R1:

system {

    host-name Juniper-Router1;
    root-authentication {
        encrypted-password "$1$xEA5AdLY$THIYYJpFK5vkrzeoV8s.K/"; ## SECRET-DATA
    }
    syslog {
        user * {
            any emergency;
        }
        file messages {
            any notice;
            authorization info;
        }
        file interactive-commands {
            interactive-commands any;
        }
    }
}
interfaces {
    em0 {
        unit 0 {
            family inet {              
                address 12.1.1.1/24;
            }
        }
    }
    lo0 {
        unit 0 {
            family inet {
                address 1.1.1.1/32;
            }
        }
    }
}
routing-options {
    max-interface-supported 0;
}
protocols {
    ospf {
        area 0.0.0.0 {
            interface em0.0;
            interface lo0.0;
        }
    }
}

 

R2:

system {

    host-name Juniper-Router2;
     root-authentication {
        encrypted-password "$1$cG36BMh9$AI5XHh5KdVZZCjmnFe9ib0"; ## SECRET-DATA
    }
    syslog {
        user * {
            any emergency;
        }
        file messages {
            any notice;
            authorization info;
        }
        file interactive-commands {
            interactive-commands any;
        }
    }
}
interfaces {
    em0 {
        unit 0 {
            family inet {              
                address 12.1.1.2/24;
            }
        }
    }
    lo0 {
        unit 0 {
            family inet {
                address 2.2.2.2/32;
            }
        }
    }
}
routing-options {
    max-interface-supported 0;
}
protocols {
    ospf {
        area 0.0.0.0 {
            interface em0.0;
            interface lo0.0;
        }
    }
}

测试：