Whether to perform Optimistic Duplicate Address Detection (RFC 4429). 0: disabled (default) 1: enabled
Optimistic Duplicate Address Detection for the interface will be enabled if at least one of conf/{all,interface}/optimistic_dad is set to 1, it will be disabled otherwise.
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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