NDM Troubleshooting

Overview

Use the information below for troubleshooting Datadog Network Device Monitoring. If you need additional help, contact Datadog support.

Terminology

SNMP - Simple network management protocol
A network protocol that is used to collect information about bare metal networking gear.
OID - Object identifier
A unique ID or address on a device that when polled returns the response code of that value. For example, OIDs are CPU or device fan speed.
sysOID - System object identifier
A specific address that defines the device type. All devices have a unique ID that defines it. For example, the Meraki base sysOID is 1.3.6.1.4.1.29671.
MIB - Managed information base
A database or list of all the possible OIDs and their definitions that are related to the MIB. For example, the IF-MIB (interface MIB) contains all the OIDs for descriptive information about a device’s interface.

FAQ

What SNMP versions does Datadog support?

Datadog supports all three versions of SNMP: SNMPv1, SNMPv2, and SNMPv3.

What protocol does Datadog use to discover devices?

Datadog uses SNMP to discover devices. During discovery, the SNMP port (default 161) is polled. If there’s a response and a profile to match, this is considered a discovered device.

Does Datadog do MIB certification? Do I need to send you all my MIBs? How do I convert my MIBs with Python?

The Datadog Agent is MIB-less, meaning you don’t need to do anything with your MIBs. All metrics collected with Datadog device profiles automatically work without the MIB.

To add metrics or a custom configuration, list the MIB name, table name, table OID, symbol, and symbol OID, for example:

- MIB: EXAMPLE-MIB
    table:
      # Identification of the table which metrics come from.
      OID: 1.3.6.1.4.1.10
      name: exampleTable
    symbols:
      # List of symbols ('columns') to retrieve.
      # Same format as for a single OID.
      # Each row in the table emits these metrics.
      - OID: 1.3.6.1.4.1.10.1.1
        name: exampleColumn1

Can I still use Network Device Monitoring if my device-model pair isn’t supported?

Datadog collects generic base-line metrics from all devices. If there are unsupported metrics from a vendor MIB, you can write a custom profile, or send a feature request to Datadog support.

If you send a feature request, Datadog support needs a snmpwalk from the requested device. Run the following and send the output:

snmpwalk -O bentU -v 2c -c <COMMUNITY_STRING> <IP_ADDRESS>:<PORT> 1.3.6

Why am I only seeing one metric collected for my networks and it’s the number of devices collected at zero?

  1. Try loosening ACLs/firewall rules for your devices.
  2. Run snmpwalk -O bentU -v 2c -c <COMMUNITY_STRING> <IP_ADDRESS>:<PORT> 1.3.6 from the host your Agent is running on. If you get a timeout without any response, there is likely something blocking the Datadog Agent from collecting metrics from your device.

What do I do if Datadog supports a vendor or device type but my specific model isn’t supported?

  • Contact Datadog support to put in a request to support your specific model.

  • Extend your profiles to support additional sysobjectid values. For example, if you want to monitor another type of Cisco CSR, you can modify the ISR profile directly to list another sysobjectid like this:

    	snmpwalk -v 2c -c [community string] [ip address] 1.3.6.1.2.1.1.2

Note: If you do not know the sysobjectid of your device, try doing an Internet search or run a snmpwalk on a host that can reach out to your device. Use the output to list the profile to match against.

How do I extract information about devices and interfaces of my network devices?

Further Reading

Additional helpful documentation, links, and articles:

Monitor SNMP with DatadogBLOG more more