As for Q1: I do not know. But that does not really matter. Even if DNS is broken immediately after OPNsense boots, the cron job should eventually heal that condition. As I already stated, this should not be your main concern; you can shorten the recovery time simply by running the cron job more frequently.
What your experiments did establish quite convincingly is my earlier point about FQDN resolution causing problems with S2S connections.
Alas, you did not provide any of the diagnostic information I asked for that could actually shed light on what goes wrong when a C2S client cannot resolve DNS.
What your experiments did establish quite convincingly is my earlier point about FQDN resolution causing problems with S2S connections.
Alas, you did not provide any of the diagnostic information I asked for that could actually shed light on what goes wrong when a C2S client cannot resolve DNS.
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