Alcatel Carrier Internetworking Solutions 6800 User Manual

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Troubleshooting DNS
DNS Configuration Considerations
OmniSwitch Troubleshooting Guide
September 2005
page 6-3
• If you find conflicting information, then see which portion has the wrong information and focus on that 
layer again (layer 2, 3, or 7).
• The response packet should contain the following fields: DLC with the source Mac address of the DNS 
server, and the destination MAC address of the switch. The IP header will contain the source IP 
address of the DNS server, and the destination IP address of the switch. The UDP header will contain 
the source port 53 (the destination port varies). The DNS header will contain a response flag, and the 
answer section will contain the name and the IP address that the name references.
DNS Configuration Considerations
CLI has a limitation when entering the domain name to 126 characters. If you enter the name from 
WebView you can enter up to 255 characters, and it will show up properly from the CLI. There is a limit 
of up to a maximum of 3 DNS servers.