Network interface "Bits received" is cumulative instead of per second

[xofer]

Somehow one of my machine's incoming bits are cumulative:


Somehow, I doubt that it actually receives 80Gbps on a 1 Gbps link ;-)

The item is autodiscovered by "Windows by Zabbix agent" template.


The preprocessing does seem to define that it should be per second:


What am I missing?

Zabbix version is 7.0.6.

[Blevar]

This is a graph of bits recieved... It will grow the more data you download. This has nothing to do with network speed.

[xofer]

This is a graph of bits recieved... It will grow the more data you download. This has nothing to do with network speed.

As I posted, the "preprocessing steps" for the item says "Change per second" - does it not apply to the graph of the same item?
Anyway the main issue was that "Interface Intel(R) 82574L Gigabit Network Connection(Ethernet): High bandwidth usage" was triggered on this item shortly after starting and stayed until next reboot.

[xofer]

Here is a graph from a different host, different NIC. Same "Windows by Zabbix agent" template. This is what I would expect.

[cyber]

But what causes it to drop to 0 sometimes? Reboots?
Maybe that NIC gives out some weird values? Still that "change per sec" should avoid constant growth... "test all steps", what that shows? reasonable values ?

[xofer]

But what causes it to drop to 0 sometimes? Reboots?
Maybe that NIC gives out some weird values? Still that "change per sec" should avoid constant growth... "test all steps", what that shows? reasonable values ?

Yes, drops are restarts.
Maybe, but I got restless and changed the NIC (it was in a VM) from Intel to virtio and now it is normal.
What baffled me the most was that it wasn't even strictly cumulative - it went up and down with a cumulative trend as you can see from graph.