Skip to main content
Verify that your Arc node is syncing, diagnose issues from logs, and set up Prometheus metrics scraping.

​
Prerequisites

​
Step 1. Check service status

If your node runs as systemd services, check the status of both processes: 
sudo systemctl status arc-execution
sudo systemctl status arc-consensus
Both services display Active: active (running) in their output. If either service has failed, review the logs in Step 3.

​
Step 2. Check block height

Query the local RPC endpoint to confirm the node is syncing: 
cast block-number --rpc-url http://localhost:8545
Run this command several times over a few seconds. The block number increases steadily, confirming the node is syncing: 
# First run:
1234567

# Second run (a few seconds later):
1234572
To view the latest block details: 
cast block --rpc-url http://localhost:8545
Example output: 
baseFeePerGas        7
difficulty           0
gasLimit             30000000
gasUsed              21000
hash                 0xabc123...
number               1234572
timestamp            1711234567
transactions:        [0xdef456...]

​
Step 3. View the logs

Stream real-time logs for each service: 
# Execution Layer logs
sudo journalctl -u arc-execution -f

# Consensus Layer logs
sudo journalctl -u arc-consensus -f
If your node is not running as a systemd service, check the terminal output where each process is running. What to look for:
  • Healthy: Log entries showing new blocks being imported, increasing block heights
  • Unhealthy: Repeated connection errors to relay endpoints, IPC socket failures, or no new blocks for an extended period

​
Step 4. Set up metrics scraping

Both the Execution Layer and Consensus Layer expose Prometheus-compatible metrics endpoints:
EndpointDescription
http://localhost:9001/metricsExecution Layer metrics
http://localhost:29000/metricsConsensus Layer metrics
The metrics endpoints are only available if the --metrics flag was passed when starting the node. The Deploying a Node as a Service guide includes this flag in the systemd service files.Verify the endpoints are accessible:
curl -s http://localhost:9001/metrics | head -5
curl -s http://localhost:29000/metrics | head -5
Both commands return Prometheus-formatted text metrics. Example output:
# HELP reth_sync_stage_checkpoint Stage checkpoint block number
# TYPE reth_sync_stage_checkpoint gauge
reth_sync_stage_checkpoint{stage="Headers"} 1234567
If either returns an empty response or connection error, confirm the --metrics flag is set in your startup command.
Add the following scrape targets to your Prometheus configuration: 
scrape_configs:
  - job_name: "arc-execution"
    static_configs:
      - targets: ["localhost:9001"]

  - job_name: "arc-consensus"
    static_configs:
      - targets: ["localhost:29000"]
After reloading Prometheus, verify that both targets appear as UP in the Prometheus targets page (http://localhost:9090/targets).