ipv6 default router Operation not permitted

[Joe Holden]

Strange, I used this setup on an OVH machine a while ago, seemed to work 
- perhaps something isn't properly configured at their end properly

Schrodinger wrote:
> On 2013/03/13 15:52, Joe Holden wrote:
>> Just use router solicitation to ask for the link-local gateway, that is 
>> the "correct" way to do it.
>>
> 
> Hi Joe,
> 
> If you read some of this thread you'll note that router advertisements
> are being disabled by the hosting provider. While their documentation
> indicates the use of router advertisments this does not solve the issue
> that I get "Operation not permitted" when trying to ping the default
> gateway.
> 
> Without ACCEPT_RTADV on re0 FreeBSD does not even perform NEIGHBOUR
> solicitation for 2001:41d0:2:e7ff:ff:ff:ff:ff - presumably because it
> thinks that this is not on the same link as re0.
> 
> C.
> 
>> Schrodinger wrote:
>>> Damien, 
>>>
>>> I appreciate your replies very much, but I'm a subscriber so just reply
>>> to the mailing list. Thanks.
>>>
>>> On 2013/03/13 14:19, Fleuriot Damien wrote:
>>>
>>> [SNARF]
>>>
>>>> These are indeed correct, thanks for clarifying.
>>>>
>>> I thought that's what I said in my first email ;) Sorry for any
>>> confusion.
>>>
>>>> Find below the config I'm using on an old OVH box.
>>>> Said config might be outdated now (as per OVH's guide on setting up IPv6 [1]) , however that was at the time the only way to get things working properly.
>>>>
>>>> rc.conf
>>>> ===
>>>> #Range IPv6: 2001:41D0:2:613b::/64
>>>> ipv6_enable="YES"
>>>> ipv6_ifconfig_re0="fe80::21c:c0ff:fef3:31fa/64 scopeid 0x1"
>>>> ipv6_ifconfig_re0_alias0="2001:41d0:2:613b::dead:beef/56"
>>>> ipv6_defaultrouter="2001:41d0:2:61ff:ff:ff:ff:ff"
>>>> ===
>>>>
>>> You have /56 and this is what I believe to be the incorrect way to get
>>> this to Just Work. I think this assume that anyone else in this /56 is
>>> in the same layer two segment as you.... 
>>>
>>>> routing table
>>>> ===
>>> [SNARF]
>>>> ===
>>>>
>>>>
>>>>
>>>> Notice that said config actually works:
>>>> ===
>>>> $ ping6 www.google.com
>>>> PING6(56=40+8+8 bytes) 2001:41d0:2:613b::dead:beef --> 2a00:1450:4007:804::1014
>>>> 16 bytes from 2a00:1450:4007:804::1014, icmp_seq=0 hlim=57 time=4.461 ms
>>>> 16 bytes from 2a00:1450:4007:804::1014, icmp_seq=1 hlim=57 time=4.462 ms
>>>> 16 bytes from 2a00:1450:4007:804::1014, icmp_seq=2 hlim=57 time=4.405 ms
>>>> ^C
>>>> --- www.google.com ping6 statistics ---
>>>> 3 packets transmitted, 3 packets received, 0.0% packet loss
>>>> round-trip min/avg/max/std-dev = 4.405/4.443/4.462/0.027 ms
>>>> ===
>>>>
>>>> Either way, you might want to have a look at OVH's guide [1] but in my own case, using a /56 was, at the time, the only way to get things working in a clean way.
>>>>
>>>> [1] http://help.ovh.com/Ipv4Ipv6#link10
>>>>
>>> I read this, I made sure to read this and then I read it a second time.
>>> No where does it indicate the use of a /56. I am in the process of a
>>> migration from an old OVH server to a new OVH server. My old box uses
>>> the /56 prefix length "fix" but based on the documentation this is
>>> incorrect and IMO this assumes that anyone else in the /56 is in the 
>>> same segment as me and if they are using /64 - well, There Be Dragons.
>>>
>>> Also from the information I have received, router advertisements may be
>>> turned off in the future, my host should simply Neighbour Solicit for
>>> the global scope unicast address of my default gateway. And as pointed
>>> out in previous emails without ACCEPT_RTADV for re0 - FreeBSD does not
>>> perform this action.
>>>
>>> So again, what is the correct way ? I think this is a debate of IPv6
>>> Protocol vs. IPv6 Policy vs. Network architecture.
>>>
>>> I'll go and get Tina Turner. You get Masterblaster and we'll meet in
>>> Thunderdome.
>>>
>>> C.
>