Beta SNMP Devices

Introduction and presentation

The monitoring of network elements is at the heart of supervision activities. This is why we have decided to develop a new monitoring engine based on the SNMP protocol.

More in line with your expectations, the main objective of this new functionality is to allow you to monitor your SNMP equipment simply and efficiently.

Contents

Creating an SNMP Device

Configuring an SNMP Device

Creating a widget

Adding an OID

The OID selector

The transform expressions

Example of expressions for the transformer

Adding an alert

Handling widgets

Importing widgets

FAQ

Prerequisites

Before using SNMP Devices, it is preferable to have some knowledge of how SNMP works, in particular:

- OIDs: An "OID" for "Object identifier" is the unique identifier of a value presented by a device via the SNMP protocol

- MIB: A "MIB" for "Management Information Base" is a set of information that allows OIDs to be described, in order to give more details on their values (description, type, formats, etc.).

Limitations

• During the beta phase, some bugs may still be present
• Widget display limited to 10 items per widget
• Interrogators must be Windows server agents

Creation and configuration of an SNMP Device

Creating an SNMP Device agent

To start using SNMP Devices, you must first create an SNMP Device Agent. There are two ways to do this, from the Tree View or from the Network Neighbourhood.

From the tree view, right click on a node, then "New SNMP device" to create the new agent. You can then name it.

From the network neighbourhood of a server agent, a "Create SNMP Device" button is available. By this way, the main parameters will be pre-filled.

Tip: To find your SNMP devices more easily, you can filter the "Windows detected" column to "No".

Configuring an SNMP Device

Once your SNMP Device Agent is created, select it from the tree to start the configuration.

Device configuration can be accessed via the "Configure" button in the centre of the screen (when the device is not configured), or via the configuration icon at the top right of the page.

The configuration will proceed through the following steps:

• The choice of the SNMP version, according to your Device. This will be "v2c" in most cases.
• The IP address of the equipment to be monitored.
• The port, to be modified only if you have changed the SNMP listening port on your device.
• The community, which will allow you to authenticate on the equipment, it must be identical to the one of the equipment to monitor.
• The choice of the polling agent, which is a server agent in your tree structure that must be on the same LAN as the equipment to be monitored. It is this agent that will act as a relay between the RG servers and your equipment. Make sure that this server agent is always online.
• Importing widgets, to save you time, it is also possible to import widgets from an existing SNMP device, if it is similar to the one you are configuring.
• OID scan, you can choose to run the scan which will inventory the OIDs of the device automatically after its creation.

Tip: In case you are importing widgets from another device, you can uncheck the OID scan box, as the OIDs to be monitored will already be known.

Once you have clicked on "Save", the OID scan will start (if you have left the box checked), it usually lasts a few minutes, the time it takes to make an inventory of all available OIDs.

If you have imported widgets without running a scan, your widgets will start displaying values after 5 minutes maximum.

During the scan, the following status will be visible in the top box of the page:

At the end of the scan, you should find the status that indicates that the scan is complete, specifying the number of OIDs found:

The Device is now ready for widget creation.

Creating a widget

Adding an OID

The widget creation screen looks like this:

It consists of 4 parts:

- The tabs (yellow box), which correspond to the values of your widget (1 tab = 1 value displayed in the widget).

- The OID selector, on the left (blue box).

- The transformer, in the centre (red box).

- The value obtained, on the right (green box).

The OID selector

The left-hand side allows you to select the OID to be monitored and to customise its name.

To select an OID, two possibilities:

• Type or paste the OID directly into the field provided.
• Open the OID selector via the "explore" button:   and browse the tree of OIDs of the equipment.

Clicking on the "explore" button opens the OID selector. It lists all the OIDs found during the equipment scan.

