hosts:
localhost:
ansible_connection: local
ansible_python_interpreter: /usr/bin/python3
ansible_user: ubuntu
ip: localhost
workers:
children:
ephemeral:
hosts: {}
hosts:
someworker:
ansible_connection: ssh
ansible_python_interpreter: /usr/bin/python3
ansible_user: ubuntu
This playbook will be used to setup wireguard. Every vpn-node (those nodes will be connected with each other via wireguard) is connected in its own subnet with multiple worker nodes. Those workers need to add the ip route to get back to the master node which is in a different subnet, but in the same virtual subnet created by wireguard and the vpn nodes). I do not think that this is related to my question, but I might overlook how this can affect the right answer.

Answer 1

From your description I understand that you like to configure the network route settings on a Linux based operating system (Debian/GNU Linux, Ubuntu 22.04) and not on a dedicated router or switch.
Whereby the mentioned module net_static_route was for providing
... declarative management of static IP routes on network appliances (routers, switches et. al.).
and became deprecated
Removed in: major release after 2022-06-01
Why: Updated modules released with more functionality
Alternative: Use platform-specific [netos]_static_route module
it further recommends to use the vendor and platform specific modules instead.
Certain Linux Distributions tend to integrate and use NetworkManager for creating and managing network connections.
Documentation
RHEL7 - Getting Started with NetworkManager
ArchLinux - NetworkManager
Ubuntu - NetworkManager
...
So the respective Ansible module for this is nmcli module – Manage Networking. You may have a look into the Parameters and Examples, especially into the parameters for route*.
Further Readings
For more examples have a look at
How to configure network settings with Ansible system roles
Linux System Roles