No need to preserve agent IPs across this deploy — nothing outside a
container depends on a specific agent IP. Simpler approach: subtract
DHCP_POOL_SIZE from the usable count before hashing so agents only ever
land in [2, usable - DHCP_POOL_SIZE + 1], never in the DHCP pool.
Removes the secondary-hash remap block (~10 lines). Returns None for
subnets too small to hold both agent slots and the pool (edge case;
practical subnets are /24).
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