OK, if you get the slack alert 3 times too, that probably rules out an E-mail issue.
I think the next thing is to look at the stdout/stderr from alertmanager. If you are running alertmanager under systemd, then: journalctl -eu alertmanager -- 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/b6b59b41-6af1-498f-8041-2d1655ecd825o%40googlegroups.com.
