CPU redundancy with two CPU412-2DP and one ET200L

How do I do This????

We are into PLC training and intend to show CPU Redundancy on Siemens S7 412 2DP cpu's.

I have following Hardware

(a) Rack UR2H with 18 slots. 6ES 400-2JA00-0AA00 split backplane bus

(b) Two power supply modules, PS 407 4A

(c) Two CPU 412Dp. 6ES7 412-2Xj05-0AB0

(d) ET200L 6ES7 133-1BL0.0XB0 ( 16 DI 16 DQ)

(e) Set of Profibus cables and piggiback connectors.

(f) USB MPI adapter and cables.

Slot 1 Power supply, slot 2 CPU (MPI 2, Prof 2), Next section Slot 1 Powwer supply, slot 2 CPU ( MPI 3, Prof 3)We have installed Simatic Manager ver 5.4 and SWR software.
What is in our mind is as follows. The programm for IO's on ET200L to be downloaded to both CPU's. One should be master and another standby. In event of main CPU going to fault/ prg mode , other CPU should run programm for these IO's.

Suggestions/sample code WELCOME

BMP of hardware is attached.
Representative image only, Not to be confused with exact Hardware

OB Blocks

Put those OB's to work 67,120,121 (hardware faults,software faults, memory overflow, scan time etc) plus a hardwire heartbeat that is a one output from PLC1 flashing to one input on the other PLC2. If PLC1 goes down (you decide the level of what down is) you take over with PLC2. You can write a book of software on what level you want to take over. Is it when you have a hardware fault, software, external device, etc?
If you write software "my way" and I have time I will reply again. Keep in mind that I have been recuperating from 2 years of vacantion and I just rejoined the workforce.

Y-LINK ([IM153HF+IM153HF]+Y-LINK) or redundancy ET200M ([IM153HF+IM153HF] + SM DI + SM DO)
see inside Step7 folder ~C:\Siemens\Step7\S7MANUAL\S7HVSYS\S7hvsysb.pdf



Example for MPI
How can you connect an operator panel directly to an H system without using repeaters?
http://support.automation.siemens.com/WW/view/en/23842653

i have few comments on all answers :



1-the used cpu is not an H cpu so we are talking about software redundancy , the software redundancy package does not appear in the solution .

2- i am not sure if it is possible to use ur2h rack with an non h system

3- Y couplers are not used for software redundancy

4- For using single ET it should have two interfce modules , one connected to each CPU.

Thanks Hasan

1. I want o go for only CPU redundancy i.e. if one goes in fault/stop mode, other should go to RUN.
2. UR2H rack can work with non H CPU.