🔰 What is Scrutiny? A Beginner's Explanation

Scrutiny is an open-source tool for checking the "health" of hard drives and SSDs. It collects S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology) information and displays it in intuitive graph format on a web browser, allowing even beginners to easily understand disk status without specialized knowledge.

Key information you can check with Scrutiny includes:

• Power-on hours of the disk: cumulative time since startup.
• Temperature history: current temperature and past fluctuations.
• History of errors and warnings: early detection of abnormal signs to reduce the risk of data loss.

In this guide, we'll use the master-omnibus version, which includes a bundled database (InfluxDB). This eliminates the need to set up a separate database, making it easy for beginners to get started.

🤔 Installing Scrutiny in a Synology DSM Environment

Synology NAS runs on its own OS called "DSM," which is based on Linux. By installing the Docker package on DSM, you can easily run Scrutiny as a container. However, you'll need to adjust settings to fit Synology's specific directory structure (e.g., /volume1/docker).

🛠 What You'll Need for Installation

To run Scrutiny with Docker, you'll need to prepare the following three elements:

1. Prepare Storage Folder: Create a directory to store Scrutiny's configuration files and collected data (recommended path: /volume1/docker/scrutiny).
2. Identify Monitored Disks: Find the Linux device names (e.g., /dev/sda) for the HDD/SSD you want to monitor.
3. Create docker-compose.yml File: Create the "blueprint" file that defines the Scrutiny container's startup settings.

📁 Step ①: Create Storage Folder

Create a folder where Scrutiny's configuration files and InfluxDB data will be persistently stored. On Synology NAS, Docker-related data is typically placed under /volume1/docker.

Copymkdir -p /volume1/docker/scrutiny/influxdb

Executing this command will create the following directories:

• /volume1/docker/scrutiny/: For Scrutiny's overall configuration files.
• /volume1/docker/scrutiny/influxdb/: For time-series data like S.M.A.R.T. information.

🔍 Step ②: Identify Disks to Monitor

To specify which HDD/SSD Scrutiny should monitor, you need to accurately know their Linux "device names" (e.g., /dev/sda). You can check this using the following commands.

Method A: Check device information with `lsblk` command

Copylsblk -o NAME,MODEL,SIZE,TYPE,MOUNTPOINT

Example Output:

NAME        MODEL           SIZE TYPE MOUNTPOINT
sda         TOSHIBA HDWD130 4T   disk
sdb         WDC WD40EZRX    4T   disk

In the example above, the disks to be monitored are /dev/sda and /dev/sdb.

Method B: Scan S.M.A.R.T. compatible disks with `smartctl` command

Copysmartctl --scan

Example Output:

/dev/sda -d sat # ATA device
/dev/sdb -d sat # ATA device

Note: For NVMe SSDs, the device name might look like /dev/nvme0n1.

📝 Step ③: Create `collector.yaml` File

This file configures which disks Scrutiny should monitor. The example below is for monitoring two SATA disks (/dev/sda, /dev/sdb).

Copycat <<EOF > /volume1/docker/scrutiny/collector.yaml
version: 1
host:
  id: ""

devices:
  - device: /dev/sda
    type: 'sat'
  - device: /dev/sdb
    type: 'sat'
EOF

Configuration Points:

• type: 'sat': Apply this for SATA connected HDDs/SSDs.
• type: 'nvme': Specify this for NVMe connected SSDs.
• If you want to add more disks to monitor, add entries in the same format under the devices section.

⚙️ Step ④: Create `docker-compose.yml` File

This is the "blueprint" file that defines the startup settings for the Scrutiny container. Below is a basic example configuration.

Copycat <<EOF > /volume1/docker/scrutiny/docker-compose.yml
version: '3.8'

services:
  scrutiny:
    container_name: scrutiny
    image: ghcr.io/analogj/scrutiny:master-omnibus
    cap_add:
      - SYS_RAWIO
      - SYS_ADMIN
    ports:
      - 6090:8080/tcp
      - 8086:8086/tcp
    volumes:
      - /run/udev:/run/udev:ro
      - /volume1/docker/scrutiny:/opt/scrutiny/config
      - /volume1/docker/scrutiny/influxdb:/opt/scrutiny/influxdb
    devices:
      - /dev/sda:/dev/sda
      - /dev/sdb:/dev/sdb
    environment:
      - COLLECTOR_CRON_SCHEDULE=0 23 * * *
      - TZ=Asia/Bangkok
    security_opt:
      - no-new-privileges:true
    restart: unless-stopped
EOF

Configuration Points:

• /run/udev:/run/udev:ro: Required to obtain disk information in read-only mode.
• TZ=Asia/Bangkok: This is the timezone setting. Change it according to your location (e.g., Asia/Tokyo if you are in Japan).
• devices: List all the same monitored disks specified in collector.yaml.
• COLLECTOR_CRON_SCHEDULE: Specifies the data collection timing in cron format. Defaults to 11 PM daily.

🚀 Step ⑤: Start Scrutiny

Execute the following commands to start the Scrutiny container in the background.

Copycd /volume1/docker/scrutiny
docker-compose up -d

🌐 Step ⑥: Verify Operation

Open your web browser and go to the following URL:

http://[NAS_IP_Address]:6090

If Scrutiny's dashboard appears and you can see your monitored disk temperatures and S.M.A.R.T. information, the installation was successful!

How to check logs (for troubleshooting):

Copydocker logs scrutiny

❓ Frequently Asked Questions and Configuration Tips

Why mount /run/udev:/run/udev:ro?

Linux's "udev" is a system that manages device information, such as disks. For Scrutiny to correctly recognize disks and read S.M.A.R.T. information, it needs to mount this /run/udev directory into the container in read-only mode (ro). This allows Scrutiny to reference device information without affecting the actual devices.

Why specify TZ=Asia/Bangkok?

Scrutiny timestamps the collected S.M.A.R.T. data. If you don't specify a timezone, the server's default timezone will be used, which can lead to time discrepancies in the web UI's graph display. It's crucial to specify the correct timezone for your region (e.g., Asia/Tokyo for Japan) to ensure accurate data logging and display.

⚠️ Common Issues and Solutions

🎯 Conclusion

Scrutiny is an incredibly useful tool that allows even beginners to easily monitor the health of their HDDs and SSDs. If you have a Synology DSM or Docker-enabled Linux environment, you can smoothly install it by following the steps in this guide. Once set up, Scrutiny will automatically check your disk health daily, acting as your "storage health partner."

Adjust the disk names and timezone to match your NAS environment, and secure the peace of mind for your valuable storage!