The most efficient subnet mask for a point-to-point heartbeat connection between two servers using IP addressing is /30. A /30 subnet mask has 255.255.255.252 as its decimal representation and 11111111.11111111.11111111.11111100 as its binary representation. This means that there are only two bits available for the host portion of the IP address, which allows for four possible combinations: 00, 01, 10, and 11. However, the first and the last combinations are reserved for the network address and the broadcast address, respectively. Therefore, only two IP addresses are usable for the point-to-point connection, which is the minimum required for such a link.A /30 subnet mask is also known as a point-to-point prefix because it is commonly used for point-to-point links between routers or servers1.
A /28 subnet mask has 255.255.255.240 as its decimal representation and 11111111.11111111.11111111.11110000 as its binary representation. This means that there are four bits available for the host portion of the IP address, which allows for 16 possible combinations. However, two of them are reserved for the network address and the broadcast address, respectively. Therefore, 14 IP addresses are usable for the subnet, which is more than needed for a point-to-point connection and would result in wasted addresses.
A /29 subnet mask has 255.255.255.248 as its decimal representation and 11111111.11111111.11111111.11111000 as its binary representation. This means that there are three bits available for the host portion of the IP address, which allows for eight possible combinations. However, two of them are reserved for the network address and the broadcast address, respectively. Therefore, six IP addresses are usable for the subnet, which is still more than needed for a point-to-point connection and would result in wasted addresses.
A /32 subnet mask has 255.255.255.255 as its decimal representation and 11111111.11111111.11111111.11111111 as its binary representation. This means that there are no bits available for the host portion of the IP address, which allows for only one possible combination: all ones. Therefore, only one IP address is usable for the subnet, which is not enough for a point-to-point connection and would result in an invalid configuration.
Therefore, a /30 subnet mask is the most efficient choice for a point-to-point heartbeat connection between two servers using IP addressing because itprovides exactly two usable IP addresses withoutwasting any addresses or creating any conflicts1.
