So this last sentence would imply a 5xx response for misconfigured CSA SRV
records, and this tallies with common responses to bad MX records (if the
MTA software is paranoid enough to check them for RFC1918 addresses etc.).
A 5xx response is safer. As noted, this is not an "outage" problem or
anything that will self-repair.
However it would probably be helpful to add a NOTE that explains the choice.
To the extent the DNS geeks really object, the note will flag the issue, to
get their attention.
d/
---
Dave Crocker
Brandenburg InternetWorking
+1.408.246.8253
dcrocker a t ...
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