TL;DR; Explains how updating DNS and Service Principal Names (SPNs) in Active Directory enables secure Windows Authentication connections to SQL Server instances.

OK, I now have the additional SPN’s added to AD that I mentioned in my post and a listing returns:
C:>setspn [servername]
Registered ServicePrincipalNames for CN=[servername],OU=Member Servers,DC=[domain],DC=biz:
MSSQLSvc/spdata.ep-dev.[domain].biz:1422
MSSQLSvc/spdata.ep-dev.[domain].biz:1433
MSSQLSvc/[servername].[domain].biz:1422
MSSQLSvc/[servername].[domain].biz:1433
SMTPSVC/[servername]
SMTPSVC/[servername].[domain].biz
HOST/[servername].[domain]onet.biz
HOST/[servername]
So when I now try to log into SQL server using spdata.ep-dev.[domain].biz/EPDev and Windows Authentication, all is well and I can connect to the server.
When I try moving the databases I will need to move this SPN to the new SQL Cluster, and it should work there as well.
Here’s hoping…
Technorati Tags: SP 2007
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