You haven't shown the most important bit, which is your blackbox_exporter config where you've defined the http_3xx module.
Also, show the result if you scrape blackbox_exporter manually using curl: curl 'localhost:9115/probe?target=https://foo.example.com&module=http_3xx' -- You received this message because you are subscribed to the Google Groups "Prometheus Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/prometheus-users/fa979928-52c3-4988-967c-6f4356c6efaao%40googlegroups.com.
