DHCP IN JUNOS: Apply this whole config, included dhcp server address. Seems not to work on fpx interfaces:

set interfaces ge-0/0/7 unit 0 family inet dhcp-client client-identifier prefix host-name
set interfaces ge-0/0/7 unit 0 family inet dhcp-client lease-time 86400
set interfaces ge-0/0/7 unit 0 family inet dhcp-client retransmission-attempt 6
set interfaces ge-0/0/7 unit 0 family inet dhcp-client retransmission-interval 5
set interfaces ge-0/0/7 unit 0 family inet dhcp-client server-address 10.5.0.1
set interfaces ge-0/0/7 unit 0 family inet dhcp-client vendor-id ether
set interfaces ge-0/0/7 unit 0 family inet dhcp-client options no-hostname

DHCP IN LINUX

• Remove the default gateway : External Link
• Remove the default gateway : options directly in libvirt net definition : External Link
• Vagrant libvirt has the dhcp configuration in: /var/lib/libvirt/dnsmasq/vagrant-libvirt.conf