Folks, We have been discussing the potential problems associated with SLAAC renumbering events for a while now -- one of the most common cases being ISPs rotating home prefixes, and your devices ending up with stale/invalid addresses. We have done quite a bit of work already: * Problem statement: https://datatracker.ietf.org/doc/html/rfc8978 * CPE recommendations: https://datatracker.ietf.org/doc/html/rfc9096 But there's still some work to do to address this issue: The last remaining it is to improve SLAAC such that hosts can more gracefully deal with this renumbering events. In that light, IETF's 6man has been working on this document: https://www.ietf.org/archive/id/draft-ietf-6man-slaac-renum-04.txt And we have proposed a simple algorithm for SLAAC (an extension, if you wish) that can easily help, as follows: If you (host) receive an RA that contains options, but not all of the previously-received options/information, simply send a unicast RS to the local-router, to verify/refresh that such missing information is still valid. If the information is stale, get rid of it. I presented this algorithm at the last IETF meeting (https://youtu.be/eKEizC8xhhM?t=1308). (You may find the slides here: https://datatracker.ietf.org/meeting/114/materials/slides-114-6man-improving...) Finally, I've sent draft text for the specification of the algorithm here: https://mailarchive.ietf.org/arch/msg/ipv6/KD_Vpqg0NmkVXOQntVTOMlWHWwA/ We would be super thankful if you could take a look at the draft text (i.e., https://mailarchive.ietf.org/arch/msg/ipv6/KD_Vpqg0NmkVXOQntVTOMlWHWwA/) and provide feedback/comments. If you can post/comment on the 6man wg mailing list (https://www.ietf.org/mailman/listinfo/ipv6), that´d be fabulous. But we'll appreciate your feedback off-line, on this list, etc. (that'd still be great ;-) ) Thanks in advance! Regards, -- Fernando Gont SI6 Networks e-mail: fgont@si6networks.com PGP Fingerprint: F242 FF0E A804 AF81 EB10 2F07 7CA1 321D 663B B494