[scott_karana]

> The corrected DNS will take 4 hours to propagate.

This misconception bothers me a lot. DNS changes are complicated: there's no "n" where "n = the amount of time where any domain will magically be fixed".

"Propagation" is based on the configured TTL values of the specific DNS records requested, for the specific zone. Add in layers of application/OS/intranet/ISP/DNS provider caching, and it's a complicated nightmare to fix/predict reactively.

Most BIND9 installations use 86400 seconds by default: 24 hours. And some domains use more, some less, some have dynamically generated TTLs to simulate changing of records at a set/recurring wall clock time, instead of a time to live, some DNS caches are reset frequently, some caches retain values much longer than allowable by TTL...

[niels_olson]

Yes, I have configured BIND before. True, true, and still, most of the time, in my humble, limited experience, it will clear in well under 4 hours.