A network device resolves a destination address of an endpoint in an endpoint isolation environment. The network device receives a request for a destination address associated with a destination endpoint. The request originates from an isolated source endpoint. The network device determines whether the destination address is stored on the network device in association with the destination endpoint. Responsive to a determination that the destination address is not stored in association with the destination endpoint, the network device generates a proxy request for the destination address, and sends the proxy request to at least one endpoint attached to the network device. The network device receives a proxy response from the destination endpoint that includes the destination address. The network device stores the destination address in association with the destination endpoint.