I'm trying to get my head around the config needed to dynamically fail over to a backup link. All sites are using SRX240 running Junos 12.3.
Head office has vlan.10 assigned 10.1.0.0/24. Its SRX has this in stub area 0.0.0.1 as a passive interface.
Between head office and site1 is a layer 3 link serviced by ge-0/0/0.0 on both SRX. ge-0/0/0.0 on both is set in ospf area 0.
site1 uses vlan.10 as its local lan with ip range 10.2.0.0/24. vlan.10 is in stub area 0.0.0.1
Between site1 and site2 is a fast, but intermittent, link connectected to interface ge0/0/2 on each site's SRX
site2 uses vlan.10 as its local lan with ip range 10.3.0.0/24. vlan.10 is in stub area 0.0.0.1
site2 has a satellite backup link to head office. The SRX at site2 connects ge-0/0/3 to the satellite. The SRX in head office connects ge-0/0/3 to the satellite. The satellite link is up all the time. However we want to set the SRX at site2 to prefer its link to site1 as the path back to head office and only use the satellite if the site1 to site2 link is down.
What would the ospf config look like to achieve this?