turning on comcast v6

Fri Dec 20 05:42:46 UTC 2013

On Fri, Dec 20, 2013 at 12:30 AM, Owen DeLong <owen at delong.com> wrote:
>>
>> FYI - DHCP-PD is now working better in RouterOS 6.5
>>
>> Prefix length hints are now available (CLI) only.
>>
>> /ipv6 dhcp-client add add-default-route=yes interface=<wan interface>
>> pool-name=dhcp-pd \
>> prefix-hint=::/60
>>
>
> I'd like to encourage people to use prefix-hint=::/48.
>
> The router should accept the /60 and deal with it, but it's better to have Comcast's logs show that you requested a proper full-size prefix.
>
> I'm almost afraid to ask about the phrase "add-default-route=yes" in the dhcp-client configuration. That seems wrong on the face of it since you should be getting your routing information from RA and not DHCP.

I think if I ask (via wide-dhcpv6-server) for more than is going to be
sent I don't get anything configured at all :(

I'm pretty sure I get sent a /64 in the response packet, but I don't
install that.. which leads to busted v6 configuration on my device.

>
>> In the case of Comcast (and anecdotally ISC DHCP) - You'll either need
>> to wait out the the lease time (4 days) or ask Comcast to nicely clear
>> out your /64 lease manually.  Release/renew doesn't release your current
>> DHCP lease.  I was getting A /64 and /60 (/64 had a preference of 255)
>> before Comcast removed the /64 lease manually.
>
> Is it somehow harmful to have both?
>
> Owen
>
>