If I understand correctly, prometheus doesn't send any "resolved" message to alertmanager: it just stops sending alerts. Alertmanager treats the lack of alert as meaning "resolved".
Therefore, if you receive the "resolved" message, then this proves that alertmanager must have received the original alert. Hence you need to check the alertmanager logs to determine why it couldn't send out the original alert E-mail. -- 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/817dade8-5e0f-4692-a45b-6d594602b904%40googlegroups.com.
