Discard broken item data

[thooge]

Hello,

i have some devices (thermometer) which are going sometimes to an
undefined state.
In this state i get a value of -999 which breaks my graphs badly.
Is there a possibility to filter out such values at data acquisition?

Kind Regards
Thomas

[batchenr]

what is the item key used ? can you post item conf ?

[thooge]

Here is my item data.
I think there is everything ok with zabbix.

The sensor sometimes sends an invalid value e.g. -999 or -999.9.
I want zabbix to ignore such values.

Perhaps it is a feature request: define a range of valid
values, e.g. -273 to infinite for temperatures in °C and
let the system throw away invalid values.

</item>
<item>
    <name>Sensor 1 Value</name>
    <type>4</type>
    <snmp_community>public</snmp_community>
    <multiplier>1</multiplier>
    <snmp_oid>.1.3.6.1.4.1.21796.4.1.3.1.5.1</snmp_oid>
    <key>hwgSensor1Value</key>
    <delay>100</delay>
    <history>120</history>
    <trends>730</trends>
    <status>0</status>
    <value_type>0</value_type>
    <allowed_hosts/>
    <units>°C</units>
    <delta>0</delta>
    <snmpv3_contextname/>
    <snmpv3_securityname/>
    <snmpv3_securitylevel>0</snmpv3_securitylevel>
    <snmpv3_authprotocol>0</snmpv3_authprotocol>
    <snmpv3_authpassphrase/>
    <snmpv3_privprotocol>0</snmpv3_privprotocol>
    <snmpv3_privpassphrase/>
    <formula>0.1</formula>
    <delay_flex/>
    <params/>
    <ipmi_sensor/>
    <data_type>0</data_type>
    <authtype>0</authtype>
    <username/>
    <password/>
    <publickey/>
    <privatekey/>
    <port>161</port>
    <description/>
    <inventory_link>0</inventory_link>
    <applications>
        <application>
            <name>Environment</name>
        </application>
    </applications>
    <valuemap/>
    <logtimefmt/>
</item>

[Semiadmin]

In this state i get a value of -999 which breaks my graphs badly.

Hi, thooge.
Just correct the graph - set "Y axis MIN value" fixed and equal to your minimal temperature value.

[thooge]

Your fix works for visualization.
But i don't want that value in the database.
E.g. it will be used for calculation on avg, trends etc. which
leads to wrong values.

[joseperes]

Hello,

i have some devices (thermometer) which are going sometimes to an
undefined state.
In this state i get a value of -999 which breaks my graphs badly.
Is there a possibility to filter out such values at data acquisition?

Kind Regards
Thomas

I have the same situation, did you find a solution ?

[Colttt]

If you use the latest version 4.2 yes its possible.
Here you can read this: https://www.zabbix.com/documentation.../whatsnew420?s[]=validation#validation_and_throttling_rules

[joseperes]

If you use the latest version 4.2 yes its possible.
Here you can read this: https://www.zabbix.com/documentation.../whatsnew420?s[]=validation#validation_and_throttling_rules

That's great news, unfortunately I Am in Zabbix 3.4 version and in my business they have no plans yet to upgrade the version. Is there another solution for this ?

[Semiadmin]

In 3.4 you may use preprocessing with regexp.
To replace -999 with 0:
(-.*)|([\d.]*) 0\2
To discard -999 would be better to create a dependent item with preprocessing:
([\d.]*) \1
In case of value -999 this dependent item becomes unsupported, but unlike master item unsupported dependent item doesn't require refresh interval for restoration.

[joseperes]

In 3.4 you may use preprocessing with regexp.
To replace -999 with 0:
(-.*)|([\d.]*) 0\2
To discard -999 would be better to create a dependent item with preprocessing:
([\d.]*) \1
In case of value -999 this dependent item becomes unsupported, but unlike master item unsupported dependent item doesn't require refresh interval for restoration.

Hey thanks a lot! thats what I was looking for ! Using preprocessing with regex, how can I tell to discard values below -10C and above +40C ?

[Semiadmin]

Maybe, something like this one:
^(-[\d]\..*)|^(-[\d])$|(^[1-3]\d\..*)|(^[1-3]\d)0$|(^[\d]\..*)|(^[\d])$|^(-10)$|^(40)$
\1\2\3\4\5\6\7\8

[joseperes]

Hi there, I am using this regex to get only values in the range 0 to 9999

^([0-9]|[1-8][0-9]|9[0-9]|[1-8][0-9]{2}|9[0-8][0-9]|99[0-9]|[1-8][0-9]{3}|9[0-8][0-9]{2}|99[0-8][0-9]|999[0-9]|1000)$                   \1

It's works fine but discards the value, I want to transform the value discarted in 0, how can I do that?

[Semiadmin]

Hi there, I am using this regex to get only values in the range 0 to 9999

^([0-9]|[1-8][0-9]|9[0-9]|[1-8][0-9]{2}|9[0-8][0-9]|99[0-9]|[1-8][0-9]{3}|9[0-8][0-9]{2}|99[0-8][0-9]|999[0-9]|1000)$ \1

It's works fine but discards the value, I want to transform the value discarted in 0, how can I do that?

 
 ^([0-9]|[1-8][0-9]|9[0-9]|[1-8][0-9]{2}|9[0-8][0-9]|99[0-9]|[1-8][0-9]{3}|9[0-8][0-9]{2}|99[0-8][0-9]|999[0-9]|1000)$|.*                    0\1

[joseperes]

Thank you ! It worked

[joseperes]

I have another situation that I need to get values in the range 0 to 100 and if the value goes above 100 should stay on 100. How can I do it ?

[Semiadmin]

I have another situation that I need to get values in the range 0 to 100 and if the value goes above 100 should stay on 100. How can I do it ?

For example:

(^(\d){1,2}$)|.*                                    -\1-100
-(\d+)                                                \1

[joseperes]

This is only working for the range 0 to 99 ...

[joseperes]

I got working the range 0 to 100 with this regex: ^(100|[1-9]?[0-9])$ \1

Now I just need to transform on 100 when the number is over 100. How can I do it ?