Items not generated from calculated item prototype

[nicodvb]

HI,
I'm trying to generate a calculated item from an item prototype.
In the discovery rule this is the definition of the prototype:

name: byterate
type calculated
type of information: numeric float
key: input_byterate
Formula:
{MYTPL:net.if.in[ifHCInOctets.{#SNMPINDEX}].delta(15m)}/900

Type numeric
units bps
update interval 60s
Create enabled: yes

The ifHCInOctets entry is gathered by SNMPv3.
All the other non-calculated items (all SNMPv3) are generated, but this one is NEVER generated.
The formula is a stripped down version. Actually I need to calculate the percentage of bandwidth utilisation, but since even the simpler formula doesn't work I stripped it down.

How can I know why the item is being ignored? Is there a way to debug the missed generation?

The version that I'm using is 4.0.0-1.1beta1.

Thanks.

[tamas-p]

I might be no the best person to answer, as I'm also just learning the bits of zabbix, but seems the item reference you use, is not correct. (For me the square brackets [] cause confuse, as I never seen to use them like that)
If is a template, it should look like something like this:

100-last(nodePerCpuIdleCore[{#SNMPINDEX}])

This one is one of my working calculation, where I can only query cpu idle % via snmp discovery, so I have to calculate the "usage"...
Obviously the actual item where the query happen has the key nodePerCpuIdleCore[{#SNMPINDEX}]

Or seen other way I have seen, where {template:key} where template is literal including spaces or what ever used in the name of the template.

I hope this helps..

[Onizuca]

Hi,
You can't use this formula.
Formula must looks like:
delta("ifHCInOctets.{#SNMPINDEX}]",15m)/900
Even if this formula will work it would not calculate bandwidth utilisation.
To calculate bandwidth utilisation you need to add one more element snmp "ifspeed".
The formula must looks like:
last("ifHCInOctets.{#SNMPINDEX}]")/last("ifspeed.{#SNMPINDEX}]")*100
Answer will be in %
Tell me if formula works.
Good luck.

[tamas-p]

Hi,
You can't use this formula.
Formula must looks like:
delta("ifHCInOctets.{#SNMPINDEX}]",15m)/900
Even if this formula will work it would not calculate bandwidth utilisation.
To calculate bandwidth utilisation you need to add one more element snmp "ifspeed".
The formula must looks like:
last("ifHCInOctets.{#SNMPINDEX}]")/last("ifspeed.{#SNMPINDEX}]")*100
Answer will be in %
Tell me if formula works.
Good luck.

Just to point out the there are closing ] but there are no openings at all.

[Onizuca]

Yes, you right, tamas-p. "]" not needed.
And i forget that better use "ifHighSpeed" if you have 1Gbps and more links.
Also don't forget that item ifHCInOctets.{#SNMPINDEX} must have preprocessing: "change per second" and "Custom multiplier=8". Maybe only this you asking for. To show speed in Mbps on interface... And you don't even need calculated item.
Like this:

But calculated item that i proposed will show used bandwidth in %. For example. We have 10Gbps interface. 5Gbps is 50% of total bandwidth. Its needed if wont to use trigger that alert you if interface if overloaded.

[nicodvb]

Hello,
thanks everybody for helping.
Unfortunately the item is still NOT being generated.
I've tried all possible variants of

delta("net.if.in[ifHCInOctets.{#SNMPINDEX}]",15m)/900
delta(net.if.in[ifHCInOctets.{#SNMPINDEX}],15m)/900
delta("ifHCInOctets.{#SNMPINDEX}",15m)/900
delta(ifHCInOctets.{#SNMPINDEX},15m)/900

but the item is still not there. Is there a way to run a command-line scan and see the discovery rule in action?
I also made sure to add to the preprocessing the filters

change_per_second and custom_multiplier: 8

Onizuca: I know that the formulas above don;t give the percentage of bw used, but I'm just trying to understand why the item is not being generated.

The formula that I'd use is:
100*
(
delta("net.if.in[ifHCInOctets.{#SNMPINDEX}]",15m)/900
/
(last(net.if.speed[ifHighSpeed.{#SNMPINDEX}]) * 125000)
)

ifHIghSpeed is expressed in 10Mbps units, hence it has to be multiplied by 1000000 and divided by 8




I'm afraid that your formula is incorrect:
last("ifHCInOctets.{#SNMPINDEX}]")/last("ifspeed.{#SNMPINDEX}]")*100

ifHCInOctets is just a counter that adds and adds over time to finally wrap around. It doesn't say how many bytes have passed between t1 and t2, unless you do a difference (that is the reason wht I used delta()).

[tamas-p]

Hi,

Ok, sorry I did miss the basic point of the question.
One reason could be if there are multiple items you want to create, the name of an item prototype, and key too, has to have some sort of variable in it based on the discovery it belong too..
A mistake I have made before, was similar. It complained can not create items as key and/or name already exist.. so a key would look like
key_name[{#SNMPINDEX}]
and name like
Named item {#SNMPINDEX}
As far as understand it would not work without this if there are more than 1 item needs to be created by the prototype...

[nicodvb]

Oh, finally the item is being generated!
As Tamas said I had to use the syntax
key: input_bw_pct2[{#SNMPINDEX}]
and the same for the name.
So finally now I should be able to fix the formula and graph the items.

I'll keep you updated.
Thanks