I am installing
RUN apt-get install -y mailutils
Please select the mail server configuration type that best meets your needs.
Should be chosen to leave the current configuration unchanged.
Mail is sent and received directly using SMTP.
Internet with smarthost:
Mail is received directly using SMTP or by running a utility such
as fetchmail. Outgoing mail is sent using a smarthost.
All mail is sent to another machine, called a 'smarthost', for delivery.
The only delivered mail is the mail for local users. There is no network.
1. No configuration 3. Internet with smarthost 5. Local only
2. Internet Site 4. Satellite system
Use the following
FROM ubuntu:latest ENV DEBIAN_FRONTEND="noninteractive" RUN apt-get update && apt-get install -y mailutils
The important part is setting