Hi Chrizzieej ,
Do you want to configure 3 default routes with 3 different default gateways?
if yes ,you need 2 routing instances for each interfaces interfaces.
For Network 1 should have 192.168.100.254 as an gateway
set routing-options static route 0/0 next-hop 192.168.100.254
For network2
set routing-instances test1 interface ge-0/0/1
set routing0-instances test1 routing-options static route 0/0 next-hop 192.168.200.254
For network 3:
set routing-instances test2 interface ge-0/0/2
set routing0-instances test2 routing-options static route 0/0 next-hop 192.168.0.254
Then if you need communication between each routing instances , then you need share the routes using import and export of routes as per this KB :
http://kb.juniper.net/InfoCenter/index?page=content&id=KB19787&smlogin=true
Assign each interfaces to security zones and configure security policies to allow or deny traffic.
Hope this helps....
Regards
rparthi
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