There exists an asymmetric routing scenario that is similar to that at AWS.
Description of Problem :
This issues is realized when :
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With all of these pieces in place, packets sent from campus to the external IP will return to campus via the ExpressRoute and be dropped by the initiating host.
Solution: To get around or avoid this issue:
- we create two subnets in the customer VNet - one "private", one "public".
- a user defined route (UDR) will need to be created and then associated with the public subnet.
- The UDR will list all campus IP ranges with a next hop of "Internet".
Caveat: an additional caveat exists with this "solution":
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