A server administrator is setting up a new set of hosts for an application that requires communication between all the hosts on a dedicated private subnet.
Initially, the configuration consists of four hosts and is expected to grow to 48 total as the application is implemented for the entire company.
When configuring the private subnet, which of the following CIDR netmasks would allow for the full number of hosts once the application is fully in production with the least number of unused addresses allocated?
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A. B. C. D.B.
To determine the correct CIDR netmask for the private subnet, we need to calculate the maximum number of hosts that the subnet can support. The CIDR netmask determines the size of the subnet and is expressed as a number of bits. The larger the number of bits, the smaller the subnet size, and vice versa.
We are given that initially, there are four hosts, but the application is expected to grow to 48 hosts in total. To calculate the number of hosts required, we need to find the smallest power of 2 that is greater than or equal to 48. This is 64, which requires 6 bits to represent all possible hosts.
Now, we need to choose the CIDR netmask that will accommodate 64 hosts with the least number of unused addresses. The formula to calculate the number of hosts in a subnet is 2^(32 - n), where n is the number of bits in the netmask.
Using this formula for each of the options given:
A. /25 = 2^(32-25) = 2^7 = 128 hosts (more than required) B. /26 = 2^(32-26) = 2^6 = 64 hosts (exact number required) C. /27 = 2^(32-27) = 2^5 = 32 hosts (too few hosts) D. /28 = 2^(32-28) = 2^4 = 16 hosts (too few hosts)
Therefore, the correct answer is B. /26, which will allow for the full number of hosts (48) once the application is fully in production with the least number of unused addresses allocated.