Recent community reports around Ansible network automation stem from a regression introduced in ansible-core 2.19 related to how network *_config modules handle templating of the src parameter. Historically, some network modules supported inline Jinja2 templating directly within src (for example, src: template.j2). In ansible-core 2.19, Ansible language enhancements changed some underlying behaviors used during network configuration generation. Several network collections depended on the previous behavior, which led to breakage when those assumptions changed.
- name: Apply configuration from template
arista.eos.eos_config:
src: template.j2
Ansible engineering has put out a fix, if you are running ansible-core 2.19 you can just upgrade ansible.netcommon
ansible-galaxy collection install ansible.netcommon --upgrade
There is more info on this knowledge base article: Ansible Network Automation - Issue Rendering Jinja2 Template - Invalid input - Red Hat Customer Portal