It's possible to get historical value in trigger name?

[Freezstyler]

Hello,
I'm building a trigger for changing an RSSI value in our antenas. Typical use case will be after heavy snowing or strong wind.

I would like to see somehing like: {HOST.NAME} RSSI changed from OLD.VALUE to CURRENT.VALUE, so I would like to get historical value, print it and the same I need to do for actual (last) value.

I didn't find any useful macro here: https://www.zabbix.com/documentation...ed_by_location but maybe it exists some workarounds.

I can get a host name and item current (last value) now I need just old (historical value).

For now I have this:

{HOST.NAME} RSSI changed from to {ITEM.LASTVALUE}

On this printscreen I have used {ITEM.LASTVALUE} and {ITEM.VALUE} but I got same value.



and expression like this: change(/Siklu_CB1/siklu.rssi)<10 (here I want to ask, the RSSI is a negative value and for example -35 is better than -40, how should I treat to negative values in terms of expressions?)

Thank you!

[Freezstyler]

Nobody know please?

[Semiadmin]

{?EXPRESSION}

[Freezstyler]

Hmm, can someone point me to right direction? I tried to use last(/Siklu_CB1/siklu.rssi) <> last(/Siklu_CB1/siklu.rssi,#20) but it still prints same values. And I need to trigger this only if the value changes for example by 10dbm

I tried also this: last(/Siklu_CB1/siklu.rssi) <> last(/Siklu_CB1/siklu.rssi,#20) and change(/Siklu_CB1/siklu.rssi)<>10 but this one also don't work.

Long story short, I need two things.

1) Get values for last RSSI and previous and if the change is more than 10db than fire the trigger.
2 Print the values last and previous in trigger name.

Thanks.

[Freezstyler]

I tried different approach. I'm almost there, but I have somewhere an error. The {ITEM.LASTVALUE1} and {ITEM.VALUE2} always gets the same value, but it should take value from history of 1 day ago

[Markku]

Semiadmin said it already, I'll add the link to documentation: https://www.zabbix.com/documentation...ression_macros

Markku

[Freezstyler]

I found this part of documentation, but unfortunately Zabbix documentation is one of the worse I have seen so far. It lacks enough of images with examples.

I would not bother anyone if I didn't spend like two days on this simple task.

So please, is my expression right? I think I need to add an "and change()" and there specify that 10dbm?

And i don't understand where to put "?" In the expression or trigger name?

Thank you kindly.

[Markku]

Ok now I haven't ever used it, but by reading the documentation and looking at the examples there:

{?last(/Siklu_CB1/siklu.rssi)} should give you the last value of that key, and

{?last(/Siklu_CB1/siklu.rssi,#2)} should give you the previous value.

They are used in the trigger event name.

Markku

[Freezstyler]

Thank you and for 1 day old value can i use it like this, or there is better approach?

{?first(/Siklu_CB1/siklu.rssi,1d)}

[Markku]

That should do it, yes

Markku

[Freezstyler]

I tried it today, but it's not working, I got *UNKNOWN* *UNKNOWN* instead of values. Screens with configuration below :/

[Markku]

The documentation says that the expresssion macros are available (f.ex.) in "trigger event names", not in trigger names.

Markku

[Freezstyler]

Ok, I moved the macro to "Event name" and still got *UNKNOWN* *UNKNOWN*

[Markku]

Works here:





Zabbix 6.2.4

Markku

[Freezstyler]

I have 6.2.2 version of Zabbix, but I don't think that version is the problem?