Cisco’s blog entry 2022-02-10
https://umbrella.cisco.com/blog/enhancing-support-dns-encryption-with-dns-over-https
announces that their core resolvers now support DoT as well as DoH, effective
2022-01-28. Since they list the same IP addresses as OpenDNS, and identical
DoH resolvers https://dns.opendns.com/dns-query and
https://dns.umbrella.com/dns-query, the implication is both dns.opendns.com and
dns.umbrella.com should work as DoT resolvers! Verified both work for DoT on
an Android 10 smartphone with Google Chrome.
[Method: Disable DoH in Google Chrome (so it won't interfere): (3-dots)
Settings > Privacy and security > Use secure DNS = Off. Then set DoT on the
operating system: Settings > Network & internet > Advanced > Private DNS >
radio button "Private DNS provider hostname" = dns.opendns.com > Save. Use
Google Chrome to visit https://welcome.opendns.com, proving OpenDNS is in
effect. Then ditto for DoT DNS server dns.umbrella.com, visiting
https://welcome.umbrella.com successfully. Optionally re-enable DoH in Google
Chrome (which supersedes DoT when browsing): Privacy and security > Use secure
DNS = On > radio button "Choose another provider" > pulldown "OpenDNS". Using
a Google Pixel (1st. generation) phone, running LineageOS 17.1 (Android 10),
with Google Apps installed.]
