How to automatically switch routes between two ISPs in Juniper srx?

Question

Computer networks

There are two ISPs.
ISP1 and ISP2. Routes to them are of different cost. interfaces on them pp0.0 and pp0.1
How to make it so that if one ISP is unavailable, the route switches to another, moreover, ISP1 is a priority. Those. If ISP1 is not available, does it switch to ISP2, and when access appeared through ISP1, did the route return to it?
Tried creating a policy load-balance per-packet, but I'm not sure if that's what it takes. It's kind of like balancing.
Or at least direct to Google, with the right request.
Thank you.

Answer 1

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