DHCP Services

This solution guide will walk you through setting up Observability for DHCP Services using Orb agents. This is a monitoring configuration that can be used when monitoring of DHCP services is required.

Configure Observation

The first step is to configure what data the agents should be observing. This is done by defining and configuring what Tap the agents should be listenining on.

The default PCAP (Packet Capture) tap configuration is all that is necessary for DHCP monitoring. Your agent tap configurations should look something like this:

YAMLJSON

taps:
    default_pcap:
        interface: "visor.module.input/1.0"
        input_type: pcap
        config:
            iface: "auto"

{
    "taps": {
        "default_pcap": {
            "config": {
                "iface": "auto",
            },
            "input_type": "pcap",
            "interface": "visor.module.input/1.0"
        }
    }
}

If you want to explicitely specify the interface the PCAP tap should be listening on (instead of using the auto selection), please ensure that the iface is configured with the appropriate interface name. If the interface defined is not correct, you will need to re-run the agent provisioning command specifying the correct interface using the PKTVISOR_PCAP_IFACE_DEFAULT environment variable.

Configure Analysis

The second step is to configure the agents to analyze for DHCP traffic. This is done by defining and applying a tailored Policy to the agents.

Create a Policy

The following is a sample policy that includes the NET and DHCP handlers, as well as a BPF filter to restrict analyzed data to DHCP traffic. Your policy should look something like this:

YAMLJSON

handlers:
    modules:
        handler_dns_1:
            type: dhcp
        handler_net_1:
            type: net
input:
    input_type: pcap
    tap: default_pcap
    filter:
        bpf: 'port 67 or port 68'
kind: collection

"handlers": {
    "modules": {
        "handler_dhcp_1": {
            "type": "dhcp"
        },
        "handler_net_1": {
            "type": "net"
        }
    }
},
"input": {
    "input_type": "pcap",
    "tap": "default_pcap",
    "filter": {
        "bpf": "port 67 or port 68"
    }
},
"kind": "collection"

For a more tailored DHCP policy to filter on specific traffic or to add (or exclude) specific metrics, please refer to the Orb Policy Reference.

Applying your policy

The final step is to apply your policy by creating a Dataset, which links your agents (through an Agent Group) with your policy and the Sink where you want to send your metrics.