We need a alert mail when there are no datapoints

I need to create an alert mail if there are no data points. We have the bunch of servers(250). We build grafana dashboard for these servers to check server health. In that for each server, we read CPU, RAM, and DISK space from each server. I need grafana alerts to trigger when there is no data streaming in any of the servers so that I can infer that the container is down. Currently, the graph just stops plotting and no alerts are triggered.
If the condition has “HAS NO VALUE” and there are no datapoint by any one of the servers. I need an alert mail, from that server we don’t get any data point.
Please help this. Thanks in advance.
This is my query:

Just change “If no data or all values are null” to “Alerting”.

I have changed the same, but it is not working.

I have changed the same. But it is not working. Can you please help us. Thanks!

As long as, at least one server returns a valid data, Grafana doesn’t raise an alert. On the page at https://grafana.com/docs/grafana/latest/alerting/create-alerts/ says:
“If a query returns multiple series then the aggregation function and threshold check will be evaluated for each series. What Grafana does not do currently is track alert rule state per series.”

Therefore it seems it’s not possible.

PS: I’m looking for a similar scenario. But couldn’t find any working solution except defining a query (therefore an alert) for each server!