https://kb.juniper.net/InfoCenter/index?page=content&id=KB31821&cat=SRX_SERIES&actp=LIST
A typical configuration for DHCP relay:
set forwarding-options dhcp-relay overrides bootp-support set forwarding-options dhcp-relay server-group relay-server z.z.z.z set forwarding-options dhcp-relay group prod-server active-server-group relay-server set forwarding-options dhcp-relay group prod-server interface rethX.Y