Hi aungzawtun,
"irb" interface can be used as source.
Sample management config in a transparent mode:-
set groups node0 interfaces fxp0 unit 0 family bridge interface-mode access vlan-id 20
set groups node1 interfaces fxp0 unit 0 family bridge interface-mode access vlan-id 20
set groups node0 interfaces irb unit 0 family inet address 192.168.1.1/24
set groups node1 interfaces irb unit 0 family inet address 192.168.1.2/24
set bridge-domains mgmt domain-type bridge vlan-id 20 routing-interface irb.0
set routing-options static route 0.0.0.0/0 next-hop 192.168.1.254
Regards,
Rahul