Hi,
You can configure rpm probes on the SRX to monitor reachability to a specific IP on the internet.
Syslog mesasges containing "PING_TEST_COMPLETED" and "PING_PROBE_FAILED" would be generated.
Please go through the following document for more details :-
https://kb.juniper.net/library/CUSTOMERSERVICE/technotes/RPM-to-SYSLOG-Reportingv1.0.pdf
Regards,
Sahil Sharma
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