Hi MagicPowerSun1257-1290,
Question 1. Since Server1 is down, I guess the PowerShell cmdlets have to be executed on the "slave" server? Server2?
As I know, both servers are okay. For reference, this article gives a detailed guide for Skype for Business pool failover & failback.
Question 2. How to plan for DNS? FQDN of each server, do we have to have two records of each - pointing to both standard edition servers?
About DNS, it needs to configure DNS to redirect Skype for Business Server web traffic to your disaster recover (DR) and failover sites. For more details, please refer to https://technet.microsoft.com/en-us/library/mt346420.aspx.
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