How to set a time setting (once a month)

[Phelep]

Good morning all,
I am currently in the process of setting up supervision on the 4G data consumption of an external site.
For this, I created a calculation element with my two options (upload and download added). sum ("ifOutOctets [Example]", "30d") + sum ("ifInOctets [Example]", "30d")
I want to have an accumulation of data for the entire month, but which starts again from zero on the first of the month.
Currently my function is only recovering the last 30 days.
Do you have any leads to indicate instead of "30d" from every 1st of the month ???
I looked for the dayofmonth function, but couldn't find much information.
Thank you for your help.

[zhura]

did you found a way to start sum on first day of every month? i was also looking for dayofmonth function but yet unable to use it in calculated item formula field - getting error with "wrong parameter"

[Phelep]

Hello, Since my post, I have not found the solution. I have the same error message as you with the "day of month" function, I tried several other ways with mathematical functions but nothing functional

[zhura]

thanks for reply. please keep me posted if you reach any success

[cyber]

Latest version seems to support time shift of xM (x month).
For example here

https://www.zabbix.com/documentation/current/manual/config/triggers/expression

example 17......