How to set SMTP Server Container

For sending emails from our application we use SMTP server container in separate Kubernetes pod so we need to set some additional settings as permission to be able to send emails from webserver-php-fpm pod.

For this purpose, we have set RELAY_NETWORKS ENV variable with all private networks that can be created by docker into /project-base/kubernetes/deployments/smtp-server.yml for pod of SMTP container (#777), for instance:

image: namshi/smtp:latest
env:
-   name: RELAY_NETWORKS
    value: :192.168.0.0/16:10.0.0.0/8:172.16.0.0/12