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Subnet and VLAN Provisioning Planner

Give the planner your site's container prefix, any existing allocations, and the VLANs you need (name plus size). It carves non-overlapping subnets with next-fit allocation, assigns the first usable address as the gateway, and renders IOS XE configuration you can paste straight into the switch: VLAN and name, SVI, DHCP excluded address range, and a DHCP pool with network, default router, DNS, and lease.

Open the Planner

What it does

Frequently asked

What does the planner take as input?

A container prefix for the site, any subnets already in use, and the VLANs you need, each with a name and a size.

How are the subnets chosen?

Next-fit allocation inside the container, with no overlaps and natural alignment respected. Size each VLAN by host count or by an explicit prefix length.

What config does it produce?

Ready-to-paste IOS XE: the VLAN and name, the SVI with the first usable address as the gateway, a DHCP excluded range for the static block, and a DHCP pool with network, default router, DNS, and lease.