SNMP Devices Management

Find out how to discover and monitor SNMP devices such as printers, routers, switches and VMWare.

Updated over a week ago

Introduction

In this guide, we will show you how to discover and monitor SNMP Devices.

You can use the Naverisk Probe to discover Devices, allowing you to monitor your client’s Printers, Routers, Switches, VMWare and other SNMP enabled Devices quickly and easily. Naverisk also offers the ability to manually create SNMP Traps if required.

1.0 Prerequisites

In this chapter we will cover all the necessary changes that need to be made to your Devices before configuring SNMP Monitoring within Naverisk.

1.1 Setting up your SNMP Device

Naverisk uses SNMP Get to find Devices to monitor within the IP range that you set (this is covered under 2.1 Setting Up a Monitored SNMP Device). For the SNMP Devices themselves, ensure that;

  1. The SNMP Device is online and SNMP is enabled.

  2. This SNMP Device either has a community string such as 192.168.99.75@162/public or the SNMP device has been set with a Username and Password as these will be needed for Naverisk to complete a successful scan.

1.2 Installing the Naverisk Probe

To ensure that the Naverisk Probe can discover Devices correctly, upload the following Script Pack to your Naverisk Instance and run this script against the Device that you will install the Naverisk Probe on;

This script pack is intended to install a Visual C++ redistributable required for the functionality of the Probe / SNMP package.

The Naverisk Probe can be installed on any Microsoft Windows Device on the Network, which the SNMP Devices such as VMWare can connect to. The Host Device (Probe) should always be on. When it is offline you will not get any Alerts raised or Tickets created for your SNMP Devices.

To install the Probe module, you will need to choose a Host Device to have the Probe package installed on.

  1. In the Devices tab, select the Host Device that you will install the Probe package on, under the client you wish to monitor.

  2. From the Device Tasks dropdown select Manage Packages:

3. Under the Available Packages drop-down, select the Probe and click install:

4. Once the Package is installed you will receive a new tab called Probe;

Once you have this place, you should now be ready to start adding SNMP devices for monitoring.

2.0 How to Setup SNMP Monitoring

2.1 Setting up a Monitored SNMP Device

  1. To add SNMP Device into Naverisk, navigate to the Devices Tab, click on 'New Device' and select 'Create New SNMP Device'.

2. You will now be prompted to select a Probe; this will be the Host Device that was set up under section 1.2

3. Under the ‘Probe Settings’ Click on the ‘Add’ button and enter the Probe Type, Start IP, End IP, Community String or name, Authentication and Description as needed. Please be aware that the Community String is case sensitive, and needs to match your devices configuration exactly.

4. Once you have saved the Probe Information, click on the 'Retrieve Information' button to run the scan, and then select your Devices that you wish to manage. They will be listed under Discovered SNMP Devices or Discovered WMI Devices:

Note: for more information on WMI Devices, refer to the Agent Deployment Guide.

We have now completed telling this Probe that it is responsible for monitoring our SNMP Devices. Naverisk offers Out of the Box Monitoring that is loaded automatically once an SNMP Device is discovered.

Should the Probe not find any SNMP Devices, please ensure that these Devices have the ability to be monitored via SNMP and are SNMP enabled. Please refer to Section 3.0

2.2 Managing SNMP Devices

  1. Now that the SNMP Devices have been added to the Managed SNMP Devices list, simply click on the Devices' name to bring up the Devices; details page.

2. In the Devices' details page, click on the Monitoring tab, select desired Alert and OS Templates. OS Templates come pre-configured for VMWare and are loaded automatically.

3. You can create a device specific template which allows you to monitor CPU and send a ticket if disconnects. Adjust wait time to suit and make sure you click save settings before exiting page to apply change.

2.3 SNMP Templates

Naverisk has OS Templates that are setup with SNMP printer values. You can clone these templates to be exported/imported as preferred.

You can only edit these templates once you have assigned them under a SNMP device's monitoring tab.

Creating a new SNMP OS template to use on other devices is a quick and simple procedure. Once you have your initial SNMP device configured the way you would like it, simply scroll up to the 'Device Tasks' at the top right, and select 'Create OS template from Device':

Provide a suitable name for your template, an hit save:

And you will now have a new OS template that you can copy and/or export to move it around your system to apply it to other compatible devices:

2.4 Configuring SNMP Values

Naverisk can raise Alerts via SNMP Get. SNMP Get is used for Retrieving information about the state of specific Devices. In my example below, the OID, Name, Comparison, Value, SLA Class and SLA Status have been set so that a Ticket will be raised when a specific Printer’s cartridge has less than 30% Toner Ink left.

Simply add the OID that identifies the Printer’s Toner levels, OIDs can usually be found via the Manufacturers website or on 3rd party websites such as http://www.oidview.com/ 

OIDs are used to identify an object such as the cartridge of a printer or a Virtual Machine for monitoring purposes.

2.5 Configuring SNMP Tables

The purpose of the SNMP Table is to display what you can monitor (based in the OID) and allow you to choose what you want to monitor.

