Synology NAS (Network Attached Storage) devices are known for their versatility, offering a wide array of features for data storage, sharing, and management. One feature that significantly enhances performance is the Synology SSD cache. This guide explores Synology SSD cache, its benefits, how to set it up, the importance of upgrading DiskStation Manager (DSM) versions, and how to verify if you’re running the latest DSM version.

What is Synology SSD Cache?

An SSD cache uses Solid-State Drives (SSDs) to accelerate data access on traditional Hard Disk Drives (HDDs). SSDs are much faster than HDDs due to their lack of mechanical parts, providing lower latency and higher throughput. In Synology NAS, SSD caching improves the performance of your storage pools without requiring a full SSD-only setup.

Types of SSD Cache in Synology NAS

1. Read-Only Cache:
   • Speeds up frequently accessed data by storing it in SSDs.
   • Improves read performance but does not affect write operations.
2. Read-Write Cache:
   • Boosts both read and write performance.
   • Requires at least two SSDs in RAID 1 for redundancy.

Benefits of SSD Cache

• Enhanced Performance: Faster data access and improved application performance.
• Cost-Effective: Combines HDDs and SSDs for performance gains without the expense of SSD-only setups.
• Scalable: Easily added or removed as needed.
• Optimized Utilization: Ensures frequently accessed data is quickly available.

When to Use SSD Cache

• High I/O Workloads: For example, virtualization, databases, or file servers.
• Mixed Storage Systems: Combining HDDs and SSDs for balanced performance.
• Repetitive Access Patterns: Ideal for applications with predictable workloads.

How to Set Up SSD Cache

Prerequisites

• A compatible Synology NAS model.
• Supported SSDs (check Synology’s compatibility list).
• An existing storage pool.

Configuration Steps

1. Install SSDs:
   • Install SSDs in the designated bays or via an adapter card like the Synology M2D17 in PCIe Slot 1.
   • Verify installation using Synology DSM.
2. Create SSD Cache:
   • Navigate to Storage Manager > SSD Cache.
   • Choose the storage pool and cache type (read-only or read-write).
   • Follow the on-screen instructions.
3. Monitor Performance:
   • Use Resource Monitor to track cache efficiency.
4. Optimize Cache:
   • Update DSM for the latest features.
   • Adjust settings as needed.

Why Upgrade DSM?

DiskStation Manager (DSM) is the operating system powering Synology NAS devices. Regular upgrades are essential for:

• New Features: Improved functionality and usability.
• Security: Patches to keep your system secure.
• Performance: Enhanced efficiency with updated algorithms.
• Compatibility: Support for new hardware and apps.
• Bug Fixes: Resolves known issues.

DSM Upgrade Steps

1. Prepare for the Upgrade:
   • Backup data using Hyper Backup.
   • Verify compatibility and system health.
2. Upgrade DSM:
   • Use the Control Panel > Update & Restore for automatic updates.
   • Perform manual updates by downloading the update file from Synology’s website.
3. Post-Upgrade Verification:
   • Test applications and review logs for errors.
   • Reconfigure settings as needed.

How to Verify DSM Version

1. DSM Interface: Navigate to Control Panel > Update & Restore to check for updates.
2. Synology Assistant: Use this tool to display the DSM version.
3. Command-Line: Run cat /etc/VERSION via SSH.
4. Mobile App: Use Synology’s DS Finder to check the version.

My Setup and Observations

I am using a DS1817+ with eight Seagate ST8000AS0002-1NA17Z 8 TB Archive HDDs, running without issues. Currently, I’m upgrading to 16 TB Western Digital WDC WD161KFGX-68AFPN0 HDDs. My SSD cache consists of two Samsung SSD 850 EVO M.2 (500 GB) drives installed using a Synology M2D17 adapter in PCIe Slot 1.

Hardware Highlights

Seagate ST8000AS0002 HDD:

• Energy-efficient archival storage.
• Reliable for long-term use.

Western Digital WDC WD161KFGX HDD:

• High-capacity Ultrastar DC HC500 series.
• Optimized for data centers with vibration resistance.

Samsung SSD 850 EVO M.2:

• Advanced 3D V-NAND technology.
• TurboWrite for faster write speeds.
• High endurance and energy efficiency.

Best Practices for SSD Cache

• Regular Maintenance: Monitor and optimize cache performance.
• Stay Updated: Enable automatic DSM updates.
• Evaluate Workloads: Periodically assess cache efficiency.
• Use Compatible Hardware: Follow Synology’s compatibility guidelines.
• Backup Data: Regularly back up to avoid data loss.

Conclusion

Synology SSD cache is a game-changer for optimizing NAS performance. Coupled with regular DSM upgrades, it ensures a reliable and high-performing system. Follow these best practices to maximize your NAS potential, enhance data security, and enjoy seamless compatibility.