Microsoft DHCP has a scope: one CIDR, a range, exclusions, reservations, options. Lattice splits that into objects so the drawing (IPAM) and the server (DHCP) cannot disagree.

This page is the first hour in the console. Relays: relays. Reservations vs excludes: reservations, excludes. Helpdesk: helpdesk. Lease time (1-day default): DHCP lease time.

Just show me the steps — click path and prove-lease at the bottom.

1. Prefix vs subnet vs pool

Lattice	Rough Microsoft / ISC equivalent	What it is
Prefix	Superscope / “we own this block”	The plan. A `/16` on the drawing. Not a DHCP listener.
Subnet	The scope’s network + mask + router	One L3 network (`10.20.20.0/24`). Mode DHCP or Tracking only.
Pool	The dynamic range	Addresses dhcpd may Offer. No pool → no Offer.
Don’t offer / exclude	Exclusion range	Gateway, VIP, holes. dhcpd will not hand these out.
DHCP client	Reservation	This MAC always gets this IP.
Static server	A note in a spreadsheet	IP + hostname, no DHCP. Counts on the license.

A Microsoft “scope 10.20.20.0 mask 255.255.255.0 range .100–.200” becomes:

Prefix 10.20.0.0/16 (or 10.20.20.0/24 if you have no parent plan)
Subnet 10.20.20.0/24, gateway 10.20.20.1
Don’t offer .1 (and .254 if that is a VIP)
Pool .100–.200

The subnet CIDR must contain the relay’s giaddr (usually the gateway). The pool is only the dynamic slice. Do not invent a subnet that is only .100–.200 — giaddr .1 will not match.

2. Click path (DHCP VLAN)

Addresses → add a prefix (the block on the drawing).
Add a subnet inside it. Mode DHCP. Set gateway / VLAN / site if you have them. Lease time defaults to 1 day — leave it for campus; guest VLANs are hours, not 30 minutes (DHCP lease time).
Open the subnet (click the CIDR). Add address → Don’t offer the gateway. Single IP: leave end blank.
DHCP tab → add a pool. DHCP will not Offer until this exists.
Option 6 = DNS servers the laptop should query (usually your DCs), same as Microsoft scope option 006. Lattice does not fill this when you enable DDNS. dns-how.
More → Settings → Trusted relays: add the L3 switch / firewall IPs that will ip helper-address here. Empty drops relayed DHCP. relays.
Point one helper at this VM (or the HA VIP). Do not dual-helper Windows DHCP and Lattice on the same VLAN.

Tracking only (server VLAN)

Mode Tracking only. No pool. dhcpd ignores the subnet. Add address → Static server (hostname). Each assignment counts on the license cap.

3. Prove a lease

A pool on the map is not a lease. You need a DHCP packet.

Best: a relay, then a real client (or ipconfig /renew on a test VLAN).

On the Ubuntu VM (SSH), if you have no relay yet:

lattice-dhcptest -server 127.0.0.1:67 -giaddr 10.20.20.1

-giaddr must be an address inside the subnet CIDR (the gateway you typed is the usual choice). Overview should show a live lease, not only Expired.

A Windows laptop on the same VLAN as Community dhcpd sending a broadcast Discover often never arrives (Docker). That does not mean the install failed. relays.

4. What success looks like

Overview live count moved
Leases shows the MAC
Work is empty (or you understand why it is not)
Option 6 on a client (ipconfig /all) is the DCs you intended, not a surprise

Who held an address last Tuesday is More → History. The whole VLAN last Tuesday is As of on this subnet’s address map. History.

Names in DNS are a later adapter. Ack never waits. integrations.

Just the steps

Addresses → prefix (the block) → subnet inside it, mode DHCP, gateway set. Lease time defaults to 1 day.
Add address → Don’t offer the gateway (leave end blank for one IP).
DHCP tab → pool. Option 6 = the DCs (or whatever laptops already query).
More → Settings → Trusted relays → the helper IPs. Empty drops relayed DHCP.
One ip helper-address at this VM (or the VIP). Not Windows DHCP and Lattice.

lattice-dhcptest -server 127.0.0.1:67 -giaddr 10.20.20.1

-giaddr must sit inside the subnet CIDR. Overview should show a live lease. Same-VLAN broadcast to Community Docker dhcpd often never arrives — use a relay.