Docker 17.06 introduces swarm service configs, which allow you to store non-sensitive information, such as configuration files, outside a service’s image or running containers. This allows you to keep your images as generic as possible, without the need to bind-mount configuration files into the containers or use environment variables.
To add configs to Portainer click Configs and then Add config.
Then, in the Editor, you need to write your configuration. In this example, you can see an nginx configuration file.
Once this config is defined, you can add labels and/or manage access control of this config.
When everything is set, click Create config.