Managing communications in a virtual network of virtual machines using telecommunications infrastructure systems

A system, comprising:

• one or more computing systems of a telecommunications infrastructure provider, wherein the one or more computing systems include one or more hardware processors and associated memory that stores instructions that are executable on the one or more hardware processors to cause the one or more computing systems to:
• manage, using a communication manager, communications to and from a computing node in a virtual computer network of computing nodes,
• wherein the computing nodes are virtual machine instances hosted on physical hosts in a substrate network of the telecommunications infrastructure provider,
• wherein the communication manager is implemented on a first physical host of the physical hosts and includes a switch that physically connects to the substrate network,
• wherein to manage the communications to and from the computing node, the communication manager is configured to:
• store configuration information about the virtual computer network;
• receive, from the substrate network, a first communication addressed to the computing node hosted on the first physical host;
• based at least in part on the configuration information, modify the first communication and forward the first communication to the computing node;
• receive, from the substrate network, a second communication addressed to the computing node;
• and
• based at least in part on the configuration information, drop the second communication without forwarding the second communication to the computing node, and
• wherein the communication manager is further configured to:
• in response to an address resolution protocol (ARP) communication from the computing node regarding a second computing node in the virtual computer network, send a spoofed response to the ARP communication indicating a virtual hardware address of the second computing node.

One or more non-transitory computer-readable media storing program instructions that when executed on or across one or more processors of a telecommunications infrastructure provider cause the one or more processors to:

• manage, using a communication manager, communications to and from a computing node in a virtual computer network of computing nodes,
• wherein the computing nodes are virtual machine instances hosted on physical hosts in a substrate network of the telecommunications infrastructure provider,
• wherein the communication manager is implemented on a first physical host of the physical hosts and includes a switch that physically connects to the substrate network,
• wherein the management comprises to:
• store configuration information about the virtual computer network;
• receive, from the substrate network, a first communication addressed to the computing node hosted on the first physical host;
• based at least in part on the configuration information, modify the first communication and forward the first communication to the computing node;
• receive, from the substrate network, a second communication addressed to the computing node;
• and
• based at least in part on the configuration information, drop the second communication without forwarding the second communication to the computing node, and
• wherein the management further comprises:
• in response to an address resolution protocol (ARP) communication from the computing node regarding a second computing node in the virtual computer network, send a spoofed response to the ARP communication indicating a virtual hardware address of the second computing node.