Hi Toby, > >> this is exactly what we used as a solution. In the release notes of > >> connman 0.57 I found the hint that 0.57 should fix the bug > >> http://bugs.meego.com/show_bug.cgi?id=4818 ... after all it does not > >> fix the bug but at least it gave me the right idea. I've patched > >> connman's resolver.c to not add "options edns0" to rsolv.conf and this > >> fixed it. Now all issues with these special WiFi routers disappered. > >> > >> I guess this patch should also be added to upstream connman? > > > > this is serious problem. We need the EDNS0 support on one hand for the > > big DNS records to get them over UDP. On the other hand it seems to be > > heavily broken :( > > so what exactly is EDNS0 needed for? From what I can see here my > notebook which uses Network Manager has no "options edns0" in > /etc/resolv.conf, too. So maybe EDNS0 could be some kind of > configurable option in the expert-settings of connman or something > like that? But I guess it's important to disable edns0 by default > because otherwise connman will stop to work with the WiFi routers of > some of germany's major internet providers...
So EDNS0 allows bigger packets sent over UDP. It is an extension for the limited size of DNS result packets. This is needed if you have for example big results with a lot aliases or actual extras in TXT records etc. We enabled this by default since the assumption is that it is suppose to work since Windows 2000 and onwards enables this also by default. Maybe the Linux implementation of glibc is broken or just not that smart. The only other option is to run DNS over TCP. That would work as well, but it is not supported by all routers. Only a few actually implement DNS over TCP besides its UDP version. Seems like whatever we do right now, we get bug reports from the other side. So maybe it is time to redo this in a smart way and figure out EDNS0 support on the fly and disable it if needed. We could do this with our DNS proxy, but that is not something you just fix in a few days. Regards Marcel _______________________________________________ connman mailing list [email protected] http://lists.connman.net/listinfo/connman
