Thanks. We have a firewall that can handle DoS attacks.
Have done some testing now, with port 2222 open to public internet. ERA is now setup with an DNS-name that is available for lookup on both inside network and outside public internet, linked to port 2222.
Virus signature updates works fine from both inside local network and from outside public internet now.
But when I tried to add a client task in ERA to do a software install (update ESET Endpoint Security to latest version), it fails.
It works fine inside local network, but not from public internet.
Does the software install function require access to port 3128 aswell?