Recording medium, management device, and network system

A management device comprising:

• a receiver that receives a tunnel connection command to connect a first virtual machine and a second virtual machine through a layer 2 tunnel corresponding to particular quality of service;
• a processor that generates
• a first command to instruct a first physical machine on which the first virtual machine is running and which is connected to a plurality of physical networks through a first physical network interface device to use a first address and a second address in encapsulating in a first layer 3 packet a first layer 2 frame that the first virtual machine decides to send to the second virtual machine, each of the plurality of physical networks supporting one or more levels in quality of service, both the first address and the second address corresponding to a particular physical network of the plurality of physical networks that supports the particular quality of service, the first address being one of a plurality of addresses assigned to the first physical network interface device, and the second address being one of a plurality of addresses assigned to a second physical network interface device through which a second physical machine on which the second virtual machine is running is connected to the plurality of physical networks, and
• a second command to instruct the second physical machine to use the second address and the first address in encapsulating in a second layer 3 packet a second layer 2 frame that the second virtual machine decides to send to the first virtual machine;
• and
• a transmitter that sends the first command to the first physical machine and sends the second command to the second physical machine.

A network system comprising:

• a first communication device connected to a plurality of physical networks each of which supports one or more levels in quality of service;
• a second communication device connected to the plurality of physical networks;
• a first physical machine which includes:
• a first physical network interface device which is assigned a plurality of addresses corresponding to the plurality of physical networks, and is connected to the first communication device;
• a first processor configured to
• run a first virtual machine,
• encapsulate in a first layer 3 packet a first layer 2 frame that the first virtual machine decides to send to a second virtual machine, and
• control the first physical network interface device to send the first layer 3 packet;
• and
• a first storage device configured to store a first source address and a first destination address for use in encapsulating the first layer 2 frame;
• a second physical machine which includes:
• a second physical network interface device which is assigned a plurality of addresses corresponding to the plurality of physical networks, and is connected to the second communication device;
• a second processor configured to
• run the second virtual machine,
• encapsulate in a second layer 3 packet a second layer 2 frame that the second virtual machine decides to send to the first virtual machine, and
• control the second physical network interface device to send the second layer 3 packet;
• and
• a second storage device configured to store a second source address and a second destination address for use in encapsulating the second layer 2 frame;
• and
• a management computer which is enabled to communicate with the first physical machine and the second physical machine, and includes:
• an input device from which a tunnel connection command is input or a reception device configured to receive the tunnel connection command, the tunnel connection command being a command to connect the first virtual machine and the second virtual machine through a layer 2 tunnel corresponding to particular quality of service;
• and
• a transmission device configured to
• send, to the first physical machine, first setting information that specifies a first address and a second address respectively as the first source address and the first destination address, wherein the first address is one of the plurality of addresses of the first physical network interface device and corresponds to a particular physical network which supports the particular quality of service, and the second address is one of the plurality of addresses of the second physical network interface device and corresponds to the particular physical network, and
• send second setting information that specifies the second address and the first address respectively as the second source address and the second destination address, to the second physical machine.