Monitor Monitoring

Lightweight monitoring tool. Checks HTTP/HTTPS endpoints, DNS records, and TCP ports. Sends alerts via Telegram, Slack, Discord, or Mattermost.

Features

• Multi-protocol — HTTP/HTTPS, DNS (A/AAAA/CNAME), TCP
• Smart alerting — configurable failure threshold + automatic retry before alerting
• Batch notifications — anti-spam window groups events before sending
• Fallback notifier — secondary channel if primary fails
• Graceful shutdown — SIGTERM flushes pending notifications and sends shutdown alert
• 12-factor config — all settings via environment variables

Quick Start

git clone https://github.com/ML-ZoneReaper/monitor-monitoring.git
cd monitor-monitoring
CGO_ENABLED=0 go build -ldflags="-s -w" -o monitor-monitoring .

Create config.yaml (see Configuration), then run:

export TELEGRAM_BOT_TOKEN="..."
export TELEGRAM_CHAT_ID="..."
./monitor-monitoring

Notification Channels

Set PRIMARY_NOTIFIER (default: telegram) and optionally FALLBACK_NOTIFIER.

Channel	Required env vars
telegram	TELEGRAM_BOT_TOKEN, TELEGRAM_CHAT_ID
slack	SLACK_WEBHOOK_URL
discord	DISCORD_WEBHOOK_URL
mattermost	MATTERMOST_WEBHOOK_URL

Get Telegram credentials:

• Bot token: message @BotFather, send /newbot
• Chat ID: add @userinfobot to your group, or call https://api.telegram.org/bot<TOKEN>/getUpdates

Example with fallback:

export PRIMARY_NOTIFIER="telegram"
export FALLBACK_NOTIFIER="slack"
export TELEGRAM_BOT_TOKEN="..."
export TELEGRAM_CHAT_ID="..."
export SLACK_WEBHOOK_URL="..."

Environment Variables

Variable	Default	Description
PRIMARY_NOTIFIER	telegram	Primary channel: telegram, slack, discord, mattermost
FALLBACK_NOTIFIER	—	Fallback channel if primary fails
TELEGRAM_BOT_TOKEN	—	Telegram bot token
TELEGRAM_CHAT_ID	—	Telegram chat/group/channel ID
SLACK_WEBHOOK_URL	—	Slack incoming webhook URL
DISCORD_WEBHOOK_URL	—	Discord webhook URL
MATTERMOST_WEBHOOK_URL	—	Mattermost incoming webhook URL
CHECK_INTERVAL	60s	Interval between check cycles
REQUEST_TIMEOUT	10s	HTTP request timeout
RETRY_DELAY	3s	Delay before retry on failed check
FAILURE_THRESHOLD	2	Consecutive failures before alert
NOTIFY_BATCH_WINDOW	40s	Max wait before sending a batch
MAX_BATCH_SIZE	50	Max events per notification
MAX_CONCURRENT_CHECKS	20	Max parallel checks
MAX_RESPONSE_BODY_SIZE	524288	Max HTTP response body to drain (bytes)
DNS_TIMEOUT	5s	DNS query timeout
TCP_TIMEOUT	8s	TCP connection timeout
CONFIG_PATH	config.yaml	Path to YAML config file
MONITOR_HOSTNAME	(auto)	Hostname shown in notifications

YAML Configuration

HTTP/HTTPS

endpoints:
  - url: https://example.com              # required
    type: http                            # optional, default: http
    method: GET                           # optional, default: GET
    expected_status: 200                  # optional, default: 200
    headers:                              # optional
      Authorization: Bearer token

Any valid HTTP method is accepted (GET, POST, PUT, DELETE, HEAD, PATCH, OPTIONS, etc.).

DNS

endpoints:
  - type: dns
    host: example.com
    record_type: A                        # required: A, AAAA, or CNAME
    expected: 192.0.2.1                   # optional: validate specific value

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

TCP

endpoints:
  - type: tcp
    host: db.example.com
    port: 5432

  # or using address directly
  - type: tcp
    address: "redis.example.com:6379"

Docker

FROM golang:1.26-alpine AS builder
WORKDIR /app
COPY . .
RUN CGO_ENABLED=0 go build -ldflags="-s -w" -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: .
    env_file: .env
    volumes:
      - ./config.yaml:/root/config.yaml
    restart: unless-stopped

Systemd

# /etc/systemd/system/monitor-monitoring.service
[Unit]
Description=Monitor Monitoring
After=network.target

[Service]
Type=simple
User=monitor
WorkingDirectory=/opt/monitor-monitoring
ExecStart=/opt/monitor-monitoring/monitor-monitoring
Restart=always
RestartSec=10
EnvironmentFile=/opt/monitor-monitoring/.env
MemoryMax=256M
CPUQuota=10%

[Install]
WantedBy=multi-user.target

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

Troubleshooting

Symptom	Fix
No notifications	Check token/webhook URL; verify bot is admin in Telegram group
False positives	Increase FAILURE_THRESHOLD or REQUEST_TIMEOUT
Delayed alerts	Decrease NOTIFY_BATCH_WINDOW
High resource usage	Lower MAX_CONCURRENT_CHECKS and MAX_RESPONSE_BODY_SIZE
DNS checks failing	Ensure host's DNS resolver is reachable from monitoring machine