Sequencer Uptime Monitor

WHAT IT DOES

This tool monitors sequencer uptime and performance by analyzing on-chain block production, heartbeats, and block interval data. It provides a comprehensive view of sequencer health, showing which sequencers are online, degraded, or offline, along with their uptime percentages, block production counts, and last activity timestamps. The tool analyzes block production patterns, missed block detection, and heartbeat events to assess sequencer reliability. Results are presented as a detailed uptime dashboard with status indicators, uptime bars, and performance metrics. This is essential for L2 operators monitoring sequencer health, developers tracking network reliability, and stakeholders ensuring consistent block production.

HOW TO USE

Connect your wallet (read-only, no transaction required) and select the target network. Enter the sequencer name and contract address, and set the lookback blocks for uptime analysis. Click "monitor uptime" and the tool will verify the sequencer contract, analyze historical block production data and heartbeat events, and generate a comprehensive uptime report. Results display a summary with online/degraded/offline counts and overall uptime percentage, detailed uptime cards showing each sequencer's status, uptime, block count, last activity, and a visual uptime bar, and a table of all sequencers with their metrics. Use the report to monitor sequencer health, identify performance degradation, and ensure reliable block production.

TECHNICAL MECHANISM

The monitor uses ethers.js v5.7.2 to perform a multi-stage uptime analysis. First, it calls eth_getCode to verify the sequencer contract is deployed and uses block explorer APIs to fetch verification status and source code. The tool then scans historical block headers and logs using eth_getLogs across the specified block range to identify block production events, heartbeat events, and sequencer registration/status changes. It analyzes block timestamps to calculate block intervals and detect missed blocks or production gaps. For each sequencer, the tool computes uptime percentage based on expected block production versus actual blocks produced. It also tracks last block production time, block count, and status based on recent activity (online if producing blocks within expected intervals, degraded if intermittent delays, offline if no recent production). Results are compiled into a structured report with detailed sequencer metrics, status indicators, and uptime visualizations.

WHAT IT CANNOT SEE

This tool cannot predict sequencer downtime or future availability—it provides analysis based on historical data. It is limited by the RPC provider's rate limits and block range availability for historical block data. It cannot detect sequencer issues that do not result in on-chain state changes or missed blocks, such as performance degradation without block loss. The analysis relies on the accuracy and completeness of on-chain block data and contract events; incomplete logs may produce incomplete results. It cannot analyze contracts that are not verified or have opaque sequencer mechanisms where heartbeat events are not emitted. The tool is limited to the specific sequencer contracts and block ranges that are accessible via RPC. It cannot guarantee that uptime metrics reflect actual sequencer performance without manual review and cross-verification with external monitoring tools. The status indicators are heuristic and based on the selected lookback period and block production patterns.

PLEASE NOTE

This is a read‑only analytics tool—it never submits transactions or modifies sequencer state. It is designed for EVM‑compatible chains with sequencer contracts that emit block production and heartbeat events. The uptime results are for informational and monitoring purposes only and should not be considered a comprehensive performance audit. Always cross-verify sequencer health with multiple monitoring sources. The tool's status thresholds are configurable and may need adjustment based on your specific sequencer's expected block production intervals and network conditions.