Creating a service template from the generic check_snmp_operation plugin

Context

Let's take the example of putting an Exagrid appliance under supervision.
After analyzing the MIB, the disk space used is obtained by performing operations between values from different OIDs.

This documentation is based on the ExaGrid case and can be used for any other checkpoint.

Steps to follow when placing a client under supervision

MIB analysis

According to the MIB of the equipment, there are two storage spaces. The values are expressed in MB. We will deal with the first space.
In addition to the percentage used, we want the space used in GB.

• % space 1 used : (Space1Configured - Space1Available) / Space1Configured * 100
• space1used in GB : (Space1Configured - Space1Available) / 1024

With DIOs :

• % space 1 used : (.1.3.6.1.4.1.14941.4.1.1 - .1.3.6.1.4.1.14941.4.1.3) / .1.3.6.1.4.1.14941.4.1.1 * 100
• space 1 used in GB : (.1.3.6.1.4.1.14941.4.1.1 - .1.3.6.1.4.1.14941.4.1.3) /1024

Creating the Exagrid-Space-1 service model

Navigate to "Configuration", "Services", "Templates" then "Add".

Enter the name of the service model.
The categories will be useful for the generation of reports. Here we supervise a disk space.
Thanks to this generic plugin we could monitor RAM, CPU, flow, temperature, etc...

We need to perform 2 operations (one for the percentage and one for the value in GB) between values returned by OIDs but also with integers.

You need:

• Enter the OIDs used in the calculation, separated by semicolons. The first OID will be OID1, the second will be OID2, the n-th will be OIDn.

• Write the two operations to be performed separated by the symbol Pipe |
  • If it is not necessary to carry out two operations, then no second formula is entered.
  • You can write a formula like OID1|OID2, here no calculation, the plugin just returns the 2 raw values obtained from the OID.
  • Only the result of the first operation is compared with the thresholds.

• Positioning of alert thresholds

• Enter the output format consisting of two parts separated by the symbol Pipe |
  • The first part is used to :
    • Define the text to be displayed
    • Choose the unit of the value from the first calculation
    • Choose the unit of the value from the second calculation (not required if no second calculation)
    • Here the output visible in the Technical Exploitation will be: "Used space : value1 % (value2 Go)".
  • The second part is used to define the names of the performance data generated by the plugin. Here two names, separated by a semicolon, because two values are calculated.
    Do not fill in this section if you do not want graphics.
    Giving a single name will create a graph for the value of the first calculation only.
    • The "used_prct" will be for the performance data of the first calculation.
    • The "used_Go" will be for the performance data of the second calculation.

Once the service model is created, it can be used in a checkpoint:

The 2 performance data are visible in the metrics:

To conclude

Improved version of the check_snmp_oidThe check_snmp_operation plugin brings a higher degree of intelligence to data processing.

Its customization, (display of raw values or up to 2 calculations, text output, units, creation or not of graphs, names of performance data) makes it a tool adaptable to any type of control.

This makes it very easy to create service models to supervise new equipment.