On the EX: DHCP Server
root@EX4200_TOR_SELab> show arp | match 30:b6:4f:21:02:80
30:b6:4f:21:02:80 172.30.95.208 172.30.95.208 vlan.141 permanent
...
root@EX4200_TOR_SELab> clear dhcp server binding 172.30.95.208
On the SRX:
set interfaces ge-0/0/2 unit 0 family inet dhcp
set security zones security-zone untrust screen untrust-screen;
interfaces fe-0/0/2.0 host-inbound-traffic system-services dhcp