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Ios query. posted 09/13/2004
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I need to do the following
A router has two interfaces..

One interface is connected to an stm-1 and the other interface is a fast ethernet interface.

I also have a paralell router with the exact same interfaces sitting right be side it..

Both stm-1 interfaces on both routers are connected to stm-1 mux.. Both ehter interface are coonected to a swith..

One stm-1 is active, - the other is not... Both stm-1 intfaces on both routers  have the same ip address..

Note: the stm-1 interfaces can not see each other..(Ie no hsrp) on stm-1 interfaces.. - from transmission side both stm-1 interfaces can't be active at the same time.. its one or the other

If the active fibre fails, the trnasmission is flipped to the other router.. Who's stm-1 is configured and unshut and ready to go..
the flip over happens and all is well..

If the stm-1 connection is lost between the mux and the active router, the transmission path is flipped over to the other stm-1 in the other router , which becomes active..

The trnasmission flip is reliant on the stm-1 mux identifying loss of signal from the router etc and flipping to the transmission fibre to the other routers stm-1.

Now the problem arrises when an ethernet interface fails on the active router.  No loss of signal is detected on the transmission side as it knows nothing about the ethernet interfaces failing. No flip over happens. All it sees is the stm-1 is active and it appears fine.

What I would like happen is if the ethernet interface failed it would shut down the stm-1 interface as well, thus loss of signal would occur on the transmision side and the flip over would happen to the backup stm-1 on the other router...

Is this possible to do..
If not is there another solution you could propose..

CCIE #13037

Paul Casey 

Core Networks 
O2 (IRL)
Phone: +353 1 6096822
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Email: paul.casey@xxxxxx 

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