Gateway Mode Architecture

Overview

In Gateway Mode, one or more centralised OTel Collector instances receive from all application pods and forward to xScaler. No OpAMP supervision is used — configuration is managed via Kubernetes ConfigMaps or Helm.

Gateway Config (Production Helm Template)

Based on ``:

receivers:
  otlp:
    protocols:
      grpc:
        endpoint: 0.0.0.0:4317
      http:
        endpoint: 0.0.0.0:4318

  prometheus:
    config:
      scrape_configs:
        - job_name: mimir-distributor
          dns_sd_configs:
            - names:
                - "AAAA+mimir-distributor.xscaler-edge.svc.cluster.local"
              type: AAAA
              port: 8080
          metric_relabel_configs:
            - source_labels: [__name__]
              action: keep
              regex: "xscalor_ext_authz_.*|xscalor_proxy_auth_.*"

processors:
  memory_limiter:
    check_interval: 1s
    limit_mib: 512
    spike_limit_mib: 128
  batch:
    timeout: 5s
    send_batch_size: 2048
  attributes/cluster:
    actions:
      - key: xscaler_cluster
        value: "{{ .Release.Namespace }}"
        action: upsert

exporters:
  prometheusremotewrite:
    endpoint: "{{ .Values.otelCollector.remoteWrite.endpoint }}"
    headers:
      X-Scope-OrgID: <your-tenant-id>

service:
  pipelines:
    metrics:
      receivers: [otlp, prometheus]
      processors: [memory_limiter, batch, attributes/cluster]
      exporters: [prometheusremotewrite]

Comparison: Agent Mode vs Gateway Mode

Feature	Agent Mode	Gateway Mode
Deployment	DaemonSet (one per node)	Deployment (N replicas)
Config mgmt	OpAMP push from portal	ConfigMap + Helm
Host metrics	✅ Native (hostmetrics receiver)	❌ Requires separate DaemonSet
Log files	✅ Native (filelog receiver)	❌
Kubernetes scrape	✅ Per-node k8s SD	✅ Cluster-wide
Central aggregation	❌	✅
Config rollback	Portal revision history	Git revert + kubectl
Secret management	KMS via agent-api	Kubernetes Secrets

---

← Previous: Agent Mode
Next: Lab 01 — Tenant Creation →