Monitoring & Alerts

Running a validator requires 24/7 visibility into node health, consensus participation, and resource usage. This guide covers setting up Prometheus and Grafana for Mersennet monitoring, plus recommended alert rules.

Overview

A typical monitoring stack includes:

Component	Purpose
Prometheus	Scrapes metrics from the Mersennet node
Grafana	Dashboards and visualization
Alertmanager	Routes alerts (email, Slack, PagerDuty)

Key Metrics

Mersennet exposes metrics that you should monitor:

Metric	Description
prime_chain_block_height	Current block height; should increase steadily
prime_chain_total_stake	Total staked PRIM across all validators
prime_chain_tx_count	Transaction count (per block or cumulative)
prime_chain_pending_txs	Mempool size; high values may indicate congestion
prime_chain_peer_count	Number of connected P2P peers
prime_chain_validator_missed_blocks	Blocks you failed to sign (slashing risk)

tip

Metric names may vary by implementation. Check your node's /metrics endpoint or documentation for the exact names.

Prometheus Setup

1. Install Prometheus

# Ubuntu/Debian
sudo apt update
sudo apt install prometheus

# Or use the official binary
wget https://github.com/prometheus/prometheus/releases/download/v2.45.0/prometheus-2.45.0.linux-amd64.tar.gz
tar xvfz prometheus-*.tar.gz
cd prometheus-*

2. Configure Scraping

Edit prometheus.yml:

global:
  scrape_interval: 15s
  evaluation_interval: 15s

scrape_configs:
  - job_name: 'prime-chain'
    static_configs:
      - targets: ['localhost:9091']  # Mersennet metrics port

Ensure your Mersennet node exposes metrics on the configured port (e.g. 9091). The exact port is set in the node config.

3. Start Prometheus

./prometheus --config.file=prometheus.yml

Grafana Setup

1. Install Grafana

# Ubuntu/Debian
sudo apt install -y software-properties-common
sudo add-apt-repository "deb https://packages.grafana.com/oss/deb stable main"
wget -q -O - https://packages.grafana.com/gpg.key | sudo apt-key add -
sudo apt update
sudo apt install grafana
sudo systemctl enable grafana-server
sudo systemctl start grafana-server

2. Add Prometheus Data Source

1. Open Grafana at http://localhost:3000
2. Login (default: admin/admin)
3. Configuration → Data Sources → Add data source
4. Select Prometheus
5. URL: http://localhost:9090
6. Save & Test

3. Import or Create Dashboards

Create panels for:

• Block height — Graph of prime_chain_block_height over time
• Total stake — Gauge or stat for prime_chain_total_stake
• Transaction count — Rate of prime_chain_tx_count
• Pending transactions — prime_chain_pending_txs
• Peer count — prime_chain_peer_count
• Missed blocks — prime_chain_validator_missed_blocks (critical for validators)

Alert Rules

Configure Prometheus alerting to catch issues before they cause slashing or downtime.

Prometheus Alert Rules

Create alerts.yml (or add to prometheus.yml):

groups:
  - name: prime-chain
    rules:
      # Block production stalled
      - alert: MersennetBlockStalled
        expr: increase(prime_chain_block_height[5m]) == 0
        for: 2m
        labels:
          severity: critical
        annotations:
          summary: "Mersennet block production stalled"
          description: "No new blocks in 5 minutes. Node may be out of sync or consensus may be stuck."

      # Missed blocks (slashing risk)
      - alert: MersennetMissedBlocks
        expr: increase(prime_chain_validator_missed_blocks[1h]) > 0
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "Validator missed blocks"
          description: "Validator has missed blocks in the last hour. Risk of downtime slashing."

      # Low disk space
      - alert: MersennetLowDiskSpace
        expr: (node_filesystem_avail_bytes{mountpoint="/"} / node_filesystem_size_bytes{mountpoint="/"}) < 0.1
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "Low disk space on Mersennet node"
          description: "Less than 10% disk space remaining. Node may stop if disk fills."

      # Peer count too low
      - alert: MersennetLowPeerCount
        expr: prime_chain_peer_count < 3
        for: 10m
        labels:
          severity: warning
        annotations:
          summary: "Low P2P peer count"
          description: "Fewer than 3 peers connected. Network connectivity may be degraded."

Reference the rules file in prometheus.yml:

rule_files:
  - 'alerts.yml'

Alertmanager (Optional)

To send alerts to email, Slack, or PagerDuty:

1. Install Alertmanager
2. Configure receivers (e.g. Slack webhook)
3. Set alertmanager.url in Prometheus config

Best Practices

Practice	Recommendation
Uptime	Aim for 99.9%+ to avoid downtime slashing
Disk	Monitor and expand before hitting 10% free
Peers	Maintain at least 5–10 stable peers
Backups	Backup validator key and config; never expose the key
Alerts	Route critical alerts to a channel you monitor 24/7

Next Steps

• Validator Overview — Understand validator roles and risks
• Staking Guide — Manage stake and delegations