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IPv6 Hour at NANOG: A Follow-Up


I wrote in the previous post about IPv6 hour at NANOG, in which the dual-stacked wireless LAN would be shut down and all access would be via the IPv6-only wireless LAN; getting IPv4 destinations outside the LAN would be via NAT-PT.

It started off a little rough. Throughout the conference I had IPv4 turned off on my MAC and had been working just fine on the IPv6-only LAN. Admittedly I didn’t try many different online applications, just the things I use on a regular basis: Web browsing and e-mail. An I FTP’d some files to my editor at Cisco Press – all without difficulty.

But when the dual-stack LAN was shut down everything stopped working. Apparently when a few hundred people suddenly jumped to the IPv6-only LAN the Linux-based NAT-PT could not scale.

After a bit of “tweaking,” however, (I haven’t yet found out just what sort of tweaking was done), access came back up.

As Randy Bush announced at the beginning of the event while the NAT-PT was still down, sometimes a failure is more educational than a success. While overall the IPv6 Hour was not a failure, it did serve its intended purpose of helping to reveal problems at scale, problems that can then be taken back to vendors for resolution before you try implementing IPv6 on your own production network.

Among the problems revealed:

-       NAT-PT was supposed to be supported over both the Linux-based NAT-PT and Cisco’s NAT-PT. I’m told that the implementers could not get the Cisco NAT working, although that might have just been a configuration issue.

-       Windows XP, while supporting IPv6 packets, does not support IPv6 DNS. Therefore an RFC 1918 address and a local IPv4 DNS resolver had to be given to XP users for them to get online.

-       As I mentioned in the last post, MAC OS X does not support DHCPv6, so the IPv6 DNS addresses had to be entered manually.

-       IPv6 must be turned on in Thunderbird and Firefox browsers; it’s off by default.

All in all this was an enlightening event because any transition must, as a measure of success, be transparent to the end-users. In the case of IPv6, no one wants to hear that they need to do some special configuration on their PCs to get the same access they previously had without those special configurations.

For me, being a dedicated MAC user, I hope Mr. Jobs and Co. release a DHCPv6 patch or at least get it on the OS X roadmap real soon.

The IPv6 Hour will be tried again at APRICOT next week, and at the IETF in Philadelphia the week of March 10.

Rocky Mountain IPv6 Summit

The Rocky Mountain IPv6 Task Force will be holding its first Rocky Mountain IPv6 Summit in Denver on April 9th. We’re lining up a good group of speakers and a very informative agenda; if you’re in the Colorado-Wyoming-New Mexico region and want to know more about IPv6, I hope to see you there!

You can get more information, and sign up, at:

http://www.rmv6tf.org/SpringEvent.htm

IPv6 in FireFox and Thunderbird

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IPv6 is only disabled by default in FireFox and Thunderbird on Mac OS X. On other platforms, it's enabled by default.

The decision was made to disable it on Mac OS X because on 10.3, the getaddrinfo() function (the IPv6-aware libc function for converting hostnames to addresses) was broken. That function has been fixed in 10.4 and 10.5, so I think it may be worth submitting a patch to Mozilla to enable IPv6 by default.

MacOS Firefox and TBird

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it's not that FF and TB don't do V6, it is that they have V6 DNS disabled, goddesses know why. from the wiki

It appears that at least on Mac OS X (I don't have access to other platforms to check), the Firefox defaults have been changed to not look up AAAA records. To fix this, enter about:config in the URL box. Locate network.dns.disableIPv6 in the list. Double-click on it to change the value to false.

NAT-PT

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What's going on with NAT-PT? My understanding that was that it had been officially deprecated, but there don't seem to be any good alternatives for accessing an IPv4 internet resource from a IPv6-only client.

Just curious, why was DHCPv6

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Just curious, why was DHCPv6 required, as opposed to using stateless autoconfiguration?

Re: Just curious..

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DHCPv6 was needed to acquire the DNS addresses. That was my complaint about MAC OS, which is more an irritant than a serious technical issue: I had to enter the addresses of the DNS servers manually.

--Jeff 

Hey Jeff! Next time dont

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Hey Jeff! Next time dont leave your file sharing enabled at nanog. :)

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About Jeff Doyle

Jeff Doyle is president of Jeff Doyle and Associates, an IP network consultancy. Jeff is the author of Routing TCP/IP, Volumes I (read an excerpt) and II and of OSPF and IS-IS: Choosing an IGP for Large-Scale Networks. He is a frequent speaker on IPv6, MPLS, and large-scale routing.

Contact him.

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