turning on comcast v6

Owen DeLong owen at delong.com
Fri Dec 20 05:30:35 UTC 2013

> 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.

> 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?


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