10-29-2020 07:50 AM
10-29-2020 08:02 AM - edited 10-29-2020 08:06 AM
So it will be a two-step process as the 2003 domain controllers will need to be gone and FRS->DFSR migration will need to be done.
I'd use dcdiag / repadmin tools to verify health correcting all errors found before starting any operations. Then stand up the new 2016, patch it fully, license it, join existing domain, add active directory domain services, promote it also making it a GC (recommended), transfer FSMO roles over (optional), transfer pdc emulator role (optional), use dcdiag / repadmin tools to again verify health, when all is good you can decommission / demote old one.
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