Re: [DNSOP] Risk of using underscores for sentinel (Was: A conversational description of sentinel.

Vladimír Čunát <vladimir.cunat+ietf@nic.cz> Mon, 12 February 2018 15:25 UTC

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Subject: Re: [DNSOP] Risk of using underscores for sentinel (Was: A conversational description of sentinel.
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On 02/12/2018 12:28 PM, Stephane Bortzmeyer wrote:
>> Current Firefox 58.0.1 and old Chromium 61.0.3163.79, Linux, same
>> result.  The system resolver does fetch _www.ksk-test.net. OK.  (I
>> can't say I understand what happens.)
> Isn't is simply because some browsers rely on the standard library's
> getaddrinfo() and this routine does not accept all domain names? On Linux:

Right, that's most likely the problem.  IIRC Firefox uses getaddrinfo
for DNS, at least on Linux.  Even if we discount Firefox, it would seem
better to choose names compatible with glibc's getaddrinfo.

--Vladimir