Upgrade from 9.14 to 9.16 - transfer-source with low source port no longer works.

sthaug at nethelp.no sthaug at nethelp.no
Tue May 26 09:55:33 UTC 2020

> please see release notes:
> https://downloads.isc.org/isc/bind9/9.16.3/RELEASE-NOTES-bind-9.16.3.html
> This is listed in Known Issues for BIND 9.16.1:
>> 	• UDP network ports used for listening can no longer simultaneously be used for sending traffic. An example configuration which triggers this issue would be one which uses the same address:port pair for listen-on(-v6) statements as for notify-source(-v6) or transfer-source(-v6). While this issue affects all operating systems, it only triggers log messages (e.g. "unable to create dispatch for reserved port") on some of them. There are currently no plans to make such a combination of settings work again.

Also noted in the thread starting at


Steinar Haug, Nethelp consulting, sthaug at nethelp.no

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