How to set SMTP Server Container

For sending e-mails 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 e-mails 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