IPv6 Network - Address Lifetime After successfully maneuvering past the DAD hurdle, addresses configured through stateless address autoconfiguration can be used until the “preferred lifetime” from the router advertisement message expires. In most cases, this won’t happen because new RAs refresh the timers. But if there are no more RAs, eventually, the preferred lifetime will elapse and the address becomes “deprecated.” New sessions shouldn’t use deprecated addresses but prefer “preferred” (non-deprecated) addresses, if available. However, existing sessions will continue to use the deprecated address. Eventually, the “valid lifetime” will also run out, and the deprecated address is removed from the interface. This will break any sessions that are still using the address.
