I have a juniper ins-phoenix (srx220h) firewall in my organization.
I have two ISP.
I want to set up the juniper firewall (which i am using as a router also) in such a way that whenever my ISP1 link goes down it should automatically connect to ISP2 and whenever ISP1 link comes back it should switch back over to ISP1.
Basically I want to make ISP2 as a backup connection so which connects by self.
Also I do not want to make any changes to the workstations. Actually they should not even notice that link of ISP1 is down.
Is this possible at all, if so how to achieve this and implement this.