/27 the new /24

Mike mike-nanog at tiedyenetworks.com
Thu Oct 8 22:45:38 UTC 2015


On 10/08/2015 02:41 PM, Mark Andrews wrote:
>
>
> Plus one to that. We are such a provider, and IPv6 is on my list of
> things to implement, but the barriers are still plenty high. Firstly, I
> do have an Ipv6 assignmnt and bgp (v4) and an asn, but until I can get
> IPv6 transit,
>
> There are lots of transit providers that provide IPv6.  It really is
> time to name and shame transit providers that don't provide IPv6.

NO, THERE IS NOT. We operate in rural and underserved areas and WE DO 
NOT HAVE realistic choices. Can you see me from your ivory tower?

>> there is not much point in my putting a lot of effort into
>> enabling IPv6 for my subscribers. Yes I have a HE tunnel and yes it's
>> working, but it's not the same as running native v6 and with my own
>> address space. Second, on the group of servers that have v6 thru the HE
>> tunnel, I still run into problems all the time where some operations
>> over v6 simply fail inexplictly, requireing me to turn off v6 on that
>> host so whatever it is I'm doing can proceed over v4.
>> Stuff like OS updates for example.
> Then complain to the OS vendor.  It is most probably someone breaking
> PMTU discover by filtering PTB.  Going native will hide these
> problems until the MTU between the DC and the rest of the net
> increases.  You could also just lower the advertised MTU internally
> to match the tunnel MTU which would let you simulate better what a
> native experience would be.
Not my job. v4 works, v6 does not, end of story.

>
> I can't remember the last time I saw a site stall due to reaching it 
> over IPv6 it is that long ago.

It happens every day for me, which only amplifies my perception that v6 
IS NOT READY FOR PRIME TIME.

>> Damm maddening. Can't imagine the screaming I'll
>> hear if a home user ever ran into similar so I am quite gun shy about
>> the prospect. Secondly, the the dodgy nature of the CPE connected to our
>> network and the terminally buggy fw they all run is sure to be a never
>> ending source of stupidity.
> CPE devices are buggy for IPv4 as well.  Bugs in CPE devices are
> only found and fixed if the code paths are exercised.

Not my job. v4 works, v6 does not. I am a provider not a developer.
> That said IPv6 worked fine for me with the shipped image (old version
> of OpenWRT) using 6to4 before I reflashed it to a modern version
> of OpenWRT as I wanted to use the HE tunnel rather than 6to4.  I
> know that is only one CPE device.
  And will you be providing all of my end users with replacement CPE 
that meets all of the other requirements too? No? Because no such 
devices exist yet? OHHH yeah thats right, I'm a provider not a 
developer, so again, not a solution for my business.

>> Thirdly, some parts of my network are
>> wireless, and multicast is a huge, huge problem on wireless (the 802.11
>> varities anyways). The forwarding rates for multicast are sickeningly
>> low for many brand of gear - yes, it's at the bottom of the barrel no
>> matter how good or hot your signal is - and I honestly expect v6 to
>> experience enough disruption over wireless as to render it unusable for
>> exactly this reason alone.
> You expect but haven't tested.

Based on observation and experience, I think v6 will wipe out the 802.11 
portion of my network and no, Im not going to 'test' it, recovery would 
be near impossible and in any event I don't experiment with paying 
customers. I won't move until the underlaying issues are resolved, and 
that means fixing multicast in wireless, which won't be done by me again 
because, you guessed it, I am a provider and not a developer.
>> The wired portion of my subscriber network is only slightly better, im
>> pretty sure it can deal with v6 in the middle, but the question is still
>> wether specfic CPE models can and which set of bugs I'll hit on my
>> access concentrators passing our v6 over PPPoE. I just read about a
>> cisco bug where enabling rp-filtering on v6 causes a router reload,
>> which I would hit immediately since rp-filtering is a standard
>> subscriber profile option here (trying to be a good netizen). How many
>> other network destroying bugs await? The longer I wait on v6, the less
>> work I will have to do dealing with bugs. So, as the original posted
>> said, we'll do v6 when it's easy, when we have time, and when the
>> economics make sense.
> And is there a fix available yet?  All code has bugs in it.  They
> exist in both the IPv4 code paths and the IPv6 code paths.  There
> are lots of places that are going IPv6 only internally and only
> having IPv4 at the fringe.  You can't do that if routers are flakey
> when pushing IPv6 packets.  This is basically just fear overriding
> rational decisions.

I am a provider and not a developer, and I am likely only going to use 
what I know works and what is within my sphere of control and influence. 
The flakey crappy state of v6 today means I am not putting it out 
anywhere a customer would have any exposure to it. I don't play games 
with my customers that way.




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