Alertmanager version? Try logging into the same host where alertmanager runs, and running the following:
openssl s_client -connect smtp-relay.gmail.com:587 -starttls smtp ehlo mydomain.com mail from:<[email protected]> See if you get an error like this: 550-5.7.0 Mail relay denied [<address>]. Invalid credentials for 550-5.7.0 relay for one of the domains in: mydomain.com (as obtained from HELO and 550-5.7.0 MAIL FROM). 550-5.7.0 Email is being sent from a domain or IP address which isn't registered 550-5.7.0 in your G Suite account. Please login to your G Suite account and 550-5.7.0 verify that your sending device IP address has been registered within 550-5.7.0 the G Suite SMTP Relay Settings. For more information, please visit 550 5.7.0 https://support.google.com/a/answer/6140680#maildenied One possibility is that your host has gained a new external IP address (on IPv6 perhaps?) which has not been registered. -- 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/1b720448-b7d5-468b-ae36-60e2d718d8d8o%40googlegroups.com.
