IPv6 Oddity

Post new topic   Reply to topic    DD-WRT Forum Index -> Broadcom SoC based Hardware
Author Message
sfixphdi
DD-WRT Novice


Joined: 04 Mar 2010
Posts: 27

PostPosted: Mon Jul 16, 2012 18:00    Post subject: IPv6 Oddity Reply with quote
Good day. I am running three routers:

2x WRT54G-TM with 19342
1x WRT54Gv4 with 18946M

On one of the WRT54G-TM routers, I have an IPv6 tunnel working perfectly and have not had any problems with it in years. On the second TM and on the v4, I have this same problem. IPv6 address seutp works fine and radvd works fine. However, when I ping a known IPv6 address or resolvable domain from any connected computer that has received an IPv6 address and route, I get "destination net unreachable":

Pinging google.com [2607:f8b0:4007:800::1001] with 32 bytes of data:

Destination net unreachable.
Destination net unreachable.
Destination net unreachable.
Destination net unreachable.

Ping statistics for 2607:f8b0:4007:800::1001:
Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

Next, if I shell into either router, and from the command prompt do a ping6, it always works 100%:

root@blahblah:~# ping6 google.com
PING google.com (2607:f8b0:4007:801::1008): 56 data bytes
64 bytes from 2607:f8b0:4007:801::1008: seq=0 ttl=59 time=12.431 ms
64 bytes from 2607:f8b0:4007:801::1008: seq=1 ttl=59 time=11.485 ms
64 bytes from 2607:f8b0:4007:801::1008: seq=2 ttl=59 time=13.115 ms

Now, if I go RIGHT AWAY and try the computer again, it works, but only for about 10 seconds. After that time, I get "destination net unreachable" again. I can go back and forth all day long, but the route only holds up for approximately 10 seconds. Yes, I did 30/30/30 before and after each firmware update on all three routers.

Why is this happening? And, even more interesting, why is it only happening on one of two routers that are the same model, run the same build, have IPv6 set up in the same manner, and utilize the same tunnel service?

Thanks for you assistance.
Sponsor
slobodan
DD-WRT Guru


Joined: 03 Nov 2011
Posts: 1555
Location: Zwolle

PostPosted: Mon Jul 16, 2012 18:52    Post subject: Reply with quote
Use some DNS server with IPv6 support, like OpenDNS, this way you are sure that the records are obtained the right way. Further, radvd should allocate IPv6 addresses to clients, you could do this if you have a subnet. Check for a firewall blocking IPv6 echo. Also check IPv6 connectivity with http://test-ipv6.com
_________________
2 times APU2 Opnsense 21.1 with Sensei

2 times RT-AC56U running DD-WRT 45493 (one as Gateway, the other as AP, both bridged with LAN cable)

3 times Asus RT-N16 shelved

E4200 V1 running freshtomato 2020.8 (bridged with LAN cable)

3 times Linksys WRT610N V2 converted to E3000 and 1 original E3000 running freshtomato 2020.8 (bridged with LAN cable)


Display posts from previous:    Page 1 of 1
Post new topic   Reply to topic    DD-WRT Forum Index -> Broadcom SoC based Hardware All times are GMT

Navigation

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum