From marcoh at marcoh.net Mon Feb 1 11:21:53 2010 From: marcoh at marcoh.net (Marco Hogewoning) Date: Mon, 1 Feb 2010 11:21:53 +0100 Subject: Safari on IPv6 ? Message-ID: Morning Folks, This should be easy, however I can't seem to find the answer online as most articles are about turning off IPv6 instead of one. I noticed Apple's Safari 4.04 defaults to IPv4 instead of IPv6 when both A and AAAA are present. Now you can discuss wether this is a safe default or not, I would really like to know where the little button is to switch this behavior to AAAA first, which I recall used to be the case on earlier editions. Thanks, MarcoH (oh and please forget about browser wars, I know how to download Firefox) From jeroen at unfix.org Mon Feb 1 11:37:36 2010 From: jeroen at unfix.org (Jeroen Massar) Date: Mon, 01 Feb 2010 11:37:36 +0100 Subject: Safari on IPv6 ? In-Reply-To: References: Message-ID: <4B66AEF0.8000300@spaghetti.zurich.ibm.com> Marco Hogewoning wrote: > Morning Folks, > > This should be easy, however I can't seem to find the answer online > as most articles are about turning off IPv6 instead of one. > I noticed Apple's Safari 4.04 defaults to IPv4 instead of IPv6 when > both A and AAAA are present. Now you can discuss wether this is a safe It is ridiculous that that is a decision per-app instead of global. > default or not, I would really like to know where the little button is > to switch this behavior to AAAA first, which I recall used to be the case > on earlier editions. http://www.macosxhints.com/article.php?story=20090701234543632 aka: # defaults write com.apple.Safari IncludeInternalDebugMenu 1 and apparently there somewhere you can change it around... see http://www.macosxhints.com/article.php?story=20040112104026573 for more stories..... I don't have an true idea though as I don't use safari, but I hope the above helps you out > MarcoH > (oh and please forget about browser wars, I know how to download Firefox) But, but, did you think about Internet Explorer, Opera, Chrome and all the others out there? *nudge* :) Greets, Jeroen -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 196 bytes Desc: OpenPGP digital signature Url : http://lists.cluenet.de/pipermail/ipv6-ops/attachments/20100201/389b4700/attachment.bin From berni at birkenwald.de Mon Feb 1 11:44:18 2010 From: berni at birkenwald.de (Bernhard Schmidt) Date: Mon, 1 Feb 2010 11:44:18 +0100 Subject: Safari on IPv6 ? In-Reply-To: References: Message-ID: <20100201104418.GA2064@schleppi.birkenwald.de> On Mon, Feb 01, 2010 at 11:21:53AM +0100, Marco Hogewoning wrote: Note: this is only hearsay, some colleagues have this issue. > This should be easy, however I can't seem to find the answer online as > most articles are about turning off IPv6 instead of one. I noticed > Apple's Safari 4.04 defaults to IPv4 instead of IPv6 when both A and > AAAA are present. Now you can discuss wether this is a safe default or > not, I would really like to know where the little button is to switch > this behavior to AAAA first, which I recall used to be the case on > earlier editions. We have seen a similar behaviour with most applications after upgrading to MacOS X 10.6. It seems that the mdns-responder (?) of the system which is responsible for all DNS lookups is broken. It sends out both A and AAAA queries at the same time, but only seems to accept the first (successful?) response it gets. I've even heard that some people see the second UDP response from the cache is rejected with "Port unreachable". The effect is not a preference of IPv4, but no preference at all. Extremely hard to debug. Bugs have been filed with Apple several times, I can ask for the bug-ids. Best Regards, Bernhard From marcoh at marcoh.net Mon Feb 1 11:50:22 2010 From: marcoh at marcoh.net (Marco Hogewoning) Date: Mon, 1 Feb 2010 11:50:22 +0100 Subject: Safari on IPv6 ? In-Reply-To: <20100201104418.GA2064@schleppi.birkenwald.de> References: <20100201104418.GA2064@schleppi.birkenwald.de> Message-ID: <2FC3E83B-BC50-4558-8CEF-58B107D53CBC@marcoh.net> On 1 feb 2010, at 11:44, Bernhard Schmidt wrote: > On Mon, Feb 01, 2010 at 11:21:53AM +0100, Marco Hogewoning wrote: > > Note: this is only hearsay, some colleagues have this issue. > >> This should be easy, however I can't seem to find the answer online as >> most articles are about turning off IPv6 instead of one. I noticed >> Apple's Safari 4.04 