There are two ways of configuring DHCP; Legacy and extended.
Both of these methods are valid. Legacy was created in an older version of Junos, while extended was updated to match across multiple platforms.
DHCP requires an active interface in the VLAN that addresses are being sent to
A juniper device can be configured as a dhcp server or a dhcp relay.
|set vlans NAME l3-interface INTERFACE||configuration||Associate a layer-3 interface with a VLAN|
|set system services dhcp-local-server group NAME interface INTERFACE||configuration||Enable DHCP server on an interface (extended config)|
|set access address-assignment pool NAME family inet network SUBNET||configuration||Create a pool (extended)|
|set access address-assignment pool NAME family inet range NAME low START-IP high END-IP||configuration||Create pool range (extended)|
|set access address-assignment pool NAME family inet dhcp-attributes router IP||configuration||Sets a gateway (extended)|
|set access address-assignment pool NAME family inet dhcp-attributes name-server IP||configuration||Set a DNS server (extended)|
|show dhcp server binding||operational||Show dhcp leases (extended)|
|show dhcp server statistics||operational||Show dhcp stats (extended)|
|set system services dhcp pool SUBNET address-range low START-IP high END-IP||configuration||Configure a DHCP pool (legacy)|
|set system services dhcp pool POOL routerIP||configuration||Sets a gateway (legacy)|
|set system services dhcp name-server IP||configuration||Set a DNS server (legacy)|
|show system services dhcp binding||operational||See dhcp leases (legacy)|
|show system services dhcp statistics||operational||Show dhcp stats (legacy)|
|set forwarding-options helpers bootp server IP||configuration||Set DHCP relay IP|
|set forwarding-options helpers bootp interface INTERFACE||configuration||Set the interface to use when contacting the DHCP server|
|show helper statistics||operational||DHCP relay troubleshooting information|