Re: [PATCH net-next 0/4] bridge: implement Multicast Router Discovery (RFC4286)

From: Nikolay Aleksandrov
Date: Fri Dec 21 2018 - 10:37:49 EST


On 12/21/18 5:15 PM, Linus LÃssing wrote:
> Hi,
>
> This patchset adds initial Multicast Router Discovery support to
> the Linux bridge (RFC4286). With MRD it is possible to detect multicast
> routers and mark bridge ports and forward multicast packets to such routers
> accordingly.
>
> So far, multicast routers are detected via IGMP/MLD queries and PIM
> messages in the Linux bridge. As there is only one active, selected
> querier at a time RFC4541 ("Considerations for Internet Group Management
> Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping
> Switches") section 2.1.1.a) recommends snooping Multicast Router
> Advertisements as provided by MRD (RFC4286).
>
>
> The first two patches are refactoring some existing code which is reused
> for parsing the Multicast Router Advertisements later in the fourth
> patch. The third patch lets the bridge join the all-snoopers multicast
> address to be able to reliably receive the Multicast Router
> Advertisements.
>
>
> What is not implemented yet from RFC4286 yet:
>
> * Sending Multicast Router Solicitations:
> -> RFC4286: "[...] may be sent when [...] an interface is
> (re-)initialized [or] MRD is enabled"
> * Snooping Multicast Router Terminations:
> -> currently this only relies on our own timeouts
> * Adjusting timeouts with the values provided in the announcements
>
>
> Regards, Linus
>
>
>

Hi Linus,
Nice work, unfortunately net-next is currenty closed. Anyway I'll
review the patches in detail after the holidays so if there's
anything it can be adjusted for when net-next opens up.

Thanks,
Nik