Monitor Monitoring

Lightweight monitoring solution in a single 7MB binary. Monitors HTTP/HTTPS endpoints, DNS records, and TCP ports with instant notifications via Telegram, Slack, Discord, or Mattermost.

Features

• Concurrent monitoring - Parallel endpoint checks with configurable concurrency limits
• Multi-protocol support - HTTP/HTTPS, DNS (A/AAAA/CNAME), and TCP monitoring
• Smart failure detection - Configurable failure thresholds with automatic retry logic
• Multi-channel notifications - Telegram, Slack, Discord, and Mattermost support with fallback mechanism
• Intelligent batching - Anti-spam protection with configurable batch windows and size limits
• Production-ready - Memory monitoring, graceful shutdown, structured logging
• Zero dependencies - Single binary with no external runtime dependencies
• 12-factor app - Environment variable configuration
• Built-in retry - Automatic retry on failed checks with configurable delays

Quick Start

1. Setup Notification Channel

Telegram (Recommended)

Create bot:

1. Message @BotFather on Telegram
2. Send /newbot and follow prompts
3. Save the bot token (format: 123456789:ABC-DEF1234ghIkl-zyx57W2v1u123ew11)

Get chat ID:

• Add @userinfobot to your group/channel
• Send any message and copy the ID shown
• Or visit: https://api.telegram.org/bot<YOUR_TOKEN>/getUpdates after sending a message to your bot

Add bot to channel/group:

• Add your bot as administrator to receive notifications

Slack

1. Create incoming webhook at https://api.slack.com/messaging/webhooks
2. Copy webhook URL (format: https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXX)

Discord

1. Edit channel → Integrations → Webhooks → New Webhook
2. Copy webhook URL (format: https://discord.com/api/webhooks/123456789012345678/abcdefghijklmnopqrstuvwxyz)

Mattermost

1. Integrations → Incoming Webhooks → Add Incoming Webhook
2. Copy webhook URL (format: https://mattermost.example.com/hooks/xxx)

2. Install

git clone https://github.com/eabykov/monitor-monitoring.git
cd monitor-monitoring
go build -o monitor-monitoring .

3. Configure Endpoints

Create config.yaml:

endpoints:
  - url: https://api.github.com
    type: http
    method: GET
    expected_status: 200

4. Set Environment Variables

Telegram:

export TELEGRAM_BOT_TOKEN="123456789:ABC-DEF1234ghIkl-zyx57W2v1u123ew11"
export TELEGRAM_CHAT_ID="-1001234567890"

Slack:

export PRIMARY_NOTIFIER="slack"
export SLACK_WEBHOOK_URL="https://hooks.slack.com/services/YOUR/WEBHOOK/URL"

Discord:

export PRIMARY_NOTIFIER="discord"
export DISCORD_WEBHOOK_URL="https://discord.com/api/webhooks/YOUR/WEBHOOK/URL"

Mattermost:

export PRIMARY_NOTIFIER="mattermost"
export MATTERMOST_WEBHOOK_URL="https://mattermost.example.com/hooks/YOUR_WEBHOOK_ID"

With Fallback:

export PRIMARY_NOTIFIER="telegram"
export FALLBACK_NOTIFIER="slack"
export TELEGRAM_BOT_TOKEN="your_telegram_token"
export TELEGRAM_CHAT_ID="your_chat_id"
export SLACK_WEBHOOK_URL="your_slack_webhook"

5. Run

./monitor-monitoring

Configuration

Environment Variables

Variable	Default	Required	Description
PRIMARY_NOTIFIER	telegram	No	Primary notification channel: telegram, slack, discord, mattermost
FALLBACK_NOTIFIER	(empty)	No	Fallback notification channel if primary fails
TELEGRAM_BOT_TOKEN	-	If using Telegram	Bot token from @BotFather
TELEGRAM_CHAT_ID	-	If using Telegram	Chat/channel/group ID for notifications
SLACK_WEBHOOK_URL	-	If using Slack	Incoming webhook URL
DISCORD_WEBHOOK_URL	-	If using Discord	Webhook URL
MATTERMOST_WEBHOOK_URL	-	If using Mattermost	Incoming webhook URL
CHECK_INTERVAL	60s	No	Interval between check cycles
REQUEST_TIMEOUT	10s	No	HTTP request timeout
RETRY_DELAY	3s	No	Delay before retrying failed check
FAILURE_THRESHOLD	2	No	Consecutive failures before alerting
NOTIFY_BATCH_WINDOW	40s	No	Maximum wait time before sending batch
MAX_BATCH_SIZE	50	No	Maximum events per notification batch
MAX_CONCURRENT_CHECKS	20	No	Maximum parallel checks
MAX_RESPONSE_BODY_SIZE	524288	No	Max HTTP response body size (bytes)
DNS_TIMEOUT	5s	No	DNS query timeout
TCP_TIMEOUT	8s	No	TCP connection timeout
CONFIG_PATH	config.yaml	No	Path to YAML configuration
MONITOR_HOSTNAME	(auto-detected)	No	Hostname shown in notifications

