ipv6 connectivity bugs

Mike mike-nanog at tiedyenetworks.com
Mon Oct 19 12:29:07 UTC 2015

On 10/19/2015 04:46 AM, Dave Bell wrote:
> Do you have anything in the way of COPP on either box that may be
> dropping packets? I would imagine the issue is likely to be on the
> AS1k end.
> Additionally I see you have different interface speeds at each side.
> Is the thing in the middle at fault? ND is done using multicast.
> One final thing is attempt to ping across the link local addresses.
> Make you you set the source address correctly.
I am able to ping the link local address of the 'opposite end' from each 
side, so it looks so me like that is working. I also notice, when I try 
pinging the 7201 from the asr1000, during that time, the output of 'show 
ipv6 neighbors" shows me this:

sh ipv6 neighbors
IPv6 Address                              Age Link-layer Addr State 
FE80::xxxx:yyyy:FE2D:D190                   6 xxxx.yyyy.d190  STALE 
xxxx:yyyy::1:1                              0 -               INCMP 

     It looks to me like enough is 'working' that the asr1000 -> c7201 
path is working, but not the other way around. And no, far as I know, I 
have no copp or other filtering that would (to my knowledge) create a 
one way situation. As far as the middle, I have ip/mpls that is bridging 
my vlan25 across the network:

! ME3600x - Facing ASR1000
Interface TenGigabitEthernet0/1
switchport trunk allowed vlan none
  switchport mode trunk
  mtu 9216
  service instance 25 ethernet
   encapsulation dot1q 25
   rewrite ingress tag pop 1
   xconnect 2 encapsulation mpls
    mtu 9216

! ME3600 - facing c7201
interface Vlan25
  mtu 9216
  no ip address
  xconnect 2 encapsulation mpls

Do I need to make a special provision somewhere for multicast? This 
seems pretty basic setup to me.


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