DDM: Troubleshooting DNS Service Discovery (DNS-SD)

• Verify host record is correct and DDM Server can reach the DNS Server by accessing DDM via a web browser using its FQDN
  • The Network Diagnostics tool tells you if DDM can ping the DNS server. This can report a FAIL if the server has ICMP requests turned off (Windows Server does by default). This also will not tell you if the host record is set up correctly.
• Verify SRV records have been set up and are correct i.e. are using the domain(s) devices/controllers are getting via DHCP, DDM server FQDN is correct, ports/services are correct.
  • The Network Diagnostics tool can help to verify this.
  • If the domain search path set in the DHCP server has multiple entries be sure the first entry is used in the SRV/TXT records as devices only use the first entry.
  • If devices are in a different DNS Domain than the DDM server this will report a FAIL in the Network Diagnostics tool but does not mean they are set up incorrectly.
• Verify the undiscovered device(s) Dante firmware is version 4.0+.
  • If the undiscovered device(s) Dante firmware version is pre 4.0 (and 4.0+ firmware is not available from the manufacturer), you’ll need to associate the device with a domain using manual enrollment by IP address.
  • Allow association with pre 4.0 firmware devices must be enabled the DDM’s Network & Security Settings and on a per domain basis prior to enrolling legacy (pre 4.0 Dante firmware) devices into a domain.
  • Since legacy devices are manually associated with domains via their IP address, changes to their IP address will break the association, and they must be associated again.
• If everything appears to be set up correctly, you’ll need to get a packet capture of DNS traffic on the network. Note: Because this is unicast traffic between a device and the DNS server port mirroring is required.
  • Devices send queries and the DNS server responds with the SRV record and DDM Server’s IP Address.
  • There is a known issue where some devices are sending the proper DNS query and then sending a corrupted query that the DNS server responds with “No such name” thus making the device undiscoverable. Current work around is to enroll devices exhibiting this behavior manually via IP.
  • If a device is not sending queries, Domain Credentials need to be cleared in Dante Controller.