Bug #413

dhcpv6 fails to acquire a /60 correctly on a cablemodem

Added by David Taht on Oct 26, 2012. Updated on Apr 11, 2013.
Closed High Dave Täht


In testing with a real cablemodem, with a /60 provisioned, only the first was picked up in cerowrt’s default configuration.

Furthermore, the wide-dhcp script would assign all the interfaces the same /64 network (modified by the eui-64)

The attached dhcpv6 capture file shows a trace of the attempted transaction.


  • dhcpv6.cap (application/vnd.tcpdump.pcap; 30.8 kiB) David Taht Oct 26, 2012


Updated by John Jason Brzozowski on Nov 5, 2012.
The traces indicate that the ADVERTISE offers a /64 IAPD. I suggest updating the SOLICIT to include “::/60” for the IAPD per RFC3633 to hint that a shorter prefix is desired.
Updated by Dave Täht on Dec 3, 2012.
there is a new tiny dhcp6-pd daemon under development that I will try next. continuing with the dead wide, and the huge dibbler and isc-dhcp is not worth it.
Updated by David Taht on Apr 11, 2013.
The new dhcp-pd daemon in cerowrt 3.7.5 and later works correctly in nearly all cases

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