This Table will be automatically populated with all of the objects depending on the OID that you use. An OID has been entered that populates this Table with all of the Virtual Machines on a specific Host:

You can use this Table to monitor several different objects depending on the Rows or Columns that you choose. For example: The machine from Row 8 will raise an Availability Failure if the Comparison contains a "notRunning" value in column 7.

Note: You can replace the current table settings back to the default values if a mistake has been made in the ESX configuration.

3.0 Case Study - Monitoring ESX Virtual Machines

In this case study, a Monitored Table has been created to showcase the monitoring capabilities for ESX Virtual Machines that Naverisk can achieve with SNMP Get.

The objective is to have Naverisk create an Availability Failure Alert if the 2008SBSStd Virtual Machine stops running.

Firstly, make sure that vSphereCLI is downloaded and installed on a Management Device. Then use the commands to enable SNMP.

Commands are:

  1. vicfg-snmp.pl --server hostname --username username --password password -c com1

  2. vicfg-snmp.pl --server hostname --username username --password password -p 161

  3. vicfg-snmp.pl --server hostname --username username --password password --enable

Review the settings using:
Vicfg-snmp.pl pl --server hostname --username username --password password enable --show

  1. Sets the community string to com1.

  2. Sets the port to 161 which is the default.

  3. Enables the SNMP service.

OID: the ‘vmwVmEntry’ OID has been used to populate the table with all of my Virtual Machine Entries. This OID was sourced from http://www.oidview.com/mibs/6876/VMWARE-VMINFO-MIB.html 

Upon entering the vmwVmEntry OID, the Naverisk table has automatically populated with all of the Virtual Machines:

Key Column: This represents the Primary Key of the Table. The selected Column 1 as the 'Key Column' as this column has all of the Virtual Machines.

Key Value: This represents the Unique Value of the Key Column. Selected here are the 2008SBSStd Virtual machine from this list as this is the specific machine that Naverisk is required to monitor.

Data Column: The Data Column represents the trigger that Naverisk is required to monitor. Column 7 is selected as the Data Column as this shows the running state of the Devices.

Once the Comparison, Value SLA Class, SLA Status, Violation Duration (in seconds) and Clear Alerts Duration (in seconds) have been added, this Monitored Table is complete;

With the ability to create Monitored SNMP Traps, Values and Tables Naverisk can monitor any SNMP metric.

4.0 Utilising MIB Files

4.1 Configuring SNMP Traps

In order for an SNMP Trap to be able to send information from a monitored Device to Naverisk, you will need to import your MIB's before creating a new SNMP Trap. Use the Settings > SNMP screen to import the MIB’s you require. Make sure the MIB’s actually contain Trap information. Look for the TRAP-TYPE keyword to identify if Traps are defined.

Use the Import MIB button to import the Files and the Dependencies

Load these at the Top Level. They are not visible to sub-clients but can be seen and used when you are defining Traps.

Once the MIB's have been imported, navigate to Devices > Devices Details > Monitoring > New Trap.

  1. Ticket Group: This is a text field that should be the same for Tickets you would like to connect. This allows Events to close Tickets as well as open them.
    Check - Close All when you would like all Tickets in this group to be closed when this Event happens.

  2. SLA Class: This is the SLA class you would like to apply to this Ticket.

  3. SLA Status: This indicates the status of this Ticket.

  4. Reporting Status: This additional field is present to indicate what affect the incident has on reporting if the SLA class is Backup or Anti-Virus.

  5. Trap Version: This is either SNMP V1 or SNMP V2c. This indicates the format the SNMP Trap will be in when it arrives. SNMP V1 Traps have a Trap Type see below.

  6. Trap Type: For SNMP V1 there are several predefined Trap Types. Such as Cold Start, Warm Start, Link Up, Link Down. These can be selected here, or use Enterprise Specific to use the imported MIB.

  7. SNMP Definition: This will match the name defined by the MIB you imported. In our case we want to use VMWARE-VMINFO-MIB.Many MIB are there for dependencies and may not have Traps defined.

  8. SNMP Trap: This is the list of actual Traps defined in the MIB. In this case we are looking for the vmwVmPoweredOff Trap. We will use the vmwVmPoweredOn Trap to clear the Group.

Additionally, a Trap can have parameters that are completely defined by the manufacturers. Where they exist, you need to pull them out and specify what you want to match. Default - will match everything.

Match conditions are

  • () contains

  • = equals

  • < less than

  • > greater than

5.0 Troubleshooting

5.1 Windows Devices not Appearing after SNMP Scan

If you can’t find any devices with the SNMP Scan, this may be because a Windows update that the Naverisk Probe requires is missing, this may stop the SNMP Device retrieval or SNMP GET functions from working correctly.

If you encounter this problem, please upload the following Script Pack to your Naverisk Instance and run this script against the Device that has had the Naverisk Probe installed on it. http://docs.naverisk.com/Resources/NavFiles/SNMPVC++Fix.nsp 

This Script Pack will install a Microsoft security update that resolves the flaw. Visual C++ 2005 redistribution Service Pack 1 MFC Security update x86.

5.2 Changing Device IP

If you change the IP of the monitored device you will need to re-create the device. This is as the device is created using the IP as a reference. Failure to re-create will alert you with the device being offline.

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