Forum Discussion
decommision resource forest and install Exchange 2016 in account domain with existing hybrid
Following situation at a customer: - Account and Resource forest - Office 365 tenant - Azure AD Connect machine running in Account forest, syncing both directories - ADFS in Account forest - Ex...
Thanks Dominik. Although I have null experience in this, this is also what I thought would be the best approach. But unfortunately, the customer has already setup a hybrid with Ex2010 in their Resource domain, setup Azure AD Connect in the Account forest and migrated already users to EOL.
So, we need to do in this config, like described:
- Ex2010 in resource forest, Azure AD Connect in Account forest, Hybrid on Ex 2010 and already users migrated to EOL.
So the question, what global steps do I take to decommission the Resource forest? Thanks for helping me in advance!
The problem is that you should have been provisioned the migrated users to the Exchange 2016 resource forest prior migrate it to Exchange Online. You can't to this for Exchange Online mailboxes anymore.
1. Export all attributes from the Exchange Online migrated users from your on-premises Active Directory in the Exchange 2010 resource forest.
2. Migrate Cross-Premise to Exchange 2016.
3. Import the Exchange attributes in the new Exchange 2016 user account (except those which were moved with prepare moverequest, like homemdb, exchangeversion, etc.)
4. Stop AAD Connect.
5. Decomission hybrid: https://technet.microsoft.com/library/dn931280(v=exchg.150).aspx
5. Run AAD Connect in the new Forest
6. Set up hybrid
But this is not a overall supported solution, just my personal experience. And, of course, it is a very low level list which tasks must be performed.
I am working on a similar project with what sounds like an almost identical setup with the user/resoure forest and mailboxes have already been migrated to Office 365. We havent got to the stage yet where Exchange 2016 is installed in the user forest. My thoughts around the steps involved were as below:
1. Install EX2016 in user forest - Set SCP to null to prevent any Autodiscover funnys
2. Add Office 365 mail routing domain as remote domain in EX2016
3. Export Exchange attributes from resource forest account
4. Stop AAD connect
5. Remove resource forest acccount from AAD connect scope so it only syncs from user forest account
6. Import Exchange attributes to user forest account and run the new-remotemailbox command
7. Start AAD connect
8. Decommission hybrid from resource forest
9. Configure hybrid in user forest
I am plannnig to validate this process on a batch of test accounts first to see if any issues occur.
Richard,
Are these the attributes are important for the export and import?
EmailAddress
ProxyAddresses
msExchRecipientTypeDetails
msExchMailboxGuid
Or am I missing some attributes?
Accounts are already created and configured for SSO in the users forest.I will map the users with msExchMasterAccountSID and objectGuid
Are you decommissioning the Forest that has Exchange installed or will that remain?
One more question. You mentioned in step 1 to set the SCP to $null. Why is that? If I install Ex 2016 in the other forest, there is no SCP record yet, so this cannot be overwritten by the Ex2016 install. Why set it to $null? The SCP records (every CAS server has one) in the resource forest cannot be overwritten by the install in the other forest.
Thanks again!
Hi Olaf,
I agree with you, prior to the installation of EX2016 in the user forest there will be no SCP record and the work shouldnt affect the existing deployment in the other forest.
My plan was to set the SCP to null once the installation of EX2016 was completed, this was more of a precaution than anything else as all the Autodiscover DNS entries already point to exchange online. I am planning on doing some work this week on installing EX2016 so will report back if there are any issues.
Richard
Thanks guys. I will look at this and will discuss this hopefully this week or next week and will define the proper scenario for us.
Not the exact solution, should be similar to what the final goal is without the offboarding part.
https://www.itpromentor.com/offboarding/
Also worth a read
http://techgenix.com/off-boarding-email-office-365-exchange-2013-part1/
