Server 2008R2 AD+ DNS Upgrade

[karan_jhr]

Hi:

We are running Server 2008 R2 - Active Directory + DNS on one blade. We have primary & secondary DNS means AD1 and AD2 on two different blades

 

I want to upgrade the running AD1+DNS and AD2+DNS to server 2012 and want to go for upgrading the same blades instead of fresh installation

 

1 - Is it recommended?

2 - Since they are Live AD, what will be the case if AD1+DNS is upgraded to 2012 and AD2+DNS is still 2008?

3 - Shall i upgrade AD2+DNS then AD1+DNS or vice versa

 

thanks

[snagrat]

1) it is supported but personally I don't like doing upgrades.

 

2) Assuming you are only upgrading OS then no problem upgrading one before the other. Once both done you can look at upgrading the functional levels

 

3) shouldn't matter which way you do it.

[karan_jhr]

Do i need to backup DNS or it will be handled itself during upgrade?

[snagrat]

Handled by itself but I would always recommend you have a backup of at least one of the servers in case something goes wrong

[karan_jhr]

one last thing

after running

adprep /forestprep

adprep /domainprep

 

on AD1 and upgrading

Shall i run the same commands on AD2 as well before upgrading?

[snagrat]

No you won't have to as it will have already been upgraded via the first DC

[karan_jhr]

so for second AD i will straight upgrade the operating system

[snagrat]

Yes straight upgrade

[pantscat]

I wouldn't do an inplace upgrade, I'd do a fresh install and go straight for 2012R2 - it's better than 2012!

 

When you DCpromo the first DC it will check and do the adprep for you now.

 

Doesn't really matter what order you update them, just make sure that you demote them first!

[karan_jhr]

thanks it went smoothly

It took some time for AD2 to replicate but functional level has been raised to 2012R2 successfully

 

thanks a million