Edge Delta Metrics

Edge Delta ingests metrics signals and it calculates metrics from logs.


Metrics, logs and traces are types of signals emitted by (properly instrumented) applications or systems to enable monitoring and troubleshooting. Metrics are numeric data or measurements of a system and the data is usually aggregated over time.

Metric Signals vs Log to Metric

There are two types of metrics in Edge Delta. Log to metrics are measurements that are derived by measuring the content of logs. For example, the rate of 4xx errors reported in logs that are emitted by NGINX servers can be determined by examining /var/log/nginx/error.log, identifying 4xx error logs, and counting the number of such errors for a specific duration.

Metric signals, on the other hand, are generated directly by the data source and emitted as metric signals. For example, the rate of 4xx errors being reported by NGINX servers can be determined by consuming metric signals from an nginx-prometheus-exporter.

Metric Signals Examples

  • Golden Signals: CPU, RAM, Network
  • Kubernetes Metrics: kubeapi, kubelet, cAdvisor
  • Kube State Metrics: kube_secret_type{namespace="vm",secret="vm-grafana",type="Opaque"} 1
  • Application Metrics:
    • Metrics that are generated by applications directly, either alongside or instead of log data such as nginxplus_upstream_server_responses{code=”4xx”,server=””,upstream”my_servers”} 23451
    • Raw state metrics such as Google Nest metrics: nest_ambient_temperature{id="abcd1234",label="Living-Room",scale=”fahrenheit”} 72

Metric Signal Sources

  • Linux/VM
    • eBPF (node, syscall)
    • System (various exporters like node_exporter, /proc)
  • Docker
    • Linux + cadvisor (container metrics)
  • Kubernetes
    • Docker + cadvisor (kubelet) + KSM (Kube State Metrics, kubeapi)
  • Custom Metrics
    • Any/all of the other metric signal sources
    • Custom exporters from infrastructure and app providers (Cilium, NGINX, Mongo, etc)

Edge Delta Metrics

The Edge Delta SaaS can ingest metric signals with full dimensions from the agent, including Kubernetes Source metrics. It handles metrics routing on the edge using Visual Pipelines and you can build custom dashboards in the Edge Delta web app.

Feature Status

Metrics have the following prerequisites:

  1. To ingest Kube State Metrics, KSM must be deployed in the same cluster as the Edge Delta agent.
  2. To ingest node-exporter metrics, node-exporter must be deployed in the same cluster as the Edge Delta agent.
  3. All metric processing nodes, such as logs to metrics nodes, must be connected to the Metrics Output node.