works eventually, still shaky

docker-compose.yml

@@ -17,6 +17,7 @@ services:
       - DATABASE_URL=ecto://postgres:postgres@db/backend_dev
       - SECRET_KEY_BASE=W8nGKNhNR8vKj6A4VnwN5h5h7RZvkKmZPqxqzLzYxXGQqC6HnKp2Wm8MNqKpQxZv
       - CLUSTER_NODES=backend@phoenix1,backend@phoenix2,backend@phoenix3
+      - OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector:4318
     ports:
       - "4001:4000"
     healthcheck:
@@ -41,6 +42,7 @@ services:
       - DATABASE_URL=ecto://postgres:postgres@db/backend_dev
       - SECRET_KEY_BASE=W8nGKNhNR8vKj6A4VnwN5h5h7RZvkKmZPqxqzLzYxXGQqC6HnKp2Wm8MNqKpQxZv
       - CLUSTER_NODES=backend@phoenix1,backend@phoenix2,backend@phoenix3
+      - OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector:4318
     ports:
       - "4002:4000"
     healthcheck:
@@ -65,6 +67,7 @@ services:
       - DATABASE_URL=ecto://postgres:postgres@db/backend_dev
       - SECRET_KEY_BASE=W8nGKNhNR8vKj6A4VnwN5h5h7RZvkKmZPqxqzLzYxXGQqC6HnKp2Wm8MNqKpQxZv
       - CLUSTER_NODES=backend@phoenix1,backend@phoenix2,backend@phoenix3
+      - OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector:4318
     ports:
       - "4003:4000"
     healthcheck:
@@ -73,6 +76,18 @@ services:
       timeout: 5s
       retries: 5
 
+  nginx-lb:
+    image: nginx:alpine
+    container_name: nginx-lb
+    volumes:
+      - ./nginx-lb.conf:/etc/nginx/conf.d/default.conf
+    ports:
+      - "4000:80"
+    depends_on:
+      - phoenix1
+      - phoenix2
+      - phoenix3
+
   client:
     build:
       context: ./client
@@ -80,3 +95,17 @@ services:
     container_name: client
     ports:
       - "5173:80"
+    depends_on:
+      - nginx-lb
+
+  otel-collector:
+    image: otel/opentelemetry-collector-contrib:latest
+    container_name: otel-collector
+    command: ["--config=/etc/otel-collector-config.yaml"]
+    volumes:
+      - ./otel-collector-config.yaml:/etc/otel-collector-config.yaml
+    ports:
+      - "4318:4318" # OTLP HTTP receiver
+      - "4317:4317" # OTLP gRPC receiver
+      - "8888:8888" # Prometheus metrics
+      - "8889:8889" # Prometheus exporter metrics