[FS#426] odhcpd: consider sending some low-interval multicast RA

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Eric Luehrsen (EricLuehrsen) 

Attached to Project - LEDE Project
Summary - odhcpd: consider sending some low-interval multicast RA
Task Type - Feature Request
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Low
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - I might be wrong, but it appears odhcpd only sends unicast RA when RA SOLICIT is sent. This seems like a sane behavior assuming high WiFi client base (OpenWrt/LEDE). Especially when a radio restarts, the in-rush flow of multicast could be crippling. However it might be useful for general connection maintenance for odhcpd to send an unsolicited multicast RA every 5 minutes. It might also be useful to send a multicast RA on RA SOLICIT if such has not occurred for 1 minute. In all other cases, default to the unicast behavior.
 

More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=426