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SNMP Device Self-Certification

Last update January 14, 2017

The SelfCert portlet is a tool that allows you to add new device and MIB OID support to only your instance of the SNMP Data Monitoring (snmpcollector) probe. Use the SelfCert portlet if existing device metrics are not sufficient, or you have an unsupported SNMP enabled device. Creating a custom vendor certification for a device replaces all the existing metric definitions with a new set.


Revision History

This table describes the history of updates to the SelfCert portlet.

Version Description State Date

What's New:

Changed the following fields in the GUI and documentation:

Former Field Title Current Field Title


User Username
Security Security Type
Method Auth Protocol
Password Auth Key
Priv.Password Priv Key
Priv.Protocol Priv Protocol

Fixed Defects:

  • Fixed a defect in which, when the user clicked Test Credentials for SNMPv3, the test failed for valid credentials.
GA June 2016
  • Added the ability to deploy a custom vendor certification on multiple snmpcollector systems.
GA February 2016
  • Added the ability to define custom OIDs.
  • Added error checking when loading MIB files into the MIB File Manager.
GA November 2015
  • Corrected an issue where MIB files were not loaded correctly in a vendor certification.
  • Vendor certifications that are created with earlier versions of the SelfCert portlet now work in version 1.1x.
GA October 2015
  • Added an improved MIB file manager for adding and removing vendor MIB files. The MIB file manager has access to a repository that contains copies of the MIB files that are shipped with the snmpcollector probe. You can also add new MIB files to this repository.
  • The MIB File Manager repository now includes over 750 MIB files.
  • Added search functionality to the MIB Tree and Metric Families list.
  • Added I18n support for different languages.
  • The portlet now saves your work throughout the self-certification process. Vendor certification information is not lost if you close your browser window or your browser session expires.
GA September 2015
1.01 Updated list of supported functions GA June 2015
1.0 Initial Release GA March 2015

Quick Start Video

Click to view the SNMP Device Self-Certification Overview video.

Supported Features

The SelfCert portlet allows you to:

  • Add new OIDs to a vendor certification
  • Associate OIDs with existing metrics
  • Create or modify custom vendor certifications 
  • Create expressions
  • Modify existing expressions

Association of Metrics with Devices

The expressions define the metric measurements that you view in USM. The snmpcollector probe associates specific metrics with a device through the use of metric families and vendor certification files.  

Metric Families

A device is subdivided into components by snmpcollector. A component can represent physical components such as CPUs or memory, or logical components such as interface jitter or HTTP response. A single metric family defines each component. Metric Families organize all the metrics that might be valid for a particular type component. Each metric family is a comprehensive catalog of related metrics.

Usually, a particular component vendor supports only a subset of the metrics in a metric family. For example, a metric family for CPUs contains the metrics cpuUserUtilization, cpuSystemUtilization, and cpuIdleUtilization. A CPU from a particular vendor might only support the cpuSystemUtilization and cpuIdleUtilization metrics.

The following diagram shows an example metric family.

Metric Family and Metrics

Vendor Certifications

A vendor certification is a library of metric definitions for a specific device from a specific vendor. A vendor certification file defines the specific mechanisms for monitoring the components of a specific device make and model. Many vendor certification files exist in snmpcollector. Each vendor certification file contains device specific:

  • Vendor OIDs - A vendor certification can contain a subset of the OIDs found in the original vendor MIBs.
  • Variables - Variables represent the device OIDs for the target system.
  • Expressions - Expressions define the metrics that you view in USM by using variables or other data.

The following diagram shows how vendor certifications are associated with a metric family.

Vendor Certification Association with Metric Family


If a vendor certification file exists for a device, then the snmpcollector probe can collect metric data for the device. Each vendor certification file contains one or more device OIDs and expressions. Expressions generate the metric data that you can view in USM. The tool supports any valid expression that can contain:

  • Operators - The operations and numbers that are part of a calculation. Some expressions use OID data points in a calculation.
  • Variables - A variable represents an OID data point that is queried from the system.
  • Functions - A list of available programming functions is provided for use in the tool.

Note: The Java functions and operators in an expression are supported by MVEL. The MVEL Language Guide is available on the web.