YAML Configuration (config.yaml)

HTTP/HTTPS Monitoring

endpoints:
  # Basic HTTP check
  - url: https://example.com
    type: http                    # Optional (default: http)
    method: GET                   # Optional (default: GET)
    expected_status: 200          # Optional (default: 200)
    
  # API with authentication
  - url: https://api.example.com/health
    type: http
    method: GET
    expected_status: 200
    headers:
      Authorization: Bearer your-token
      Accept: application/json
      
  # POST endpoint
  - url: https://api.example.com/webhook
    type: http
    method: POST
    expected_status: 201

Supported HTTP methods: GET, POST, PUT, DELETE, HEAD, PATCH, OPTIONS

DNS Monitoring

endpoints:
  # A record check
  - type: dns
    host: example.com
    record_type: A                # Required: A, AAAA, or CNAME
    
  # A record with validation
  - type: dns
    host: api.example.com
    record_type: A
    expected: 192.168.1.100       # Optional: validate specific IP
    
  # IPv6 AAAA record
  - type: dns
    host: ipv6.example.com
    record_type: AAAA
    expected: 2001:db8::1
    
  # CNAME record
  - type: dns
    host: www.example.com
    record_type: CNAME
    expected: example.com

Supported record types: A (IPv4), AAAA (IPv6), CNAME

TCP Port Monitoring

endpoints:
  # Database connection
  - type: tcp
    host: db.example.com
    port: 5432
    
  # Alternative format
  - type: tcp
    address: "redis.example.com:6379"
    
  # HTTPS port
  - type: tcp
    host: web.example.com
    port: 443

Complete Example

endpoints:
  # Website
  - url: https://www.company.com
    type: http
    
  # API health
  - url: https://api.company.com/health
    type: http
    headers:
      Authorization: Bearer monitoring-token
      
  # Database
  - type: tcp
    host: prod-db.company.com
    port: 5432
    
  # DNS
  - type: dns
    host: company.com
    record_type: A
    expected: 203.0.113.10
    
  # Email server
  - type: tcp
    host: smtp.company.com
    port: 587

Docker Deployment

Dockerfile:

FROM golang:1.25-alpine AS builder
WORKDIR /app
COPY . .
RUN go build -o monitor-monitoring .

FROM alpine:latest
RUN apk --no-cache add ca-certificates
WORKDIR /root/
COPY --from=builder /app/monitor-monitoring .
COPY config.yaml .
CMD ["./monitor-monitoring"]

docker-compose.yml:

services:
  monitor:
    build: .
    environment:
      - TELEGRAM_BOT_TOKEN=${TELEGRAM_BOT_TOKEN}
      - TELEGRAM_CHAT_ID=${TELEGRAM_CHAT_ID}
    volumes:
      - ./config.yaml:/root/config.yaml
    restart: unless-stopped

Systemd Service

Create /etc/systemd/system/monitor-monitoring.service:

[Unit]
Description=Monitor Monitoring Service
After=network.target

[Service]
Type=simple
User=monitor
WorkingDirectory=/opt/monitor-monitoring
ExecStart=/opt/monitor-monitoring/monitor-monitoring
Restart=always
RestartSec=10
Environment="TELEGRAM_BOT_TOKEN=your_token"
Environment="TELEGRAM_CHAT_ID=your_chat_id"
MemoryMax=256M
CPUQuota=10%

[Install]
WantedBy=multi-user.target

Enable and start:

sudo systemctl daemon-reload
sudo systemctl enable monitor-monitoring
sudo systemctl start monitor-monitoring

Troubleshooting

No notifications received:

• Verify bot token and chat ID are correct
• Ensure bot is added to the channel/group as administrator
• Check logs for notification errors
• Test webhook URLs manually with curl

High memory usage:

• Reduce MAX_CONCURRENT_CHECKS
• Decrease MAX_RESPONSE_BODY_SIZE
• Lower MAX_BATCH_SIZE

Frequent false positives:

• Increase REQUEST_TIMEOUT
• Increase FAILURE_THRESHOLD
• Check network connectivity

Missing alerts:

• Verify NOTIFY_BATCH_WINDOW isn't too long
• Check notification queue isn't full
• Review logs for dropped events