# 1 Configuring a trigger

#### Overview

To configure a trigger, do the following:

-   Go to: *Configuration* → *Hosts*
-   Click on *Triggers* in the row of the host
-   Click on *Create trigger* to the right (or on the trigger name to
    edit an existing trigger)
-   Enter parameters of the trigger in the form

#### Configuration

The **Trigger** tab contains all the essential trigger attributes.

![](../../../../assets/en/manual/config/triggers/1.9.9_trigger.png){width="525"}

|Parameter|Description|
|---------|-----------|
|*Name*|Trigger name. The name may contain macros.<br>**$1, $2...$9** macros can be used to refer to the first, second...ninth constant of the expression.<br>*Note*: $1-$9 macros will resolve correctly if referring to constants in relatively simple, straightforward expressions. For example, the name "Processor load above $1 on {HOST.NAME}" will automatically change to "Processor load above 5 on New host" if the expression is {New host:system.cpu.load\[percpu,avg1\].last(0)}>5|
|*Expression*|Logical [expression](expression) used for calculating the trigger state.|
|*Multiple PROBLEM events generation*|By checking this option you can set that an event is generated upon *every* 'Problem' evaluation of the trigger.|
|*Comments*|Text field used to provide more information about this trigger. May contain instructions for fixing specific problem, contact detail of responsible staff, etc.|
|*URL*|If not empty, the URL entered here is available as a link when clicking on the trigger name in *Monitoring → Triggers*.<br>One macro may be used in the trigger URL field - {TRIGGER.ID}.|
|*Severity*|Set the required trigger [severity](severity) by clicking the buttons.|
|*Enabled*|Unchecking this box will disable the trigger if required.|

The **Dependencies** tab contains all the [dependencies](dependencies)
of the trigger.

Click on *Add* to add a new dependency.

::: noteclassic
You can also configure a trigger by opening an existing one,
pressing the *Clone* button and then saving under a different
name.
:::