Hello Mike @soylentgreen and Barry @Barry_Twycross1250
Thank you for the continued insights. These various DNS settings and functions are more complex than I had imagined; it will require me to go away and do a little studying to make better sense of your comments, then take action. Thanks for the encouragement… as the saying goes, “you don’t know what you don’t know.”
On a positive Barry’s tip on Quad9’s retirement of HTTP/1.1 accelerated my Peplink ticket to light speed. As soon as I pointed that out to the support agent, the issue was escalated and a few hours later I received an incremental firmware update which solved the issue, allowing me to use Quad9 for DNS-over-HTTPS without issue.
I should also note that Quad9 now works whether I use the Peplink preset, or do a custom entry:
https://dns.quad9.net/dns-query
9.9.9.9
149.112.112.112
Peplink subsequently confirmed that their preset uses that same flavor of Quad9’s service, but I prefer to see the info, rather than relying on the preset which does not display an actual URL in the UI.
Cheers