continuing to read RFC 6762 at section 8.4
(
https://datatracker.ietf.org/doc/html/rfc6762#section-8.4) I find:
At any time, if the rdata of any of a host's Multicast DNS records
changes, the host MUST repeat the Announcing step described above to
update neighboring caches. For example, if any of a host's IP
addresses change, it MUST re-announce those address records.
This is exactly the case I was describing.
I have tested both the 2.1.3 release of lwip and the current master. In
both cases mDNS doesn't re-announce.
I believe this can be considered a bug.
best regards
Max
Massimiliano Cialdi
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On 14/03/22 11:02, massimiliano cialdi wrote:
>
> hello,
>
> In RFC 6762 I find (section 8):
>
>
> "Whenever a Multicast DNS responder starts up, wakes up from sleep,
> receives an indication of a network interface "Link Change" event, or
> has any other reason to believe that its network connectivity may
> have changed in some relevant way, it MUST perform the two startup
> steps below: Probing (Section 8.1) and Announcing (Section 8.3)."
>
>
> Does the IP change fall under one of the reasons for reannouncement?
> In my opinion it should but I'm not sure. I mean, if I set
> LWIP_DHCP_AUTOIP_COOP and assigned a link-local address, and then a
> dhcp server is turned on, my IP address changes. I believe that this
> should require sending a new announcement to inform of the newly
> acquired IP.
>
> Lwip doesn't seem to act like that, but I don't know if it should.
> What do you guys think?
>
>
> best regards
>
> Max
>
