Whether to accept DAD (Duplicate Address Detection). 0: Disable DAD 1: Enable DAD (default) 2: Enable DAD, and disable IPv6 operation if MAC-based duplicate link-local address has been found.
DAD operation and mode on a given interface will be selected according to the maximum value of conf/{all,interface}/accept_dad.
Nb: per interface setting (where “interface” is the name of your network interface); “all” is a special interface: changes the settings for all interfaces.
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