IPv6- IDNet or Billion?

[Bill]

As a follow-up from this post- the bug hit again and I had no IPv6 this morning.

Symptoms:

Dual-stack sites hang (ie don't fall back to IPv4?), v4-only sites not affected (Need to check IPv6-only sites next time, both via browser and ping6, traceroute6 and anything else I can think of).

Occurrence:

Intermittent, but after between 3 days 10 hours and 3 days 18 hours of either router uptime or connection time (Which is the determining factor? Needs investigation, in hand.)

Available info:

1) Nothing out of the ordinary in the router log
2) Nothing out of the ordinary in router status pages
3) Nothing visible on my v6 BQM
4) Disconnect/reconnect fixes it, ie router reboot not needed (but this gives me a fresh IPv6 address)

Item 3) implies that incoming v6 connections are unaffected.

To me, this suggests (but doesn't confirm) the thought that there's a possible "stuck session" type of problem with IDNet's v6 nameservers. In principle, easily tested by using someone elses, eg OpenDNS, but with a non-repeatable problem that occurs at intervals of days it's less easy than it sounds!

It also requires a change in the router configuration, which is not a good idea for problem solving; basic rule- only change one thing at a time.

So... to anybody using native IPv6 (Steve and Seadog for starters ), any info as to this occurrence (or lack of it) with other routers or nameservers (or even ISPs) would be valuable.

Any other comments, something I've missed, suggestions etc?

[Steve]

I am keeping an eye on it Bill however re DNS does OpenDNS provide an IPv6 address as my usually change to OpenDNS gives an error on IPv6 test.

[jameshurrell]

See here Steve:

http://www.opendns.com/ipv6/

[Bill]

does OpenDNS provide an IPv6 address

It would seem that it does, thanks James- have a karma

Provided you add the IPs of the v6 nameservers... I'd assumed that it did because I thought the MacBook was set to use OpenDNS and it works fine, but when I went into Network Prefs and actually looked, I found that it was set to pick up its DNS from the router

But you've reminded me that the Macbook might be a useful extra way to check things when the problem occurs next time, so thanks for that

[Bill]

Now that's odd... I've changed the Macbook to use OpenDNS for both v4 and v6, and it seems to be working fine.

But test-ipv6.com says that my DNS server has no access to the IPv6 internet or is not configured to use it

Addresses I've used are:

208.67.222.222
208.67.220.220

2620:0:ccc::2
2620:0:ccd::2


Now wait to see what the Macbook does next time the iMac loses its IPv6...

[Steve]

Using the Network adaptor settings on my Macbook if I put the 2 OpenDNS IPv6 address at the top of the list with the IPv4 ones below I seem to be ok on test IPv6, if I place the IPv6 DNS below the IPv4 I get an IPv6 DNS failure.

I've just had to reconnect tonight as no IPv6 access using IDNet or OpenDNS names servers, not sure I'm any wiser as to whether it's firmware or IDNet issue.

[Bill]

I shuffled mine a bit-

v4 primary
v6 primary
v4 secondary
v6 secondary

and it seems to work OK.

I don't think that IPv6 test site is entirely bullet proof tbh... someone on tbb posted a World IPv6 Day test site: http://ipv6eyechart.ripe.net/

Usually all the sites come up green, occasionally one or two don't. I'm happy enough that it's mostly working

No loss of v6 here... Thursday afternoon is the critical time if my three and a half day bug is going to re-appear!

[Steve]

Well it's certainly a couple of days at least it maybe three since I reconnected to re establish IPv6 functionality.

[Bill]

If the problem recurs I've got a series of tests to do which may, or may not, help identify the cause but will at least provide more information.

If it doesn't recur then it's Plan B... when I work out what Plan B is

[Bill]

Hmm...

Using the IPv4/v6 speedtest at ipv6-test.com using the MacBook, wireless 'n' and OpenDNS:

IPv4: 29.4Mbps
IPv6: 29.6Mbps

Another one immediately afterwards on the iMac, wired connection and IDNet DNS:

IPv4: 11.8Mbps
IPv6: 6.9 Mbps

Something cock-eyed somewhere... I think that might be the basis for Plan B.

[Steve]

The power of WiFi 'N"


The DNS change shouldn't matter should it as the route will be the same unless OpenDNS is directing you to a nearer server than IDNet's DNS.

[Bill]

The power of WiFi 'N"

I rather walked into that one, didn't I?

The DNS change shouldn't matter should it as the route will be the same unless OpenDNS is directing you to a nearer server than IDNet's DNS.

Afaik the site only has one server for speedtests, in France. The routing might have been different I suppose, but I can't check 'cos I don't know it's IP address(es).

I'm a member of the forum there, if it looks a fruitful line of enquiry I'll ask some questions.

[Steve]

I've just tried myself on the Macbook (wifi) adslmax

OpenDNS IPv4 6Mbps
              IPv6 5Mbps

IDNetDNS IPv4 6Mbps
              IPv6 6Mbps

[Bill]

It's certainly not impossible that I was just unlucky... and I've seen good speeds before on the iMac.

When I've got past the 3 1/2 day mark that I'm waiting for, if necessary I'll run a series of back-to-back tests with each DNS on each computer and see what transpires.

I've got quite a lot of my download allowance left for this month

[Bill]

Well, the fault didn't manifest itself... but I found the following entry in the router log:

Code Select Expand

16/06/2011 21:23:36  home syslog[-1] Debug kill -15 2981
16/06/2011 21:23:36  home syslog[-1] Debug radvd -C /var/radvd.conf &
16/06/2011 21:23:36  home syslog[-1] Debug kill -15 2983
16/06/2011 21:23:36  home syslog[-1] Debug dhcp6s -c /var/dhcp6s.conf br0 &

at EXACTLY (to the second) 3.5 days after the last connect... intriguing.

Think I'll skip the tests I was going to do, and see if it's something that occurs twice a week.

But it's looking like it's the router, not IDNet.

(Or maybe a bit of both but router-initiated, if that dchp6s command fails?)