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dns over https configuration issue

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  • Last reply by Mace2

Mace2
Mace2
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If I place in the /general/network settings/ -Enable DNS over https the value of "https://mozilla.cloudflare-dns.com/dns-query" and place a fake DNS server IP on my workstations DNS such as 100.100.100.100 (not a DNS server) as apposed to 8.8.8.8 should Firefox be able to resolve network sites?

I had this configuration initially and it worked then stopped today Nov-26-2018. See below configuration from firefox and cloudflares "https://cloudflare-dns.com/help/" test.

If I place in the /general/network settings/ -Enable DNS over https the value of "https://mozilla.cloudflare-dns.com/dns-query" and place a fake DNS server IP on my workstations DNS such as 100.100.100.100 (not a DNS server) as apposed to 8.8.8.8 should Firefox be able to resolve network sites? I had this configuration initially and it worked then stopped today Nov-26-2018. See below configuration from firefox and cloudflares "https://cloudflare-dns.com/help/" test.
Attached screenshots

Chosen solution

I have found a solution. DNS over https ddoes not rely on the workstations local DNS as long as network.trr.mode is set to a value of 3. If network.trr.mode is set to 2 you cannot tell as it will fal back to your hosts DNS if a resolution failure occurs

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Mace2
Mace2 Question owner
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mace2 said

If I place in the /general/network settings/ -Enable DNS over https the value of "https://mozilla.cloudflare-dns.com/dns-query" and place a fake DNS server IP on my workstations DNS such as 100.100.100.100 (not a DNS server) as apposed to 8.8.8.8 should Firefox be able to resolve network sites? I had this configuration initially and it worked then stopped today Nov-26-2018. See below configuration from firefox and cloudflares "https://cloudflare-dns.com/help/" test.

I have noticed that firefox 63.03 will no long resolve requests immediately after a clear history of all components is performed. Is this a known bug?

Mace2
Mace2 Question owner
more options

Chosen Solution

I have found a solution. DNS over https ddoes not rely on the workstations local DNS as long as network.trr.mode is set to a value of 3. If network.trr.mode is set to 2 you cannot tell as it will fal back to your hosts DNS if a resolution failure occurs