Configure a server behind a firewall or NAT

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In some situations, the Mobility Print internal IP address might not be reachable by the requesting devices. For example, this happens if the Mobility Print server is behind a firewall.

Mobility Print allows you to configure a specific IP address that clients can use to reach the Mobility Print server.

Firewalls are used to restrict and control the flow of traffic on a network.

To allow end users to communicate with the DNS and Mobility Print servers, you need to make sure the ports are available.


Mobility Print helps to solve the issue of network clients' IP addresses being obscured by Network Address Translation (NAT).

NATs obscure the back-end addresses for either clients or servers. Traditionally, many rules might have been needed to be applied to a NAT to allow traffic to route between different devices on either side of a NAT. Mobility Print minimizes some of these rules and issues by specifying an IP address for the Mobility Print server to use.

Configure the Accessible IP address of the Mobility Print server

For complex networks that use NATs, or when a Mobility Print server has multiple network interfaces, we recommend setting the Accessible IP address. This is what the Mobility Print server will share with clients when queried over DNS or mDNS, so that clients know where to send a print job.

  1. On the Mobility Print server, open the following file in a text editor:


  2. Locate the line starting with AccessibleIP = "". By default it has an empty value.

  3. Type the IP Address for clients to use to access the Mobility Print server. For example:

    AccessibleIP = ""

  4. Restart the PaperCut Mobility Print service.