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DNS over https stops working

user226514887665625432230708206477982186438
user226514887665625432230708206477982186438
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While using DNS over HTTPS it stopped resolving. I have about:config set to network.trr.mode to 3 which relies only on the value in firefox "https://mozilla.cloudflare-dns.com/dns-query". Strangely it never recovers until I disable DNS over https. When I enable network.trr.mode changes to 2 which I change back to 3 and it starts working.

When I close Firefox 63.03 it and reopen it DNS over Https stops working until I perfrom the step above. The startup destination is 49176 to an address in luxumburg. see enclosed

Is this a known issue?

While using DNS over HTTPS it stopped resolving. I have about:config set to network.trr.mode to 3 which relies only on the value in firefox "https://mozilla.cloudflare-dns.com/dns-query". Strangely it never recovers until I disable DNS over https. When I enable network.trr.mode changes to 2 which I change back to 3 and it starts working. When I close Firefox 63.03 it and reopen it DNS over Https stops working until I perfrom the step above. The startup destination is 49176 to an address in luxumburg. see enclosed Is this a known issue?
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All Replies (4)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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I don't know whether DoH (TRR) is ready for use in current Firefox releases (it is under development), so it may not always work correctly. In case of issues you will have to disable this new feature.

McCoy
McCoy
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See also the questions you posted here :

/questions/1241830   and   /questions/1241882

(no replies)

user226514887665625432230708206477982186438
user226514887665625432230708206477982186438 Question owner
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OK. Becuase this issue occurs on a Linux workstation as well.

Is there a place I can report this issue?

user226514887665625432230708206477982186438
user226514887665625432230708206477982186438 Question owner
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update:

I am using DNS over https and have firefox 63 setup as follows -no proxy -Operating DNS system set up with a fake non responsive DNS value -The URL for DOH- https://mozilla.cloudflare-dns.com/dns-query

When I set Firefox to use network.trr.mode to a value of 3 which I understand to mean use only the DOH DNS values and do not fall back to any other, firefox fails to to resolve any sites. This worked prior to Dec-7-2018 but not anymore. Can you offer an explanation?