Overview

ListManager requires that some ports are accessible through the firewall for correct operation.

Failing to reach those ports may cause issues when delivering and receiving mailings, as well as managing the system and accessing its web interface.

Information

The following ports need to be open on your firewall:

• 25 - TCP for SMTP (receiving mail; inbound)
• 53 - UDP for DNS lookups (outbound)
• 80 - Web interface
• 119 - TCP for NNTP (reading newsgroups; inbound)
• 2021 - TCP for Tclport (If the web interface is on a different IP)

About DNS lookups

ListManager initiates the transaction from a random source port (1024-65536) to port 53 on remote name servers, and the UDP DNS response packet returns to that random source port. Most firewalls handle this without any issue, but for some it may be necessary to allow inbound UDP traffic to ports 1024-65535.

About Tclport

If the web server is running on a different machine outside the firewall, or running scripts against ListManager from a machine outside the firewall, you will also need to have port 2021 open so that the web interface can communicate to the back-end ListManager service.