Variable prefix

Prefix variable names with role or project prefix.

Prefix variables in Ansible roles / collections with the role name. For example harbor_hostname. Prefix other / project variables with a project prefix for example c2_cacerts2_ca_dir.


Without a project of role prefix it is not always clear where variables are used. Without a prefix there is also a chance of conflicting duplicating variables.


In a typical project typically all kinds of variables are created / used. Some variables are used in Ansible roles but some do not. This can be confusing and lead to mistakes / problems.


  1. Prefix all variables used in an Ansible role with the role name for example harbor_.
  2. Prefix all other / project variables - that only exists in group_vars or host_vars folder - with a project prefix for example c2_.

Examples and implementation

  1. For example harbor_hostname for the hostname of the Harbor instance. The prefix is harbor_ because this is a variable that is part of the c2platform.mgmt.harbor Ansible role.
  2. In C2 Inventory project c2platform/ansible c2_ is used as a prefix see for example c2_cacerts2_ca_dir in group_vars/all/smallca.yml.
  3. In the RWS Inventory project c2platform/rws/ansible-gis gs_ is used as prefix. See Configuring a Web Proxy Server Example for MS Windows Hosts for an example on how gs_proxy_regedit is utilized to configure a web proxy.