Installing the gateway collector (optional)

Install the gateway collector (edb-otelcol), a centralized OpenTelemetry Protocol (OTLP) ingestion endpoint, to receive telemetry data (metrics, logs, and traces) from external sources and forward it to ClickHouse.

You need a dedicated gateway collector only when multiple systems or clusters send observability data to the same ClickHouse instance, or when applications outside your WHPG cluster need to ship telemetry to ClickHouse. If your deployment consists of a single WHPG cluster sending data directly to ClickHouse, skip this page, WEM auto-provisions the gateway collector for you.

Installing the gateway collector

Install the package on a host reachable from both your WHPG cluster nodes and ClickHouse, typically the same host as ClickHouse itself.

1. Configure the EDB repository, then install the gateway collector package:

   → WrapCopy

   export EDB_SUBSCRIPTION_TOKEN=<your-token>
   export EDB_REPO=gpsupp
   curl -1sSLf "https://downloads.enterprisedb.com/$EDB_SUBSCRIPTION_TOKEN/$EDB_REPO/setup.rpm.sh" | sudo -E bash
   sudo yum install -y edb-otelcol

2. The package ships /etc/edb/otelcol/config.yaml. Replace the whole file with the following content:

   → WrapCopy

   sudo tee /etc/edb/otelcol/config.yaml << 'EOF'
   receivers:
     otlp:
       protocols:
         grpc:
           endpoint: "0.0.0.0:4317"
         http:
           endpoint: "0.0.0.0:4318"
   
   exporters:
     clickhouse:
       endpoint: "clickhouse://default:<password>@localhost:9000"
       database: acp_observability
       timeout: 5s
       retry_on_failure:
         enabled: true
         initial_interval: 5s
         max_interval: 30s
         max_elapsed_time: 300s
   
   processors:
     batch:
       timeout: 5s
       send_batch_size: 8192
   
   service:
     pipelines:
       metrics:
         receivers: [otlp]
         processors: [batch]
         exporters: [clickhouse]
       logs:
         receivers: [otlp]
         processors: [batch]
         exporters: [clickhouse]
       traces:
         receivers: [otlp]
         processors: [batch]
         exporters: [clickhouse]
   EOF

   Under endpoint:

   • Replace default with your ClickHouse username. default is ClickHouse's built-in user, and what Installing ClickHouse uses as an example.
   • Replace <password> with that user's password.
   • Replace localhost with your ClickHouse host if the gateway collector runs on a different host than ClickHouse.

   Optionally, add a prometheus exporter alongside clickhouse to also expose a scrape endpoint for an external Prometheus instance, without giving up the ClickHouse write path:

   → WrapCopy

   exporters:
     clickhouse:
       # ...
     prometheus:
       endpoint: "0.0.0.0:8889"
   
   service:
     pipelines:
       metrics:
         receivers: [otlp]
         processors: [batch]
         exporters: [clickhouse, prometheus]

   Only the metrics pipeline supports the prometheus exporter. Logs and traces still export to ClickHouse only.

3. Start the gateway collector:

   → WrapCopy

   sudo systemctl daemon-reload
   sudo systemctl enable edb-otelcol
   sudo systemctl start edb-otelcol
   sudo systemctl status edb-otelcol

4. Verify the gateway collector is listening and forwarding data:

   → WrapCopy

   # Check the gateway is listening
   ss -tlnp | grep -E '4317|4318'
   
   # Check logs for errors
   journalctl -u edb-otelcol -n 20 --no-pager

Next steps

Continue to Installing WEM.