UncensordDNS and DNS brownout today

[Reynir Björnsson <reynirr@xxxxxxxxx>]

Dear list,

The default DNS server used in Mirage applications is
uncensoreddns.org. A while ago they announced that they would be
turning off DNS queries over plaintext and set today as the date[1].
We had heard a rumor this was on the table so we in Robur worked on
implementing DNS over TLS which we released in November[2].

If you are experiencing some of your unikernels failing to resolve
hostnames this may be why. Thankfully, today it is just a 12-hour
brownout and the real phase out will be on October 1[0].

Best,
Reynir

[0]: https://blog.uncensoreddns.org/blog/40-cleartext-dns-turned-off/
[1]: 
https://blog.uncensoreddns.org/blog/39-the-unfriendly-internet-turning-off-cleartext-lookups-in-september/
[2]: https://github.com/mirage/ocaml-dns/blob/main/CHANGES.md#v610-2021-11-10