Re: DNS resolution for apps vs Terminal?
Thanks for the answers. Sigh. A little more investigation showed that it had something to do with my router's DNS cache. Normally, it serves up itself as the DNS server for DHCP clients. When I reconfigured it to serve up Google's DNS servers instead, all apps started working normally. This was also reflected on my iPhone. At the time of the problem, images weren't loading in the Facebook app (it's unclear if the rest of the content I could see was just cached or successfully loaded at that time). Changing the DNS servers used immediately fixed that problem. I'm not sure what the differences between c-ares/dig and mDNSResponder are, in that one was able to look things up when using the router's DNS, and the other not. > On Jun 14, 2016, at 08:41 , Alastair Houghton > wrote: > > On 14 Jun 2016, at 15:13, Michael Nickerson wrote: >> >>> On Jun 14, 2016, at 5:11 AM, Rick Mann wrote: >>> >>> Just now Safari stopped being able to load facbook.com. So did Chrome. Both >>> reported DNS failures. >>> >>> But dig on the command line, and curl, both succeed. >>> >>> How are these two domains different? >> >> Safari and other apps are using the frameworks to resolve DNS (which, I >> believe, is ultimately done via mDNSResponder, but I could be wrong on that >> one), > > You’re correct. It does use mDNSResponder (you can actually see the code on > Apple’s Open Source site). > >> while command line programs are using lower level calls that query the DNS >> server directly. > > dig does its own DNS protocol over ordinary sockets. curl uses c-ares, an > open source DNS library. > > Kind regards, > > Alastair. > > -- > http://alastairs-place.net > -- Rick Mann rm...@latencyzero.com ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: DNS resolution for apps vs Terminal?
On 14 Jun 2016, at 15:13, Michael Nickerson wrote: > >> On Jun 14, 2016, at 5:11 AM, Rick Mann wrote: >> >> Just now Safari stopped being able to load facbook.com. So did Chrome. Both >> reported DNS failures. >> >> But dig on the command line, and curl, both succeed. >> >> How are these two domains different? > > Safari and other apps are using the frameworks to resolve DNS (which, I > believe, is ultimately done via mDNSResponder, but I could be wrong on that > one), You’re correct. It does use mDNSResponder (you can actually see the code on Apple’s Open Source site). > while command line programs are using lower level calls that query the DNS > server directly. dig does its own DNS protocol over ordinary sockets. curl uses c-ares, an open source DNS library. Kind regards, Alastair. -- http://alastairs-place.net ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: DNS resolution for apps vs Terminal?
> On Jun 14, 2016, at 5:11 AM, Rick Mann wrote: > > Just now Safari stopped being able to load facbook.com. So did Chrome. Both > reported DNS failures. > > But dig on the command line, and curl, both succeed. > > How are these two domains different? > Safari and other apps are using the frameworks to resolve DNS (which, I believe, is ultimately done via mDNSResponder, but I could be wrong on that one), while command line programs are using lower level calls that query the DNS server directly. ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: DNS resolution for apps vs Terminal?
Really facbook.com ? If so, maybe it's some kind of protection, the site is owned by MarkMonitor; perhaps there is a blocker on these things. On 14 June 2016 at 10:11, Rick Mann wrote: > Just now Safari stopped being able to load facbook.com. So did Chrome. > Both reported DNS failures. > > But dig on the command line, and curl, both succeed. > > How are these two domains different? > > -- > Rick Mann > rm...@latencyzero.com > > > > ___ > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > Please do not post admin requests or moderator comments to the list. > Contact the moderators at cocoa-dev-admins(at)lists.apple.com > > Help/Unsubscribe/Update your Subscription: > https://lists.apple.com/mailman/options/cocoa-dev/aandi%40quite.com > > This email sent to aa...@quite.com ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
