Firewall Portlist

For a smooth operation of the REDDOXX Appliance, some ports must be opened at the firewalls used.

  • SMTP/25 TCP in/out
    For incoming / outgoing emails

  • POP3(s)/110 (995) TCP in
    To fetch mail via POP3(s)

  • DNS/53 UDP/TCP out
    For domain name service requests to your DNS server.

  • HTTP(s)/80, (443) TCP out
    For communication with the REDDCRYPT Portal (
    In case of technical problems, the REDDOXX support employee can connect to the appliance if the service has been started by the administrator.
    For software updates (, as well as spam and CISS validations (
    For registration and licence verification and portal communication (updates) of the appliance, is required.
    For the display and transmission of optional telemetry data, and are required.
    Access to is required to retrieve virus scanner updates.

  • HTTP(s)/80,443 TCP in
    To allow communiction with the REDDOXX webinterface from Remote (e.g. for adminstrative purpose,
    or to Access the User Webinterface or to connect with the REDDOXX Mobile APP).
    To use Lets Encrypt SSL Certificates

  • NTP/123 UDP out
    To adjust Time with a Time Server

  • SMB 137,138 UDP out, 139 TCP out, CIFS 445 TCP out, iSCSI 3260 TCP out
    For backup and archiving (mail depot) on a remote share.

  • LDAP/389 TCP out, LDAP/636 out für SSL
    For user authentication and recipient check via Active Directory, OpenLDAP, Novell eDircetory, Lotus Notes Domino.
    To fetch S/MIME Certificates from external LDAP Directorys in MailSealer

  • LDAP/3268 TCP out
    For higher-performance LDAP queries against a Global Catalog Server.

  • REDDOXX/55555 TCP out
    For communication with the fuzzy filter remote service for spam detection.

You should pay attention to these ports when the REDDOXX Appliance is included in another network segment,
e.g. a DMZ, and separated from the internal LAN through a firewall.
The Remote Support communicates outgoing via Port 80.
As Protocol, the remote Support uses no HTTP but SSH (so your Firewall should not check if the port matches the protocoll).
It is not recommended to separate the appliance with a switch or firewall from a connected storage, as outages could damage the archive container.