The following functions are supported in the SelfCert portlet:

availabilityWithSysUptime(Long sysUpTime, Long duration)

This function calculates availability using sysUpTime and duration.    

convertSignedIntToUnsignedDecimal(Number signedVal)

This function takes a signed integer and converts it to an unsigned floating-point value of the next greater size.

convertSignedIntToUnsigned(Number signedVal)

This function takes a signed integer and converts it to an unsigned integer value of the next greater size.  

isdef(Object variable)

This function tests whether the variable is defined within the given scope.

nullIf(Object val, Object defaultVal)

This function detects and handles a null object. If val is null, return the defaultVal otherwise returns the val.  

nullZero(Object val)

This function detects and handles a null object. If the val is null, returns BigDecimal.ZERO otherwise returns the val.        

snmpConstArrayMap(Double value, Integer[] numbers)

This function maps one set of values to another set of variable values. This function truncates the input value to an integer if necessary. The function uses the integer value as an index to the set of constants that are shown as c0, c1, up to cn-1. The c values must be integers. This function checks these values when the expression is parsed and returns cx. If value is not in the domain from 0 to n-1 (inclusive), the result is 0 (without an error message).

snmpCounter64(Long hiVal, Long lowVal)

This function takes a high order and low order 32 bit unsigned (Long) value and converts to a 64 bit (BigInteger) value.

snmpGetUpSinceTime(Long uptime)

This function takes a high order and low order 32 bit unsigned (Long) value and converts it to a 64 bit (BigInteger) value. 

snmpProtectedDiv(Double val1, Double val2)

This function divides two double values and returns the result. If dividend is null/zero, return 0.

snmpRound(Double dNumber)

This function takes a numeric value and rounds its value to the nearest integer value.             

Verify Prerequisites

Verify that required software is installed before you install the SelfCert portlet.

  • CA Unified Infrastructure Management (CA UIM) 8.2 or later is installed
  • UMP 8.2 or later is installed
  • At least one installed instance of snmpcollector v2.1 or later
    • The probe must be installed on a remote hub. For more information, see the snmpcollector release notes.
    • The probe must be installed within the same domain as UMP. 

Install the SelfCert Portlet Package

The SelfCert portlet is not included in the default CA UIM installation. Download and deploy the package to your CA UIM system.

Follow these steps:

  1. Download the SelfCert portlet (ump_selfcert) package from the Support Archive.
  2. Go to the CA UIM Admin Console.
  3. Select Archive > Local Archive.
  4. Select Import and then select the file. 

    Note: Select Yes if you see a message about overwriting the package.

    A "Your package has been saved to the archive." message appears if the import is successful. The ump_selfcert package is in the Local Archive. 

  5. Drag the ump_selfcert package from the Local Archive to the UMP robot.

    Note: If you have multiple UMP robots, install the ump_selfcert package on a single instance.

  6. Click Distribution Activity and wait for the installation to complete. When the installation is complete, the "Installing ump_selfcert" status is green and has a stop time.
  7. Choose one of the following steps: 

    • If wasp is active, wait for wasp to restart. 
    • If wasp is deactivated, activate wasp now.

Configure the Portlet

Add the portlet to one of your pages in UMP.

Follow these steps:

  1. Enter the URL of your UMP installation in a browser.
  2. Go to either your public or private pages.
  3. Select the page to add the SelfCert portlet.

    Note: If you want to create a new page for the SelfCert portlet:

    1. Go to Add > Page.
    2. Name the new page.
    3. Click the green checkmark.
  4. Select Add > Portlet.

  5. Search for the application type SelfCert.

    Note:The Self-Certification Tool can also be found at Monitoring > SelfCert.

  6. Drag the SelfCert portlet to the page.

  7. Refresh the page and go to the portlet.

    Note: Clear your browser cache after you install or upgrade the Self-Certification Tool.

Load Device Data Into the Tool

The following figure shows the steps that you must complete before you can create a vendor certification file.

Process for Loading Device Data

Select an snmpcollector Instance

The discovery server locates systems that have an instance of the SNMP Data Monitoring (snmpcollector) probe. Select an snmpcollector instance before creating a vendor certification. Any vendor certification that you create is system-specific. Create a vendor certification for each snmpcollector instance you want to update.

Follow these steps:

  1. Go to the Quick Start page.
  2. Select the snmpcollector instance that you want to use as the deployment target for the vendor certification. All queries to the target device are run from this instance.

Identify the Target Device

The SelfCert portlet uses the credentials for the target device to run queries against the target device. You cannot go to the next page unless you enter valid credentials.

