IP & Firewall Settings

Firewall Information


DirectMX connects directly to your mail server for a variety of reasons. You may need to configure your firewall so that DirectMX has access to do so. Here are a list of IP Addresses and port numbers that DirectMX uses.

Inbound and Outbound Filtering

All DirectMX services should be configured as two-way, meaning that we can contact you from these IP addresses and ports, and your server should be able to contact us on these IP addresses and ports. This facilitates both the inbound receipt and delivery of email, as well as your outbound or smarthosting configuration.

IP Addresses


All DirectMX services reside on the following IP ranges:

IPv4 - 64.111.17.16/27
IPv6 - 2607:2800:102:203::/64

Port Numbers


DirectMX will only ever connect to your equipment using TCP.
PortRequired?Role
25 Required SMTP Mail delivery & recipient verification
587 optional Secure SMTP Mail delivery
389 optional LDAP recipient verification & authentication
636 optional Secure LDAP recipient verification & authentication
143 optional IMAP-based recipient verification & authentication
110 optional POP-based recipient verification & authentication
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