Current configuration
Windows 2003 server standard edition – domain controller role (nodeB)
Windows 2008 server R2 standard edition – domain controller role (nodeV)
Windows 2008 server (R1) standard edition – exchange server 2007
Windows 2008 server (R1) standard edition – terminal services role
Windows 7 clients
Windows 8.1 clients
Domain function level is Windows 2003 server
Forrest function level is Windows 2003 server
Proposal
The hardware supporting the windows 2003 server domain controller nodeB will be replaced with nodeC below on which 2012 server R2 standard edition will be installed:
PowerEdge R210 II Chassis, 2×3.5" Cabled HDDs, LED Diagnostics
Intel® Core™ Processor I3-3240, 2C/4T, 3.40GHz, 3M cache, 55W TDP
8GB Memory (4x2GB) 1600Mhz
2x1TB, SATA, 3.5-in, 7.2K RPM Hard Drive / RAID 1 with PERC H200
PERC H200 RAID Controller for 3.5" Cabled HD Configuration (compatible with 2012 server)
UEFI BIOS
16X DVD+/-RW ROM Drive SATA with SATA Cable
Questions
Compatibility between the hardware components and server 2012 making up nodeC is confirmed.
Where I need help please is regarding active directory compatibility support with existing servers detailed above and the role out procedures for 2012 DC promotion / demotion of 2003 DC.
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Question 1. With my current configuration in mind any software / OS / domain compatibility issue if adding a 2012 domain controller to this mix ? (domain function level domain/forest remains unchanged at 2003).
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Question 2. Same as question 1 but with the domain/forest function level raised to 2008 ?
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Question 3. Rough roll our procedure:
- A. deploy Windows 2012 server R2 standard edition on new nodeC.
- B. add the domain controller role / promote.
- C. confirm AD replication with existing 2008 DC nodeV
- D. demote nodeB (2003 DC) and remove from the domain.
- E. raise domain function level to 2008 server.
Best Answer
No, there are no compatibility issues caused by simply adding a new domain controller to a domain/forest.
The only impact that raising the domain/forest functional level has is adding new features... and preventing you from running a domain controller with an older operating system in that domain/forest.
From a Technet blog titled
What is the Impact of Upgrading the Domain or Forest Functional Level?:To summarize, the Domain or Forest Functional Levels are flags that tell Active Directory and other Windows components that all DCs in the domain or forest are at a certain minimal level. When that occurs, new features that require a minimum OS on all DCs are enabled and can be leveraged by the Administrator. Older functionality is still supported so any applications or services that used those functions will continue to work as before -- queries will be answered, domain or forest trusts will still be valid, and all should remain right with the world. This projection is supported by over eleven years of customer issues, not one of which involves a case where changing the Domain or Forest Functional Level was directly responsible as the root cause of any issue. In fact, there are only cases of a Domain or Forest Functional Level increase failing because the prerequisites had not been met; overwhelmingly, these cases end with the customer's Active Directory being successfully upgraded.
That's the correct order to do things in, yes.