A program for making a computer function as a network monitoring device that monitors a state of a network having a plurality of terminals and network devices, wherein:
- the program makes the computer function as:
- a storage part, which stores:
- configuration information that includes interface address information identifying an interface address of a communication interface and a subnet mask length of the interface address, for each of the terminals and the network devices;
- and transfer destination information held by each of the network devices, including information that associates destination address information which identifies a destination address and a subnet mask length of the destination address with transfer destination address information which identifies a transfer destination address to which the destination address is to be transferred;
- an input receiving part, which receives, through an input part, designated destination address information that includes a designated destination address as an object of path information generation and a subnet mask length of the designated destination address;
- and
- a path information generation part, which performs:
- processing in which,
- from the transfer information of each network devices and for each piece of the destination address information, a network address of the destination address identified from piece of the destination address information is acquired as a first address,
- then, from the configuration information of each of the terminal, a network address of the interface address identified from the interface address information is acquired as a second address, and
- then, among the first addresses, each address that coincides with a plurality of the second addresses is identified as a branch network address, and address information that includes an identified branch network address and a subnet mask length of the branch network address is acquired as branch network address information;
- processing in which,
- from the configuration information of each of the network devices, a network address of the interface address identified from the interface address information is acquired as a third address,
- then, among the third addresses, an address coincident with the branch network address identified from the branch network address information is identified, and
- then, a network device having the interface address corresponding to the identified address is identified;
- and
- processing in which,
- by sequentially and repeatedly performing:
- first processing in which, from the transfer destination information of the identified network device, a transfer destination address to which the designated destination address identified from the designated destination address information should be transferred is acquired;
- and second processing in which, from the configuration information of each of the network devices, an interface address coincident with the acquired transfer destination address is identified, and a network device having the identified interface address is identified, to use then the transfer destination information of the identified network device in the first processing, path information that includes information specifying connection order of network devices between a branch network and the designated designation address is generated and
- the generated path information is stored in the storage part.