480073 FSB Multiple Source DNS Issue

Summary

This bulletin outlines a DNS-handling issue affecting T10 units running APU software version 5.3.5.6. While the APU102 application correctly pushes DNS settings to the network adapter during network configuration, the Windows operating system may have already assigned DNS servers to the adapter.  This results in DNS entries from both the DNS.DAT file on the APU and DNS servers appropriate for the open internet.

Impact

This will present to the user as the APU being unable to resolve URLs.

Affected Products

This issue affects APUs with T10 processors running application software version 5.3.5.6.

Diagnosis

Symptoms:

• Failed hostname lookups
• Failed server authentication
• Reporting/sync delays
• Loss of connectivity in DNS-required networks

Confirmation:

• At the APU Change prompt issue the following command

SHELL IPCONFIG/ALL

• The response should look like:

• Notice that the DNS Servers include 8.8.8.8 and 8.8.4.4.  These were not in the DNS.DAT.
• The IPCONFIG utility shows the DNS errors.

Mitigation

The DNS servers can be updated manually.

Remove DNS Servers

All DNS servers that are not desired must be removed.

• At the APU Change prompt issue the following command
• shell netsh interface ipv4 delete dnsservers "Ethernet" "dns-server-to-delete"

shell netsh interface ipv4 delete dnsservers "Ethernet" 8.8.8.8

Add DNS Servers

All DNS servers that are not desired must be removed.

• At the APU Change prompt issue the following command
• shell netsh interface ipv4 add dnsservers "Ethernet" "dns-server-to-add"

shell netsh interface ipv4 add dnsservers Ethernet 8.8.8.8

Verification

• Roboot the APU
• Upon reboot, check the network settings
• If the network settings are not maintained, contact Comet Support

Resolution

Check future software release notes for improvements in DNS handling.