Follow these steps:

  1. Go to the Select Device page.
  2. Enter the appropriate authentication information for your device.
    Fields to know:
    • Device fields:
      • Host - The name or IP address of an SNMP enabled device.
      • SNMP Port - The SNMP port for the device or component. Port 161 is the default value for most devices.
      • Version - The supported SNMP version for the monitored device. Versions 1, 2c, and 3 are supported. When v3 is selected, other fields for security and privacy are required.
    • SNMP v1 or v2c:
      • Community - The SNMP community string. This string is sent across the network in clear text as part of SNMP v1 or v2c requests, which can pose a security risk.
    • SNMP v3 fields:
      • Username - SNMP v3 user name that is used to access the monitored device. Required for all SNMP v3 security levels.
      • Security Type - SNMP v3 security level of the user. Depending on what level of security is selected, other security fields are enabled or disabled:
        • NoAuthNoPriv - messages are sent unauthenticated and unencrypted
        • AuthNoPriv - messages are sent authenticated but unencrypted
        • AuthPriv – messages are sent authenticated and encrypted
      • Auth Protocol - SNMP v3 method of encryption, when the security setting is AuthNoPriv or AuthPriv. Options are:
        • MD5 - MD5 Message-Digest Algorithm (HMAC-MD5-96)
        • SHA - Secure Hash Algorithm (HMAC-SHA-96)
        • None
      • Auth Key - The password that is associated with the SNMP v1/v2c device or SNMP v3 user. This field is required if AuthNoPriv or AuthPriv is selected.
      • Priv Key - The SNMP v3 privacy password to use if the AuthPriv security level is selected. Do not confuse with the user password (authentication).
      • Priv Protocol - SNMP v3 privacy (encryption) protocol to use. Options are:
        • DES - Data Encryption Standard 
        • AES - Advanced Encryption Standard 
  3. Click Test Credentials.
    A success message appears if the SelfCert portlet can connect to the device.

(Optional) Load a New MIB

Use this procedure to load a new MIB file into the tool. The tool validates the contents of the file and displays any errors.

Follow these steps:

  1. Go to the Select Object ID page.

  2. Click MIB File Manager above the MIB Tree.

  3. Click Add MIBs and select one or more MIB files to add.
    The tool checks the file for errors and displays the current status of the file in the tool.

    Note: If the status is Error, click the magnifying glass to view more information.

  4. Select an action. Options are:
    • Add - Add the file.
    • Ignore - Do not add the file.
    • None - Do not select an action.
  5. Click Execute to perform the actions you selected for each MIB file.
    Any MIB files that you add, must be loaded into the MIB file manager to appear in the MIB Tree.

Identify Device MIBs

Select one or more tabular or scalar OIDs for your target device. You select MIBs with valid OIDs from the MIB tree. Use the MIB file manager to control the contents in the MIB Tree and to load your own MIB files into the tool repository. The repository contains the MIB files that are shipped with the snmpcollector probe and any new MIB files that are loaded by a user. 

Follow these steps:

  1. Go to the Select Object ID page.

  2. (Optional) Click MIB File Manager above the MIB Tree to add or remove MIB files. Add a MIB file to the repository before you can load and view the MIB file in the MIB Tree. For more information, see Load a New MIB File.

    Note: The Delete Selected MIBs and Restore Selected MIBs options are not available for all MIB files. You cannot delete any of the MIB files that are shipped with the snmpcollector probe, and you can only restore the MIB files that you overwrite.

  3. Select an OID in the MIB Tree. 
    The OID description appears in the right side of the page. In earlier versions of this tool, all this information is read only.
    Starting with version 1.12 you can enter the following information for an OID that you know exists for a device:
    • Object ID - The OID for a device. You do not need to load a MIB file that contains the OID.
    • Object ID (Qualified) - The text representation of the OID.
    • Type - The OID type. Options are:
      • Tabular - The OID contains multiple indexes.
      • Scalar - The OID contains an index of 0.
    • Syntax - The data for the OID.
  4. Select the SNMP operation that you want to run on the device to verify the OID.  
    The results of your operation appear in the table. The valid device OIDs generate a variable and a MIB ID.
  5. Select Add OID to Cart to add the OID to the vendor certification. 
    The Cart icon displays the number of selected OIDs.

    Note: To view a modifiable list of selected OIDs, click the Cart icon.

  6. Repeat this process until all required OIDs are in the Cart.

Customize a Vendor Certification

The following figure shows the steps that you must complete to create a custom vendor certification file.

Vendor Certification Customization Process

Select a Metric Family

Metric Families organize all the metrics that might be valid for a particular device component. The SNMP Device Support tool helps you identify the metric family that contains metrics for your device.

You can only make one vendor certification per metric family for a particular device. For example, you can only create one vendor certification for a Cisco-x router that is associated with the CPU metric family. If you must create another vendor certification for this device, choose a metric family other than CPU.

Follow these steps:

  1. Go to the Select Metric Family page. 
  2. Go to the SNMP Device Support tool to identify a metric family with metrics for your device.
  3. Enter an OID in the search field to view all the metric families that contain the OID.
    The SNMP Device Support Tool displays all the metric families that contain the OID, the vendor certification that is associated with the metric family, and the metrics that use the OID attribute.
  4. Determine which metric family contains the metric you need to modify.
  5. Return to the Select Metric Family page, and select the appropriate metric family. 
    The metric descriptions appear in the right side of the page. This information is read only.

