Hello, few days ago I updated our recursive resolvers at AS50242 from Debian 10 to 11 to be able to enable stale-answer afer Facebook incident. However, today I got bug reports from customers. Their browser often fail at page loading with DNS_PROBE_FINISHED_NXDOMAIN. After few seconds (and after browser DNS re-query) page will load correctly. In Bind9 log I see many of messages like:
Oct 27 11:34:13 srv-snv-production named[576109]: configuration.ls.apple.com resolver failure, stale answer unavailable Oct 27 11:34:13 srv-snv-production named[576109]: client @0x7fc71806cd58 10.202.42.196#58876 (configuration.ls.apple.com): view clients: query failed (SERVFAIL) for configuration.ls.apple.com/IN/TYPE65 at query.c:5832 Oct 27 11:34:13 srv-snv-production named[576109]: configuration.ls.apple.com resolver failure, stale answer unavailable Oct 27 11:34:13 srv-snv-production named[576109]: client @0x7fc7180715a8 10.202.42.196#49219 (configuration.ls.apple.com): view clients: query failed (SERVFAIL) for configuration.ls.apple.com/IN/A at query.c:5832 After I turned off stale-answer, problem looks to be resolved. I'm attaching huge debug log of above failures - hope somebody will find problem from this. The problematic query starts at 27-Oct-2021 11:34:13.858 https://drive.google.com/file/d/1qiyLa8CfNN54PUktth6R4kT8PpohNsde/view?usp=sharing Linux srv-le-production 5.10.0-9-amd64 #1 SMP Debian 5.10.70-1 (2021-09-30) x86_64 GNU/Linux bind9/stable,now 1:9.16.15-1 amd64 Regards, Blažej Krajňák _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