• The left-hand side shows the list of OIDs
  
  • Good to know: The OIDs listed are ranked according to their usage by RG users, the more an OID is used, the more it will be highlighted in the selector.
• The middle section displays the navigable tree structure of OIDs
• The right hand side displays the monitorable values of a parent OID selected in the tree

Once the OID to be monitored is found, simply click on "Monitor" to add it to the widget. "Monitor All" will take into account the first 50 child values of the OID.

Transformations expressions

This step is optional (except with OID combinations).

Once you have selected your OID(s), it is possible to apply a treatment to it. For example:

• Because some OID values are sometimes not very meaningful and difficult to use as they are.
• To use the functions of the transformer, in particular to calculate a bandwidth from a network interface OID of a switch, router, etc.

The transformer will therefore allow you to write expressions to manipulate and format the OID values.

• Good to know: To be processed with the transform expressions, the data must be received without unit. The unit will then be chosen via the drop-down list provided for this purpose.

In order to process the value of your OID in the transformer, you need to use the value() function.

value() (an alias of value(0) ) is a function that allows you to use the OID value to apply a transformation to it.

In the case where several OIDs have been selected, the corresponding values are accessible via the value(N) variables, where N is the index of the OID indicated in the list.

A "Paste into Transformation Expression" button allows you to automatically paste the correct variable into the expression input field.

Advanced functions are also available to allow or facilitate certain operations:

• previousValue() returns the previously evaluated value.
• growth() returns the difference between the last two evaluated values (equivalent to value() - previousValue() ).
• elapsed() returns the time (in seconds) between the last two evaluations.
• bandwidth() returns the bandwidth calculation (equivalent to growth() / elapsed() ), inferring that the associated OID is for a data volume (the basic unit is kept).

Example of expressions for the transformer

In the example below, a switch returns a value of "1", "2" or "3" to report the status of its power supply. The objective is to transform these numerical values into understandable text

value() == 1 ? "OK" : 
(value() == 2 ? "Warning" : 
(value() == 3 ? "Failed"))

Calculating a bandwidth

bandwidth()

Using combined OID's

(value(0) * value(1)) / value(2)

Other examples:

(value() * 100) / 255

value() * 8

Please see the context-sensitive help for more information on transformer expressions.

Output value

Finally, concerning the treatment of the data, it is possible to assign a unit to it, via the drop-down list located on the right-hand side:

As soon as a unit is selected, RG will automatically display the value with the most suitable unit (Kio, Mio, Gio... Year, month, week...).

Adding an alert

The step that follows the selection of the values to be monitored is the (optional) configuration of alerts on these same values.

The configuration of alerts will allow you to define :

• The conditions and parameters for opening the ticket, framed in blue
• The conditions and threshold for triggering the alert, framed in red in the image below

The "expression" text field is used in the same way as the field in the previous step. Help is also available by clicking on "How to write my expression".

To make it easier for you to write expressions, two "paste" buttons are available on the right-hand side of the interface, under "Monitored OIDs". They allow you to directly insert the aliases of the monitored values without having to type them.

Once your alerts have been added, the last step is a summary page on which you can name your widget and choose whether or not to activate the "curves" which will allow you to find your data in the form of graphs in the "Data" menu of RG.

Handling widgets

After these few steps, you will find your widgets on your Dashboard. Below is an example of a complete Dashboard, for monitoring a switch:

• Values in black: No alert is configured on this value
• Values in green: An alert is configured on this value, but the threshold is not reached
• Values in red: An alert is set to this value and the threshold is reached

Widgets are resizable and movable like this:

Icons are displayed in the Widget headers, they allow you (from left to right) to:

Import widgets

To facilitate the commissioning of environments with similar devices, you can import widgets directly from another device.

From the Pedigree page of your SNMP Device, the following button is available next to the "Add widget" button: It allows you to open the import window.

You will then have to choose between overwriting existing widgets, or adding widgets to the existing configuration, then choose the device from which to import.

After validation, the widgets will be available on your Dashboard, even if the OID scan has not been performed on this device. de votre Device SNMP, le bouton suivant est disponible à coté du bouton

FAQ