Prometheus got some undefined label

Playgrounds
,
#1

Hi, I was doing a promethus lab for setting node exporter and promethus I have used below promethues config but on prometheus UI I can see a undefined label, I want to know how this label "instance=“node01:9100” come

cat /etc/prometheus/prometheus.yml 
# my global config
global:
  scrape_interval: 15s # Set the scrape interval to every 15 seconds. Default is every 1 minute.
  evaluation_interval: 15s # Evaluate rules every 15 seconds. The default is every 1 minute.
  # scrape_timeout is set to the global default (10s).

# Alertmanager configuration
alerting:
  alertmanagers:
    - static_configs:
        - targets:
          # - alertmanager:9093

# Load rules once and periodically evaluate them according to the global 'evaluation_interval'.
rule_files:
  # - "first_rules.yml"
  # - "second_rules.yml"

# A scrape configuration containing exactly one endpoint to scrape:
# Here it's Prometheus itself.
scrape_configs:
  - job_name: "nodes"
    static_configs:
      - targets: ["node01:9100"]
        labels: 
          node: "node01"
      - targets: ["node02:9100"]
        labels: 
          node: "node02"

  # The job name is added as a label `job=<job_name>` to any timeseries scraped from this config.
  - job_name: "prometheus"

    # metrics_path defaults to '/metrics'
    # scheme defaults to 'http'.

    static_configs:
      - targets: ["localhost:9090"]
       # The label name is added as a label `label_name=<label_value>` to any timeseries scraped from this config.
        labels:
          app: "prometheus"
#2

Hi @apradhan

It’s populated from the targets entry in your config. Prometheus adds this label to identify each scraped target.
Did you try refreshingthe UI?

1 Like
#3

Thank you @Santosh_KodeKloud that really clears my doubt. I want to learn thanos can you refer me any course or quick guide rather than thanos document it would be helpful. Thank you once again.