i'm very sorry with boring you, maybe, but would like to have a clear idea about this.....
"... When using a virtual network as part of a cross-premises architecture, you need to make sure to carve out an IP address range that you can use specifically for this virtual network. If a duplicate address range exists on both sides of the VPN connection, traffic will route in an unexpected way. Azure VPN Gateway will NOT perform any NAT-like functionality on the inner packets to/from the IPsec tunnels and hence you can't have overlapping IP address ranges between Azure & local sites. ...... So to answer your query in simple terms: Why between two customers NOT using Azure this is possible : 3rd party VPN devices support NAT, hence this is possible. Why between two customers using Azure this is NOT possible : Azure VPN gateway doesn't support NAT, hence this is not possible. Kindly let us know if the above helps or you need further assistance on this issue. Please "Accept the answer" if the information helped you. This will help us and others in the community as well."
ok i understood that is not possible do it. as you said "....traffic will route in an unexpected way... ". ok i understood and have to accept it
but.... if this is possible for outside Azure, Why this is not possible inside Azure? Why Azure doesn't support NAT ?
is there a technical reason ?
security reason ?
technology limit ?
hope to be clear and once again sorry for pushing about a more technical answer
thks very much.
have a nice day, wonderful weekend