Mapping subnets in different virtual networks using private address space

A cloud computing system comprising a first virtual network and a second virtual network, comprising:

• one or more processors;
• and
• a virtual network management service that facilitates communication between a first resource in the first virtual network and a second resource in the second virtual network, the first resource running on a first host machine having a first host machine address, and the second resource running on a second host machine having a second host machine address, the virtual network management service comprising instructions that are executable by the one or more processors to:
• map a first subnet in the first virtual network to a second subnet in the second virtual network such that resources in the first subnet and the second subnet are able to communicate with each other;
• place the second resource in the second subnet of the second virtual network;
• create a representative resource in the first subnet of the first virtual network, wherein the representative resource corresponds to the second resource in the second subnet of the second virtual network;
• create a plurality of mappings comprising:
• a first mapping between a representative resource address and the second host machine address, wherein the representative resource address corresponds to the representative resource in the first subnet;
• a second mapping between the representative resource address and a resource address corresponding to the second resource in the second subnet;
• and
• a third mapping between an address of the first resource in the first virtual network and a source address that is associated with the second virtual network;
• encapsulate a data packet that originates from the first resource in the first virtual network based at least in part on the first mapping, the encapsulating being performed by a first networking stack running on the first host machine;
• perform network address translation at the second virtual network based at least in part on the second mapping and the third mapping, the network address translation being performed by a second networking stack running on
• the second host machine, the network address translation producing a translated data packet;
• and
• cause the translated data packet to be delivered to the second resource in the second subnet.

A non-transitory computer-readable medium that is configured to facilitate communication between a first resource in a first virtual network and a second resource in a second virtual network, the first resource running on a first host machine having a first host machine address, and the second resource running on a second host machine having a second host machine address, the computer-readable medium comprising instructions that are executable by one or more processors to:

• map a first subnet in the first virtual network to a second subnet in the second virtual network such that resources in the first subnet and the second subnet are able to communicate with each other;
• place the second resource in the second subnet of the second virtual network;
• create a representative resource in the first subnet of the first virtual network, wherein the representative resource corresponds to the second resource in the second subnet of the second virtual network;
• create a plurality of mappings comprising:
• a first mapping between a representative resource address and the second host machine address, wherein the representative resource address corresponds to the representative resource in the first subnet;
• a second mapping between the representative resource address and a resource address corresponding to the second resource in the second subnet;
• and
• a third mapping between an address of the first resource in the first virtual network and a source address that is associated with the second virtual network;
• encapsulate a data packet that originates from the first resource in the first virtual network based at least in part on the first mapping, the encapsulating being performed by a first networking stack running on the first host machine;
• perform network address translation at the second virtual network based at least in part on the second mapping and the third mapping, the network address translation being performed by a second networking stack running on the second host machine, the network address translation producing a translated data packet;
• and
• cause the translated data packet to be delivered to the second resource in the second subnet.