Cisco DHCP Option 43 Builder

Generate Option 43 hex for classic WLC discovery (F1), EWC conversion (F2), or Fast Offline Migration (F3), then export clean IOS / IOS-XE pool configs with byte-by-byte clarity.

Format summary

F1: `F1 <len> <WLCs>`

F2: `F2 <len> <WLCs>`

F3: `F3 <len> <WLCs> <mode>`

Hover each byte for context.

Mode & Output

DHCP Mode AP Mode (F3 only) Pool Name Reverse Decode (Option 43 Hex)

Paste full hex (with or without dots/spaces) to populate fields.

Network Inputs

Management VLAN Subnet (CIDR)

Required for IOS config output.

Default Gateway DNS Servers Domain Name

Lease Days Lease Hours Lease Minutes

WLC Input

Single WLC address; encoded as 4 bytes.

Hex Composition Rules

Classic Option 43 (F1)

Format: `F1 <length> <WLC-IP-ARRAY>`

Length = number of WLCs × 4 bytes

Example: `f1040a010b1f`

EWC Conversion (F2)

Format: `F2 <length> <WLC-IP-ARRAY>`

Length = (WLCs × 4) + 1

Example: `f205c0a88202`

Fast Offline Migration (F3)

Format: `F3 <length> <WLC-IP-ARRAY> <MODE>`

Length = (WLCs × 4) + 1 mode byte

Example: `f3050a010b1f02`