Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.
I see you have to resolve "failover group FQDN" and is failing.
I suggested the following questions/checklist.
- From where are you trying to resolve the FQDN?
- From VNetA or VnetB
- What do you mean by "failover group FQDN"?
- Is it the FQDN of the Private EndPoint of a secondary SQL Server?
- If so, do you have the Private DNS Zone integrated with the VM's VNet from where you are trying to resolve to?
- In case of a custom DNS server, the Private DNS Zone must be integrated to the Vnet that is hosting the DNS server (VnetA)
- Did you check if the Private DNS Zone that is integrated to the VNet has an entry for the secondary SQL Database?
You informed, your private DNS Zone wasn't linked to the Domain Server (AADDS) VNet and this was the issue.
Thanks,
Kapil
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