Exchange 2010 Hybrid - Server Roles Requirement

[Vineet Arora]

Hi,
 
We have an Exchange 2010 SP3 environment with 2 mailbox servers in DAG and 1 CAS/HUB server which is also configured for Hybrid.
 
Migration is completed and we want to remove the mailbox servers and keep only 1 server CAS/HUB for management as well as we want to keep email routing (both internet incoming and outgoing) via on premises exchange.
 
My question is, can I just go ahead and uninstall mailbox servers and we are left with 1 server with CAS and HUB roles and is also hybrid server? or I should install mailbox role as well on Hybrid server before remove mailbox servers/DAG?
 
I have read that for Hybrid management only CAS role is sufficient, I am keeping HUB because of email flow & connectors and thinking of also installing mailbox role because complete email routing is still via on premises, we do have some transport rules too. not 100% sure of it will impact anything.
 
Any advice will be appreciated.

[#2]

Hi @Vineet Arora,

The best approach to have your goal is to migrate your Exchange 2010 to Exchange 2016 and you will be full supported.

[#3]

Hi @Nuno Silva Thank you for response.

What about the licensing if we migrate to Exchange 2016? As per below article, we are not entitled for Hybrid key if we have a valid Exchange 2010 or 2013 license.

https://support.microsoft.com/en-in/help/2939261/how-to-obtain-an-exchange-hybrid-edition-product-ke...

[#4]

Hi @Vineet Arora,

For that response only Microsoft could answer to you. You can open a support ticket on your Office 365 and ask them that. You can also validate if you are eligible to a license here http://aka.ms/hybridkey