Modify Expressions 

Expressions define the data that appears in USM as metrics. Use this procedure to modify the expression that is associated with a selected metric. Any expression that you modify is permanently associated with the metric you selected.

The original expression is lost if you modify an existing vendor certification file.

Follow these steps:

  1. Go to the Create Expression page.
  2. Select a metric in the Metrics list.
    The metric description appears at the top of the page.
    Fields to know:

    • Polled Metric - Indicates how data is collected for the metric.

      • If set to true, metric data is collected at set intervals.

      • If set to false, metric data is collected only once during device discovery.

    • Host - The target device name or IP address.

    • Metric Type - The format of the metric data. The results of your expression must match this format.

    • Units - The units for the data.

    • Rate - Options are true or false.

      • If true, the system automatically calculates the expression output as a rate per second. The metric expression output is divided by the number of seconds since the last time the metric was polled. For example, the bits metric for interfaces is set as a rate. The system takes whatever value the expression calculates for bits, and before delivering the metric, divides the value by the number of seconds since the last time the metric was polled. If 320 seconds have passed since the last time bits were polled, the system divides the new measurement by 320 before publishing the metric.

      • If false, the tool does not modify the expression output.

  3. Click Create Expression.
    The expression modification window opens.

  4. Use the number pad, Variable list, or Functions list to create or modify an expression. Place your cursor in the text box to add items to different locations in the expression.

  5. Click Ok.

  6. Click Test to view the expression data. Make any required changes if necessary. You cannot deploy a vendor certification file with an invalid expression.

  7. Repeat this process for every metric you want to modify.
  8. Verify that you have modified the Names metric. For every metric family you modify, select and modify the Names metric. Assign one of the following expressions to the Names metric:
    • A string value in a pair of double quotes. For example, "component name".
    • An OID value. For example, ifDescr.
    • A combination of string values and OIDs. For example, "Name" + ifDescr.

Manage Custom Vendor Certifications

Use the SelfCert portlet to add or remove your custom vendor certification files on a specific snmpcollector server. 

Note: You cannot deploy a single vendor certification file on multiple snmpcollector servers. Create a vendor certification file for each snmpcollector server. 

Follow these steps:

  1. Go to the Deploy Certification page.
  2. Select one or more snmpcollector instances.
  3. Enter a name for the vendor certification.
  4. Click Save.
    The vendor certification is deployed to your selected snmpcollector instance. The snmpcollector probe rediscovers all devices that are relevant to the vendor certification.
  5. Go to the snmpcollector probe configuration GUI and rerun discovery to activate the vendor certification.


Why is the SelfCert portlet not working correctly after an upgrade?

Some artifacts from the previous version of the tool remain in your browser cache. Always clear your browser cache after you upgrade the tool. 

Where can I find more information about MVEL?

The MVEL Language Guide is available on the web.

How do I know if my custom vendor certification is deployed?

Follow these steps:

  1. Open the snmpcollector probe configuration GUI.
  2. Go to snmpcollector > Profiles > profile name > device name > metric family name.
    The Vendor Certification field contains the name of the active vendor certification.

How do I delete a deployed vendor certification?

Follow these steps:

  1. Go to the Quick Start page, and select the target snmpcollector instance.
  2. Go to the Select Device page.
  3. Select Delete Certification.
  4. Select the appropriate vendor certification name in the drop-down list.
  5. Click Delete.
    The Self-Certification Wizard deletes the vendor certification. The probe reruns discovery.

How do I know if my custom vendor certification is active?

Follow these steps:

  1. Open the snmpcollector probe configuration GUI.
  2. Go to snmpcollector > Profiles > profile name > device name > metric family name > component name.
  3. Select Options (icon) > Run Vendor Certification Test.
  4. Enter a delta delay in seconds. This value is the number of seconds between the two SNMP queries.
    A report with the test results for the active metrics with expressions appears.

Where can I find my custom vendor certifications on the deployment target?

Go to <Nimsoft>/probes/network/snmpcollector/CustomVendorCertifications on the snmpcollector instance.

Can I add more device information that is not related to metric data through the SelfCert portlet?

No. The tool only allows you to replace existing metric definitions.

How do I complete a vendor certification with expressions for more than one metric family?

This action is not supported by the SelfCert portlet. You can only modify one metric family per vendor certification.

Why can't I delete a MIB in the MIB File Manager?

You cannot delete any of the MIB files that are shipped with the snmpcollector probe. You can only delete the MIB files you load into the tool.

Does the MIB File Manager show MIB files that were added and loaded by other users?


Can I restore a MIB file to its default configuration?

The MIB File Manager only allows you to restore the MIB files you over-write.

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