Troubleshooting

Start from the failed plane.

Symptom	Likely cause	Check
eth_blockNumber stale	Execution sync lag or no consensus updates	eth_syncing, consensus logs, Engine auth.
Consensus synced but execution not updating	Engine API/JWT mismatch	Engine endpoint URL and shared JWT file.
WebSocket drops	Gateway idle timeout or client restart	Reconnect logs and backfill range.
eth_getLogs timeout	Range too large or archive data missing	Reduce block span; verify archive requirements.
Beacon API 403/404 through gateway	Protected route or wrong base path	Query local protected port 5052.

Prefer fixing endpoint policy and sync health over retry loops that hide node failures.