Are there any updates on this case?
I've experience the same issue when I configure DoT in Unbound with Quad9 Servers even when I only enable 1 Server (ex. 9.9.9.9). Most times, the issue is reproducible (no DNS resolution for any DNS-client; SERVFAIL in Log) after running the following DNS-Checker: https://dnscheck.tools
Thanks for your update.
I've experience the same issue when I configure DoT in Unbound with Quad9 Servers even when I only enable 1 Server (ex. 9.9.9.9). Most times, the issue is reproducible (no DNS resolution for any DNS-client; SERVFAIL in Log) after running the following DNS-Checker: https://dnscheck.tools
Thanks for your update.
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