defaults to IPv4 instead of IPv6 when both A and >> AAAA are present. Now you can discuss wether this is a safe default or >> not, I would really like to know where the little button is to switch >> this behavior to AAAA first, which I recall used to be the case on >> earlier editions. > > We have seen a similar behaviour with most applications after upgrading > to MacOS X 10.6. It seems that the mdns-responder (?) of the system > which is responsible for all DNS lookups is broken. It sends out both A > and AAAA queries at the same time, but only seems to accept the first > (successful?) response it gets. I've even heard that some people see > the second UDP response from the cache is rejected with "Port > unreachable". I can confirm it is either 10.6 or safari 4...not that I dig through traffic logs every day, just happen to notice it. > The effect is not a preference of IPv4, but no preference at all. > Extremely hard to debug. ssh seems to do the right thing, my ssh sessions are on 6 even tough the machine is listed with both AAAA and A but I might just got lucky on that one. > Bugs have been filed with Apple several times, I can ask for the > bug-ids. I'll try and kick them around a bit as well. In the meantime, Matthias suggestion seems to help, but again that might just be a lucky hit. MarcoH From andy at nosignal.org Mon Feb 1 12:05:30 2010 From: andy at nosignal.org (Andy Davidson) Date: Mon, 01 Feb 2010 11:05:30 +0000 Subject: Safari on IPv6 ? In-Reply-To: <2FC3E83B-BC50-4558-8CEF-58B107D53CBC@marcoh.net> References: <20100201104418.GA2064@schleppi.birkenwald.de> <2FC3E83B-BC50-4558-8CEF-58B107D53CBC@marcoh.net> Message-ID: <4B66B57A.2060303@nosignal.org> On 01/02/2010 10:50, Marco Hogewoning wrote: >> We have seen a similar behaviour with most applications after upgrading >> to MacOS X 10.6. It seems that the mdns-responder (?) of the system >> which is responsible for all DNS lookups is broken. It sends out both A >> and AAAA queries at the same time, but only seems to accept the first >> (successful?) response it gets. [...] > I can confirm it is either 10.6 or safari 4...not that I dig through traffic logs every day, just happen to notice it. [...] > ssh seems to do the right thing, my ssh sessions are on 6 even tough the machine is listed with both AAAA and A but I might just got lucky on that one. Oh no, this explains a change in behaviour that I have seen with xchat, which seems to connect to a v6 or v4 host at almost random. That's really bad. :-( Andy From nanog at 85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org Mon Feb 1 13:45:16 2010 From: nanog at 85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org (Mark Smith) Date: Mon, 1 Feb 2010 23:15:16 +1030 Subject: Safari on IPv6 ? In-Reply-To: References: Message-ID: <20100201231516.26bc585c@opy.nosense.org> On Mon, 1 Feb 2010 11:21:53 +0100 Marco Hogewoning wrote: > Morning Folks, > > This should be easy, however I can't seem to find the answer online as most articles are about turning off IPv6 instead of one. I noticed Apple's Safari 4.04 defaults to IPv4 instead of IPv6 when both A and AAAA are present. Now you can discuss wether this is a safe default or not, I would really like to know where the little button is to switch this behavior to AAAA first, which I recall used to be the case on earlier editions. > Are you using a 6to4/6in4 etc. tunnel? It might be that they've implemented RFC3484, "Default Address Selection for Internet Protocol version 6 (IPv6)", which by default prefers native IPv4 over tunnelled IPv6. Broadly that makes sense, as native connectivity is more likely to perform better and be more reliable, however, when you want to use IPv6 when ever it is available, regardless of native IPv4 status, you need to change source and destination preferences. One way to test if this is happening is if you're able to successfully go to an IPv6 only website e.g. ipv6.google.com, but connect via native IPv4 on websites providing both A and AAAAs, like www.kame.net. That was my symptoms with Firefox. I don't know how to change OSX, but under Linux you can change the behaviour by creating a file called /etc/gai.conf, with contents similar to the following (MRS lines are my additions from the default, as shown in http://linux.die.net/man/5/gai.conf). This fixed Firefox for me. -- # Used for selecting source addresses # # label