Start of the range every 10 minutes

I would like to set the start of the range every 10 minutes (eg. 0,10,20,30,40,50 min), and show only first 30 sec from the start point. (Because only the first half of every tenth minute contains an important changes for me, and I would like to show on a graph.)

It is working with start of the range evrey 1 minute (now/m), or 1 hour (now/h) or 1 day (now/d) on the From: field in the Time range menu.

I would like to set it to now/10m, but it couldn’t save it.

How can I set it?

now/10m should work, looks like a validation issue bug.

and show only first 30 sec from the start point.

That is going to be tricky. no idea how or what database supports that

Sorry, I would like to use the now/10m/m…