The invention relates to a data packet transmitting method and a device of
virtual machine network, wherein the method comprises analyzing and obtaining source
host machine IP address and source
virtual machine MAC address and storing to a data base when a
physical network card is monitored to be provided with a data packet which is to be transmitted to a local
virtual network card, analyzing and obtaining a destination
virtual machine MAC address when the
virtual network card is detected to be provided with the data packet which is to be transmitted to network, judging whether the destination virtual
machine MAC address is
broadcasting MAC address or not, if the destination virtual
machine MAC address is
broadcasting MAC address, calculating and obtaining a
multicast IP address as a destination
host machine IP address, if not, inquiring in the data base and obtaining IP address as destination
host machine IP address, if the address can not be found, then, calculating the
multicast IP address as the destination host
machine IP address, and setting the destination host machine IP address into the data packet. The device comprises a module for executing the method. The invention adopts a
unicast and
multicast combined mode to transmit data in virtual machine network, lowers bandwidth load, and improves the transmission efficiency of the data packet.