PrometheusNotConnectedToAlertmanager in agent mode

[dannyZhou]

# agent device

/opt/prometheus-agent/prometheus/prometheus \
  --config.file /opt/prometheus-agent/prometheus-config/agent-aaa/prometheus.yml \
  --web.config.file /opt/prometheus-agent/prometheus-config/agent-aaa/web.yml \
  --storage.agent.path=/opt/prometheus-agent/data-agent \
  --web.listen-address=:19090

# main server 

/opt/prometheus/prometheus/prometheus \
  --config.file /opt/prometheus/prometheus-config/main-server/prometheus.yml \
  --web.config.file /opt/prometheus/prometheus-config/main-server/web.yml \
  --storage.tsdb.path /opt/prometheus/prometheus-tsdb/ \
  --web.console.templates=/opt/prometheus/prometheus/consoles \
  --web.console.libraries=/opt/prometheus/prometheus/console_libraries \
  --web.enable-remote-write-receiver

Consider skip agent server ?