What is Synology Hybrid RAID (SHR)? An Easy Guide

The adaptable and automated Synology Hybrid RAID (SHR) configuration mechanism was created especially for Synology NAS devices.

It simplifies the storage management process by allowing the combination of drives with different capacities and manufacturers without the full constraints of traditional RAID setups.

This capability makes SHR particularly beneficial for maximizing storage efficiency and performance. SHR, built on Linux RAID technology, is easy to use, making it great for beginners.

It also offers options for experienced users who like manual setups. Whether you need more storage or want to protect your data, SHR adjusts to different needs, making it a flexible choice for managing your files.

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How Does Synology Hybrid RAID (SHR) Work?

Synology Hybrid RAID (SHR) enhances data management by dividing disks into multiple partitions, allowing efficient use of storage.

Flexible Disk Usage with SHR

Unlike traditional RAID, SHR combines parts of disks rather than entire disks; ensuring data is spread across drives for better security and performance.

Example: Comparing SHR and RAID 5

Scenario with Four 1 TB Disks: Both SHR and RAID 5 reserve one disk for backup, providing 3 TB of usable space.
Adding a 3 TB Disk: RAID 5 treats the 3 TB disk as a 1 TB disk, but SHR uses the full 3 TB capacities.
Replacing a Second Disk: SHR increases total available space to 5 TB, while RAID 5 remains limited to 3 TB.
Efficient Adaptation to Larger Disks: SHR dynamically adjusts to larger disk sizes, offering superior storage flexibility and efficiency compared to traditional RAIDs.

Features of Synology Hybrid RAID (SHR)

Here are some key features of Synology Hybrid RAID (SHR) that can help you determine if it’s the right data storage solution for you:

Flexible Drive Compatibility: SHR lets you combine drives of different sizes into one storage array.
Full Capacity Use: It recognizes each drive’s full capacity to maximize the storage space available for redundancy.
Increased Storage Potential: You can easily expand your storage by adding larger drives to the array.
Enhanced Adaptability: SHR adapts efficiently as you add bigger drives, helping you get the most out of your storage setup.

How to Increase SHR Storage Space?

To increase the storage space in an SHR storage pool, you have two options: either replace existing drives with larger ones or add new drives.

Replace with Larger Drives

Swap out each drive one at a time.
Use the Storage Manager tool to fix the storage pool after each replacement.
Ensure that the new drives are compatible.

Add Additional Drives

Put new drives into any available slots.
Include these drives in your storage pool.
Confirm that these drives are suitable. For more detailed instructions, look up the help articles for DSM 7 and DSM 6.2.

Is Synology Hybrid RAID (SHR) Fault Tolerant?

No-Fault Tolerance

An SHR storage pool with just one drive does not provide fault tolerance.

One-Drive Fault Tolerance

To have a fault tolerance of one drive, you need at least two drives in your SHR storage pool. If you start with a pool that has only one drive, you can add another to achieve one-drive fault tolerance, similar to RAID 1.

Two-Drive Fault Tolerance

To handle two drive failures, you need at least four drives in an SHR-2 storage pool. If your pool is currently SHR-1, which tolerates one drive failure, you can switch to SHR-2 by using the “Change RAID Type” option.

Synology Hybrid RAID (SHR) Recovery

Synology Hybrid RAID (SHR) offers several advantages over traditional RAID setups available on most Synology NAS models:

1: SHR allows you to combine hard drives from different manufacturers, with varying speeds and capacities, in one setup.

2: It provides more usable storage space compared to traditional RAIDs because only the capacity of one of the largest drives is used for redundancy.

3: SHR guards against data loss in the event of a single drive failure (or two drives with SHR-2).

4: You can add new drives to an SHR setup anytime without needing to do complex calculations beforehand.

However, SHR does operate at a slightly slower speed than traditional RAID. Additionally, its complex structure can make recovering critical files challenging in case of data loss.

When Do You Need Synology SHR Recovery?

Synology Hybrid RAID (SHR) is based on RAID technology and can face similar issues, making your files inaccessible. Here’s when you might need recovery:

Configuration Issues: Loss of power or a mistake during a rebuild can cause incorrect settings, leading to problems.
File System Corruption: Software crashes, malware, power failures, and incorrect shutdowns can corrupt the file system.
Software Errors: Bugs in the firmware or operating system can make partitions or the entire storage unit inaccessible.
User error: Data loss may result from inadvertent deletion, formatting, reinstallation, or setup errors.
Physical Damage: Damage to the NAS box or its disks might cause complete data loss. NAS systems are designed to handle up to two drive failures, depending on the setup. Signs of trouble include unrecognized disks, a missing user interface, error alerts, unusual indicator lights, and odd sounds like beeping or ticking.

Pros of Synology Hybrid RAID (SHR)

Fast and easy to set up.
Flexible scaling as you can add more drives over time.
Allows mixing different sizes of drives, optimizing storage use while maintaining redundancy for one disk.
Drives from an SHR system can be moved to another Synology device that supports SHR; the new device will recognize the volumes and data.
If a drive fails, Synology can still access the data, though at a slower pace, until the drive is replaced.

Cons of Synology Hybrid RAID (SHR)

Speeds are comparable to RAID 5 and 6 but slightly slower than traditional RAID systems.
Drives need to be formatted when moved from an SHR RAID to a non-SHR system.

Conclusion

Synology Hybrid RAID (SHR) is an innovative solution for flexible and efficient data storage on Synology NAS devices. Its ability to utilize drives of different capacities and adapt dynamically to larger disks makes it a superior choice over traditional RAID systems.

With features like fault tolerance, easy scalability, and user-friendly setup, SHR simplifies storage management for both novices and experienced users.

Despite minor speed limitations, its versatility and enhanced storage potential make SHR an excellent option for modern data management needs.

Frequently Asked Questions

What is Synology Hybrid RAID (SHR)?

SHR is a flexible storage system for Synology NAS devices that allows you to mix drives of different sizes and maximize storage space while keeping your data safe.

How is SHR different from traditional RAID?

Unlike traditional RAID, SHR can use the full capacity of larger drives and allows you to combine drives of various sizes, making them more efficient and easier to manage.

Can I add more drives to an SHR setup later?

Yes, you can easily add more drives or replace smaller ones with larger ones to increase your storage space without losing data.

Does SHR protect against data loss?

Yes, SHR provides fault tolerance. With at least two drives, it can handle the failure of one drive. SHR-2 can handle two drive failures with four or more drives.