SUM in calculated item formula with dynamic params

[daftu]

I'd like to measure monthly total bandwidth usage by some ethernet interface, always starting from 1st day of month.
Normally if I wanted to create item with relative last 30 days summary i'd type: "sum(ifInOctets[eth0], 2592000)" (2592000 seconds = 30 days).

But I want always calculate bandwidth from 1st day of current month until now.
I created another item, returning number of seconds back to 1st day of current month, lets call it "sectill1st".

Then modified calculated item to "sum(ifinOctets[eth0], last(sectill1st)). Unfortunately item became unsuported (cannot evauluate function "sum...").

Is this possible to use dynamic value as sum second parameter?
Or maybe there is some other way to count monthly bandwidth?

Regards,

[tiagorsa]

I'd like to measure monthly total bandwidth usage by some ethernet interface, always starting from 1st day of month.
Normally if I wanted to create item with relative last 30 days summary i'd type: "sum(ifInOctets[eth0], 2592000)" (2592000 seconds = 30 days).

But I want always calculate bandwidth from 1st day of current month until now.
I created another item, returning number of seconds back to 1st day of current month, lets call it "sectill1st".

Then modified calculated item to "sum(ifinOctets[eth0], last(sectill1st)). Unfortunately item became unsuported (cannot evauluate function "sum...").

Is this possible to use dynamic value as sum second parameter?
Or maybe there is some other way to count monthly bandwidth?

Regards,

Did you find the solution? I have the same problem

[daftu]

Did you find the solution? I have the same problem

No, I gave up. But a few versions of Zabbix has been released until this post, so maybe it’s possible now.