What Grafana version and what operating system are you using?
v9.5.1 docker image on CentOS
What are you trying to achieve?
Am trying to add the current time as an annotation line on a time series chart spanning now-12h to now+12h.
How are you trying to achieve it?
Similar to this post, but am using a Prometheus data source for this panel (the back end is actually VictoriaMetrics).
I have been attempting to make a comparable annotation for the Prometheus data source, but have not been able to find a syntax that gives me a single annotation line.
For instance, I though that
tlast_change_over_time(mqtt_value[1m])would return a timestamp for the most recently updated
mqqt_valuemetric, but what I get is an annotation line every 15mins up to the current time.
Thanks in advance for any pointers!