Re: Ping across auto IPV6 Tunnel - 50%

For what it's worth, there's also an IPv6 bug like this:

CSCsh63881 - "alternate ping success with NAT-PT and CEF enabled"

While no IPv6 PT in this example, it's still out there. (Workaround
is disable CEF, and it isn't fixed in any code yet).

-nick

On Tue, Sep 29, 2009 at 1:48 AM, Roy Waterman <roy.waterman_at_gmail.com> wrote:
> Hi Andrew
>
> By equal cost load balancing I was referring to the situation you had with
> your config with the router trying load balance but one of the static routes
> is dodgy :)
> Just as a rule, as Scott Morris likes to say, think like the router.
> Things become a lot clearer that way, at least, until the router behaves in
> unexpected ways!
>
> Glad you resolved the issue.
>
> 2009/9/29 ALL From_NJ <all.from.nj_at_gmail.com>
>
>> Hey team,
>>
>> Got this working tonight, auto ipv6 tunnels.
>>
>> Divin provided me this link:
>>
>> http://ardenpackeer.com/routing-protocols/tutorial-ipv6-tunnels-part-2-automatic-6to4-tunnels/
>> <-- this helped me much.
>>
>> Conceptually it helped me to consider this a 'hack' or 'cheat'. Kind of
>> neat in some ways too I guess ... by defining the IPv4 address as part of
>> the IPv6 address, you are really telling the router to find the remote peer
>> by it's IPv4 address. Of course ... the IPv4 routing table needs to be
>> right before this will work ...
>>
>> Any who ... my question is related to ping. Has anyone else seen 50% ping
>> timeout when using auto tunnels? I get all responses to other frame relay
>> ipv6 peers or Ethernet peers etc ... . Here is the output, kind of looks
>> like a pacing issue, but the fact that other pings work 100% of the time
>> does not make sense.
>>
>> R1(config)#do ping 2001:3:3:3::3 sou 2001:1:1:1::1 re 10
>>
>> Sending 10, 100-byte ICMP Echos to 2001:3:3:3::3, timeout is 2 seconds:
>> Packet sent with a source address of 2001:1:1:1::1
>> !.!.!.!.!.
>> Success rate is 50 percent (5/10), round-trip min/avg/max = 32/32/36 ms
>>
>> I have static routes going to the remote tunnel peer.
>>
>> Trace works just fine, no timeouts, single hop. I tried it with and
>> without
>> ipv6 cef. I also did a debug ipv6 pack det and debug ipv6 icmp ... nothing
>> out of the ordinary ...
>>
>> Any thoughts? Seen this?
>>
>> --
>> Andrew Lee Lissitz
>> all.from.nj_at_gmail.com
>>
>>
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>
>
> --
> Regards
> Roy
>
>
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Received on Tue Sep 29 2009 - 11:00:11 ART