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Configure IP addresses to consolidate DNS servers for migration purposes. For information, see Configuring IP Addresses.
Add anycast addresses to improve the reliability and performance of DNS services in multiple locations. For information, see About Anycast Addressing for DNS.
Separate DNS traffic by assigning an IP address as the source port for DNS queries. For information, see Specifying Source Ports.
When you use the loopback interface for anycast addressing, the upstream and neighboring routers can continue to advertise anycast addresses without being affected by hardware malfunctions. To configure non-anycast addresses on the loopback interface, complete the following:
Add IP addresses to the loopback interface. For information, see Configuring IP Addresses.
Enable DNS services on the loopback addresses. For information, see Specifying Port Settings for DNS and its subtopic, Specifying Source Ports.
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Add an IP address of the source port for DNS queries. For information, see Configuring IP Addresses.
Select the source IP for DNS queries. For information, see Specifying Source Ports.
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