S7 400H PLC with redundant profinet Interface Module

Dear All, 

As per plant requirement , we need to have redundant PLC processor as well as redundant IM module. Maximum IO count will be 350nos to 400nos.
I have idea of redundant CPU with single profinet IM module. Same system is running successfully. But now as the requirement is that IM module should be redundant too along with redundant CPU, I am little bit confused how to do that one with available CPU and IM.

CPU MLFB No: 6ES7412-5HK06-0AB0
IM MLFB No: 6ES7155-6AU01-0CN0
IO Modules are 6ES7131-6BH01-0BA0, 6ES7132-6BH01-0BA0, 6ES7134-6GD01-0BA1, 6ES7135-6HD00-0BA1, 6ES7134-6JF00-0CA1 and 6ES7134-6JD00-0CA1.

I have attached a typical architecture for your reference. Please let me know attached architure will work or not and switch can be managed or unmanaged. Also let me if there are any information I have to consider for the same.