Configuring Alarm Handling via SNMP

Sensor Management can receive SNMP messages (about alarms and other events) from managed elements and send them to various destinations, typically Operations Support Systems (OSS).

Sensor Management's support for handling messages via SNMP includes the following:

• SNMPv2 and SNMPv3 formats.
• Four SNMP destinations with IP addresses in IPv4 or IPv6 format.
• User-based Security Model (USM) users with different security profiles (SNMPv3 only).

Note: Sensor Management also receives alarms from managed elements via permanent CLI sessions. For more information, see "Alarms".

Overview of SNMP Configuration on Sensor Management

The following diagram gives an overview of the SNMP messaging you are aiming to set up on the network and how to configure it in Sensor Management. The UDP ports shown are the default settings.

Configuring Sensor Management to handle SNMP messages consists of these tasks:

• Configuring Sensor Management to:

  • Receive alarms from managed elements. See Configuring Sensor Management to Receive SNMP Messages from Elements.
  • Forward alarms to northbound destinations (up to four OSS). See "Configuring Sensor Management to Send SNMP Messages Northbound".

• For SNMPv3, creating USM users in Sensor Management that match USM users on the OSS systems.

• Configuring managed elements to send SNMP messages to Sensor Management (or to other systems).

  • By default, Sensor Management is an SNMP trap receiver for all managed elements. You can check or change this setting. See "Using Sensor Management as Default SNMP Receiver for All Elements".
  • If necessary, you can set up a configuration job to configure one or more trap receivers on managed elements. See "Setting Up an SNMP Trap Configuration Job".

Locating the SNMP Configurations

SNMP is configured in the Admin ▶ SNMP page. The SNMP page includes two tabs: Configuration and USM Users.

Configuring Sensor Management to Receive SNMP Messages from Elements

You configure Sensor Management to receive messages from managed elements in the Configuration tab of the Admin ▶ SNMP page.

Note: Sensor Management periodically resynchronizes the alarms from managed elements. Alarms will be received and displayed in real time via SNMP when Sensor Management is configured as explained in this section.

To configure Sensor Management to receive SNMP traps from elements

1. Select Admin ▶ SNMP to access the SNMP page (the Configuration tab is on top).

2. Enter values in the System name, Community string and UDP port fields. For more information on specific parameters, see the following table.

3. Click Apply.

SNMP configuration (Admin ▶ SNMP Configuration)

Note: You can test that you have entered the correct value for the community string by raising an alarm on an element. The alarm should be received and displayed in Sensor Management within five seconds. If the alarm is not received, check the community string used on one of the managed elements and enter it in this field.

Using Sensor Management as Default SNMP Receiver for All Elements

Sensor Management is the default SNMP trap receiver for all its managed elements.

You can change or check this setting in the Admin ▶ SNMP page.

1. Check or uncheck the box to enable or disable the use of Sensor Management as the default trap receiver for all managed elements.

Configuring Sensor Management to Send SNMP Messages Northbound

Sensor Management can forward the alarms that it receives from managed elements or generates internally to four destination systems.
Typically, the destinations are Operations Support Systems (OSS).

You configure Sensor Management to send messages to northbound systems in the four Trap receiver tabs at the bottom of the Configuration page.

Configuring Trap Receivers in the Admin ▶ SNMP (Configuration tab)

The messages sent to the destination system(s) include all events received from managed elements, as well as any loss of connectivity (LOC) events generated by Sensor Management itself. If there are no communication issues between Sensor Management and the destination systems, all events will have a corresponding clear event.

Outgoing SNMP messages can be sent as traps (unacknowledged) or as informs (require acknowledgement) in SNMP version 2c or version 3 format.

You can configure Sensor Management to send keep-alive events to the destination systems periodically. Keep-alive events contain the following information:

• The name of the Sensor Management system
• A counter for all events sent to the destination trap receiver since it was enabled.
  Note: Restarting Sensor Management or reconfiguring the trap receiver resets the counter to zero.
• Counters for all active alarms on the network (Total, Critical, Major, Minor, Warning, LoC [Loss of Contact]).

Keep-alive events help detect a lost connection and events missed by the destination system. The destination system can compare its count of received events with the keep-alive event count. It can also compare its current alarm count with alarms reported by Sensor Management. See the Sensor Management Administration Guide for a description of the MIB that defines keep-alive events for SNMP.

To configure northbound destinations (trap receivers)

1. Access the page Administration ▶ SNMP. The Configuration page is displayed.

2. Complete the parameters for one or more destinations (Trap receiver 1 to Trap receiver 4), as required. For more information on specific parameters, see the following table.

3. Click Apply.

Administration ▶ Configuration (Trap receivers for northbound destinations)

Trap receiver 1 to Trap receiver 4 Parameters:

Receiver state:
Check this box to enable sending SNMP messages from Sensor Management to the trap receiver on the destination system.

SNMP version:
Determines the SNMP version that Sensor Management will use when sending messages to the destination system.

Set this to the SNMP version expected by the destination system.

Possible values:

• SNMPV2c
• SNMP3

Notification type:
Determines the type of notification that Sensor Management will send to the destination system.

Set this to the type of SNMP message that the destination system is configured to receive.

Possible values:

• Notification: Select this option to send a trap (a message that does not require an acknowledgment).
• Inform: Select this option to send an inform (a message that requires an acknowledgment).

Community string:
This field is only active if SNMPv2c is selected as the SNMP version.

Community string that Sensor Management uses when sending SNMP messages to the destination system.

The value entered here on Sensor Management must match the value used on the destination system.

Keep-alive:
Check this box to send keep-alive messages to the destination system.

Note: In order for keep-alive messages to be sent, the Receiver state checkbox must also be checked.

USM user:
This field is only active if SNMPv3 is selected as the SNMP version.

Select a user that is defined on the destination system. A user account with the same credentials and security settings must also be defined in Sensor Management.

The values available in this field are the users that have been defined in the USM Users tab. For more information on creating and managing USM users, see "Managing USM Users (SNMPv3)".

UDP port:
Establishes the port on the destination system to which Sensor Management will send messages.

Set this to the UDP port that is set up on the destination system for receiving SNMP messages.

The default value is 162.

IP address:
IP address of the destination system.

Keep-alive frequency (s):
The frequency at which keep-alive messages are sent.

A value in seconds.

Keep-alive events are not affected by the volume of alarm messages sent.

Inform timeout (ms):
This field is only active if:

• SNMPv2 is selected as the SNMP version; and
• SNMP inform is selected as the Notification type.

The amount of time that Sensor Management will wait for an acknowledgment from the destination system before attempting to resend the message.

Inform retries:
This field is only active if:

• SNMPv2 is selected as the SNMP version; and
• SNMP inform is selected as the Notification type.

The number of times that Sensor Management will attempt to resend the message. If the message is not acknowledged after this number of retries, Sensor Management will stop trying to send the message.