Introduction:

PaperCut Mobility Print, like Apple’s Bonjour, relies on mDNS protocol to advertise services on the local network. While mDNS is generally easy to troubleshoot, it can fail when clients and the server are in different subnets. In this guide, we will explore methods to troubleshoot printer discovery problems in an mDNS environment.

Checking Subnet Compatibility:

Before diving into troubleshooting, ensure that both the client and Mobility Print server are in the same subnet. Follow these steps:

1. On the Mobility Print server, open a command prompt or terminal window.
2. Run “ipconfig” on Windows or “ifconfig” on macOS or Linux.
3. Note down the IPv4 Address and Subnet Mask.
4. Use a subnet calculator to determine the IP address range in the subnet.
5. Verify that the client’s IP address falls within this range.

Verifying Client and Mobility Print Server:

To check the client’s IP address on different devices:

• Windows: Open a command prompt window and type “IPconfig.”
• macOS: Navigate to System Preferences > Network > select the network adapter.
• iOS: Navigate to Settings > WiFi > select the WiFi network.
• Chrome: Navigate to Network and Settings > WiFi > click the ⓘ button.
• Android: Go to Settings > Wireless > WiFi.

  

Solving Different Subnet Issues:

If clients and the Mobility Print server are in different subnets, consider these solutions:

1. Connecting Mobility Print Server to Multiple Networks:

If you have wired and WiFi networks, connect the Mobility Print server to both networks. Add an additional network interface (e.g., a WiFi dongle) to the server. The Mobility Print server will automatically broadcast printers on both interfaces, enabling clients on both subnets to discover the printers.

2. Enabling Bonjour Forwarding on the Router:

If your networking hardware supports Bonjour Forwarding, configure the router or wireless access points to forward mDNS traffic from the Mobility Server VLAN to the user VLANs. Whitelist specific Bonjour services for forwarding across subnet barriers. Consult your network administrator or IT service provider for assistance.

Verifying Printer Publication with mDNS Tools:

For macOS users, verify printer publication using mDNS tools:

• Run the command “dns-sd -B _ipps._tcp” on a macOS laptop connected to Wi-Fi.
• This command will display a list of printers published by Mobility Print.
• Non-macOS users can use Bonjour browsers to see visible Bonjour services under the namespace “_ipps._tcp.”

Ensuring mDNS Broadcast is Enabled:

Double-check that mDNS broadcast is enabled in Mobility Print:

• This setting is enabled during Mobility Print installation but may be disabled during DNS record configuration.
• In the Mobility Print Admin interface, click Discovery options.
• Click Turn on mDNS.

Conclusion:

Troubleshooting printer discovery issues in an mDNS environment can be a simple process when following these steps. Ensuring clients and the Mobility Print server are in the same subnet, verifying printer publication, and enabling mDNS broadcast are essential for seamless printer discovery. If issues persist, consider connecting the Mobility Print server to multiple networks or enabling Bonjour Forwarding on the router. With these solutions, you can optimize printer services within your mDNS network.