Design IP allocations for a GKE cluster initially 5 nodes scaling to 10 nodes, max 8 Pods per node, and services growing from 100 to 1024. Choose the optimal primary and secondary ranges for nodes, Pods, and Services.

For nodes, a /28 (16 IPs) is sufficient for 10 nodes, allowing for future growth and upgrades. For Pods, 10 nodes 8 Pods/node = 80 Pods. A /24 (256 IPs) provides ample room for growth beyond the initial 80 Pods and allows for future increases in Pods per node. A /25 (128 IPs) would also work but offers less buffer. For Services, 1024 services require a /22 (1024 IPs). A /21 (2048 IPs) is unnecessarily large, while a /25 (128 IPs) or /28 (16 IPs) are too small. Therefore, a /28 for nodes, /24 for Pods, and /22 for Services is the most optimal.