Describes the Duplicate Address Detection process used by Neighbor Discovery to identify address conflicts within a network. This feature ensures proper IPv6 address management on ACI fabric leaf layer 3 interfaces while allowing for specific configuration overrides to support border leaf redundancy.
Duplicate Address Detection (DAD) is a process used by Neighbor Discovery to detect duplicated addresses in the network.
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Enabled by default for link-local and global-subnet IPv6 addresses on ACI fabric leaf layer 3 interfaces.
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Configurable via REST API or GUI to disable the process for specific IPv6 global-subnets.
DAD Configuration and Redundancy
Configure the ipv6Dad="disabled" setting when the same shared secondary address is required across L3Outs on different border leaf switches to provide redundancy. Disabling the DAD process prevents the system from incorrectly identifying shared secondary addresses on multiple border leaf switches as duplicates, which would otherwise cause the address to enter a DUPLICATE DAD state and become unusable.