An application scales to 600 servers; each server needs a production subnet in 10.0.0.0/8. Which interface IP/mask on the router gives enough hosts while minimizing wasted addresses?

The application requires 600 servers, meaning each subnet needs at least 600 usable host addresses. A subnet mask of 255.255.252.0 (a /22 prefix) provides 2^(32-22) - 2 = 2^10 - 2 = 1024 - 2 = 1022 usable host addresses. This is the smallest subnet that can accommodate 600 hosts, thus minimizing wasted addresses. 255.255.254.0 (/23) provides 2^9 - 2 = 510 usable hosts, which is insufficient. 255.255.240.0 (/20) provides 2^12 - 2 = 4094 usable hosts, which is far more than needed and wastes many addresses. 255.255.255.240 (/28) provides 2^4 - 2 = 14 usable hosts, which is severely insufficient.