Some thoughts on Prometheus Alertmanager's alert reminders
utcc.utoronto.ca
utcc.utoronto.ca
Either something should file a bug to look at "some time later", or it should start ringing your phone.
Email alerts are just spam.
For both bugs and pages the reminder is good. A bug should get an update essentially saying "yes, this is still looking bad" (not create a new bug), and if it was important enough to page you the first time, then (unless you silenced the alert) it's important enough to remind you by ringing your phone again.
As for the dashboard, there’s an Alertmanager data source for Grafana that’s super easy to set up. If you have Grafana already I would just go ahead and do it since it takes maybe ten minutes.
What is a free self-hosted alternative to these two?
It now uses the Prometheus Alertmanager natively as its alert manager. And if you were using something like Mimir instead of Prometheus then you can seamlessly use Grafana against that Alertmanager too. Grafana is comfortable with any number of Prometheus compatible alert managers since the last major version.