How to Configure the SNMP Trap Service

The NetSight SNMP Trap Service (snmptrapd) receives SNMP trap and inform messages from your network devices and logs them into the Event Log. SNMPv1/v2 traps are sent by devices using a community name, and are accepted by the Trap Service regardless of what the community name is. For SNMPv3 traps and informs, the Trap Service must know the credentials (user name/passwords) and the SNMP Engine ID (required for traps) of the sending agent on the device before a trap or inform can be received. This information is configured in the snmptrapd.conf file. If this information is not configured, trap and inform messages will be dropped by the Trap Service. For more information, see Traps and Informs.

Use the Trap Receiver Configuration window to configure the information needed to receive trap information from the devices on your network. The window lets you create a list of IP addresses of the systems that will receive traps (trap receiver addresses). It also lets you configure the snmptrapd.conf file with the credentials and Engine IDs required for your SNMPv3 devices.

Instructions on:

Configuring Trap Receivers

Use these steps to create a list of trap receiver addresses. These are the addresses of the systems that will receive trap information from your network devices.

  1. In Console's left-panel tree, right-click on one or more devices or device groups, and select Trap Receiver Configuration. The Trap Receiver Configuration window opens.
  2. In the Configuration tab, the table at the bottom lists the selected devices and their current trap receiver information.
  3. In the top table, create a list of trap receiver addresses to set on the devices. When the Trap Receiver Configuration window is initially opened, this table lists the Console workstation as the only trap receiver. Click the Update From All/Selected Devices button to update the table with the current trap receiver information from the selected devices. You can also manually add trap receivers to the table, using the right-click menu, tab key, and arrow keys. Tab through the table columns and modify each entry as desired:
    1. Check the Configure checkbox if you want this particular trap receiver entry to be set on the selected devices when you Apply your trap receiver configuration settings.
    2. Use the Priority column to specify the order in which trap receiver entries will be set on the selected devices, with the lowest number having the highest priority. When you Apply your trap receiver settings, Console writes the Trap Receiver IPs to each device in order, starting with the highest priority (the lowest number) until all are written or a device cannot accept any more.
    3. Enter the Trap Receiver IP address for a trap receiver (the system where devices will send traps). Trap receivers systems must be running an SNMP Trap Service.
    4. Select the supported message type: Trap, Inform, or Both.
    5. Use the drop-down list to select the Trap Credential for the trap receiver. Note that when a credential appears within angle brackets (< credential name>), it indicates that the community or user name could not be found among the credentials created in Console. When this happens, a temporary credential name is created, derived from the community or user name on the device.
  4. If desired, select the checkbox to remove or update existing trap receiver IPs on devices during Apply operation. When checked, an Apply operation will update the Trap Configuration table on the devices to match the enabled entries in this table, by adding, modifying, and removing entries as necessary. Entries on the device that were created via CLI are never deleted or modified. When unchecked, an Apply operation will add entries from this table to the devices Trap Configuration table. Existing entries on the devices are not modified in any way and no duplicate addresses are created.
  5. In the Trap Receivers on Devices table, select the devices that you want to apply the configuration to. If no devices are selected, then all devices in the table will be updated. Click Apply to All/Selected Devices to write (set) the trap receiver IPs listed in the Trap Receiver Configuration table to the selected devices.

Configuring the snmptrapd.conf File

Use these steps to configure the snmptrapd.conf file with the credential and Engine ID information required for SNMPv3 devices.

  1. In Console's left-panel tree, right-click on one or more devices or device groups, and select Trap Receiver Configuration. The Trap Receiver Configuration window opens.
  2. Click the snmptrapd tab. The Credential Table is displayed listing the credential information for the selected devices.
  3. The Credential Name column can be edited by clicking on the column to display a drop-down list that contains all SNMPv3 credentials from the NetSight database. (Go to the Authorization/Device Access - Profiles/Credentials tab to create a credential, if necessary.) Once an edit is made, an asterisk is displayed in the Modified column to show which rows were changed.
  4. You can also add new entries to the table. Click Add Entry to add a new row to the table. The Credential Name column will display the ReadOnly credential for the default Profile. The Engine ID and Credential Name columns can be configured for new rows. An Engine ID is only necessary for devices sending trap messages; it is not necessary for informs.
  5. Select the rows you want to add to the snmptrapd.conf file, and click Add Entry.
     NOTES:
    1. You can also add entries to the configuration file by typing user credentials directly into the snmptrapd.conf Text area. Refer to the information in the Text area for instructions and examples.
    2. To modify an entry you have added to the file, you must first remove the entry from the file and then add a new entry via the table. To remove entries from the snmptrapd.conf file, you must select the entry in the Text area, and press Delete.
  6. Click Save and Close. The user credentials have been added to the snmptrapd.conf file.
  7. After making changes, you must restart the SNMP Trap Service on the NetSight Server. Refer to Restarting the SNMP Trap Service for more information.
  NOTES:
  1. You can manually add user information directly to the snmptrapd.conf file using a text editor. Instructions are provided in the snmptrapd.conf file located on the server in the <install directory>\appdata directory.
  2. The snmptrapd.conf file is not preserved during the Console Uninstall.

Restarting the SNMP Trap Service

Depending on the system where the NetSight Server is running, there are several ways to restart the SNMP Trap service.

Restarting the service locally on the NetSight Server host system:

Windows Linux
Using the Services Manager:
  1. Go to the Taskbar Notification Area of your desktop (on the lower right of your screen, unless you've relocated your Taskbar).
  2. Locate the Services Manager icon ( ) and right-click it.
  3. Select SNMPTrap  >  Restart.

Using Windows Services:
  1. From the Control Panel, access the Administrative Tools > Services window.
  2. Locate the snmptrapd service and select "Restart the service."
  1. Navigate to the etc/init.d directory.
  2. Type the command:
    nssnmptrapd stop
  3. Press Enter.
  4. Type the command:
    nssnmptrapd start
  5. Press Enter.

Restarting the service remotely from a NetSight Client host system:

Windows Linux
Restarting the service remotely on Windows host systems is only possible if both the Client and Server are capable of running Remote Desktop (a feature of Windows XP Professional) or through the use of a third-party facility that provides similar capabilities to Remote Desktop.

When you can access the Services Manager on the remote system using either Remote Desktop or a third-party program, you can restart the service as follows:

  1. Go to the Taskbar Notification Area of the remote desktop.
  2. Locate the Services Manager and right click the icon ( ).
  3. Select SNMPTrap  >  Restart.
  1. Telnet to the server and login as an administrative user.
  2. Navigate to the etc/init.d directory.
  3. Type the command:
    nssnmptrapd stop
  4. Press Enter.
  5. Type the command:
    nssnmptrapd start
  6. Press Enter.
  7. Log out and close the telnet session.

Related Information

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