Monitoring

This section is designed to set up a check, results of which are displayed on the object or link.

The number of fields shown depends on the probe type. All built-in probe types and their settings are described in detail in the Built-in probes section.

Monitoring process starts after you press the Apply button. You can also perform the check on demand by pressing the Poll now button.

You can also test the check with the Test button. The system will perform the check and show the result in test window:

Test result window

You can use the polling on demand and testing functions only with SAYMON Agent starting with version 5.3.1.

Description of the most common fields:

Field Description

Agent

The name of an agent, registered in the system, with its ID and path to it in the hierarchy.

By default the system attempts to find the nearest agent to the object in hierarchy.

By clicking the button detailed information about the selected SAYMON Agent can be gotten.

Probe type

Selection of the probe type that is used in the monitoring process. There are built-in and custom probe types.

Timeout

Time period, during which the agent waits for check completion from the moment of its execution.

By default, timeout is 30 seconds.

If the check is not completed within this period, the state of the object changes to ALARM with the corresponding error, for example Sensor error!, Ping exited with error, exit code: 1.

Timeout works incorrectly with Program/script execution probes. If the script execution takes longer than the specified timeout, the object changes its state to WORKING and the probe returns the following data:

Period

Time period between checks. Starts from the moment when the previous check is completed. For each check a default value is displayed, which is used unless the user sets a value manually. The default value differs for different checks.

Below is an example of monitoring setup with the Ping probe:

Custom probes

SAYMON supports custom monitoring probes. These probes are shown in the "Probe Type" dropdown menu together with built-in probes. You can differentiate them by the icon – custom probes don’t have one.

When you select a custom probe, the system will show all arguments specified in the custom probe’s configuration file as well as the "Timeout" field.

Default timeout value is 30 seconds.

Variables

Sensor configuration fields support using property values as variables.

This functionality is not available for links.

Sensor fields use the following template format for property values:

{{parent[`parent name`|class.(name|id)=`name|id`].properties[`name`][`valueIndex`]}}

In this format, only {{properties[name]}} is required.

For example, to use a host address of the Ping sensor from the host property of the same object, you can set the sensor the following way:

You can also use the Set Object’s Monitoring Properties request with the following request body:

[
    {"name":"TaskDictionary"},
    {"name":"AgentId","value":"62fad334ac60e1490083e044"},
    {"name":"TaskPeriodValue","value":"1"},
    {"name":"TaskPeriodUnit","value":"seconds"},
    {"name":"TaskType","value":"ping"},
    {"name":"PingHost","value":"{{properties[host]}}"},
    {"name":"PingPacketsCount","value":"4"},
    {"name":"PingTimeout","value": "0"},
    {"name":"PingSrcInterface","destroy":true}
]

You can find example of using variables in the script body on the Use property values in script body page.

If the sensor fields uses variable template, the system will show the button next to it. This button will show the current value of the used property. You can also check the current property value by hovering over the variable. The value will be shown in the tooltip.

When you try to delete a property or edit its name, the system checks whether other properties or fields depend on its name or value. If such dependency is found, the system will prevent you from deleting a property or editing its name and display an error Consistency error: Property is used as a variable in one or more entities.

System will automatically update parameters in the following cases:

value of the property used as a variable changed;
dictionary used in the property changed;
object’s parent changed.

Field Value Substitution

You can substitute values certain check fields with other check fields using the format {{field-id}}.

This is primarily used to pass data from the account dictionary to other fields (for example, in script descriptions).

Experimental functions

To enable this functionality set the experimental parameter in the web application configuration file.

Stat Operators fields allows you to set stat operations that the system will use to pre-process data received from selected monitoring probe.

SSH Script Execution probe can execute a script on the target system with elevated privileges. If experimental features are enabled, you can specify login and password of a sudo user.

Select login and password from a dictionary

Some sensors can retrieve authentication information from the system dictionary "Connection credentials."

To add a new account, you need to add a new entry to the "Connection credentials" monitoring dictionary in the System group.

You can find out more in the corresponding section of this documentation.

For the SNMP Get sensor, there is a special system dictionary called "SNMP connection credentials". In this dictionary, you can set the communityRead field to fill in the Community field.