What is a Hot Spare and its Peculiarities of Usage

Theo Lucia

Jan 27, 2024 • Filed to: Windows Computer Solutions • Proven solutions

Even though our progress as a technologically advanced nation knows no bounds, we are still many steps behind. The devices and systems under our use can undergo damage and become unfunctional in seconds. To handle such circumstances, Hot Spare is introduced as a backup plan to become operational.

Fortunately, this article reflects how Hot Spare can be configured and its peculiarities in usage. Being used as standby disk drives, a Hot Spare has its pros and cons. So, without delaying this any longer, let us get right into it.

Part 1: What is Hot Spare?

The first question that comes into a layman's mind is what is Hot Spare, and how does it even work? People who use these drivers in their systems still do not know enough. Therefore, before jumping onto the configuration steps and peculiarities of Hot Spare, let us embark on a journey of awareness regarding this operative component of the computer.

A Hot Spare is a standby device and a backup plan for your computers if your PC's primary component fails to work, goes offline, or gets faulty. They work automatically by repairing the degraded storage pool and replace a failed drive. Called an operative component and a part of the working system, Hot Spare can be different devices to help cope with the failure that occurred in the system.

Therefore, it could be hard disk drives, network printers, A/V switches, or power supplies. As they can be used for both hardware and software backup, this peculiar backup device is called "Hot" as it is always turned on in unforeseen circumstances. Moving on, Hot Spares are responsible for protecting storage pools with a significant criterion.

For starters, the size of the Hot Spare drive must be equal to the size of the smallest drive in the storage pool. Secondly, the RAID type of pool has to support the drive fault tolerance.  A Hot Spare drive works like a charm to prevent potential data loss and increase system availability during the exchange process.

Now, the next question revolves around the working process of the Hot Spare device. This device RAID only works when it is in an array. In case of system failure, the RAID controller initiates the rebuilding procedure and replaces the faulty disk with Hot Spare. Moreover, a Hot Spare drive can be utilized for any failed disk in the storage array if it is not allocated for a specific volume group.

However, the Hot Spare device must offer certain traits and characteristics that are identical to the protected disk. Therefore, you might want to install multiple Hot Spares to enhance data availability and data protection. 

Part 2: How to Set up and Configure Hot Spare?

We hope that the user has a clear and workable knowledge of how Hot Spare works after the above section. Moving on, let us shift our focus to the procedure of its configuration and set up. It is important to keep in mind that when a drive is assigned as a Hot Spare component, the data will be erased. Hence, make sure that the drive has no necessary data.

Unlike other hardware and software devices, the connection process is not as easy as it sounds. However, to make it look effortless for you, we have designed this section. Let us first glance at "how to step up Hot Spare?" and then move on to its configuration process.

1. The first step is to tap on “Manage.” A dialogue box pops up. This box shows the status of the Hot Spare device with each storage pool and the drivers available. If you are unaware of what the status might display, have a look below:

Assigned Status shows that the storage pool is safeguarded by one Hot Spare drive.

Available Status displays drives to protect the storage pool, but no Hot Spare device is allocated to them.

Not Available Status reveals that there are no Hot Spare drives to safeguard the storage pool.

2. To assign a Hot Spare device based on Available Status, tick mark the box beside the drive you want to allocate as a Hot Spare device.
3. Now, tap on “Apply” so that settings can be saved.

Now that we know how to set up Hot Spare, let us find out the procedure for Hot Spare settings to a storage pool.

1. For starters, click on “Configure.” A “Storage Pool” tab will appear. From there, the user will find the listing of the storage pool that has a chance to be protected by Hot Spare drives.
2. If you untick any boxes, the storage pools next to them will not be repaired automatically by Hot Spare drives in case of sudden system failure.
3. Moving on, from the “Cross device Hot Spare" tab, you can permit the Hot Spare drive from one device to repair a degraded RAID present on another device.
4. In the last step, hit “OK” and save the settings.

Part 3: Peculiarities of Using Hot Spare

This section will overlook the peculiarities of incorporating the usage of Hot Spare drive in our systems. From the outlook of using Hot Spare and the range of problems it solves, this section comes off as useless and unrequired. Even though Hot Spare drive minimizes the degraded array state and provides us with an effortless backup plan in seconds, we might not be looking at the big picture here.

The sole purpose of an excessive array of cheap and inexpensive disks is to ensure that no loss of data occurs when unforeseen circumstances such as a drive failure and the operation process are continued. However, as far as Hot Spare functionality is concerned, while it rebuilds RAID, the likelihood of an additional drive failure is enhanced to multiple folds.

If your array exhibits a degraded state due to driving failure, we suggest performing the following procedure carefully.

1. The first and foremost step is to perform a full data backup.
2. After that, ensure that the backed-up data is stable and if the data restoration mechanism is operational.
3. The next concern is to identify the source and occurrence of the problem—for instance, a faulty disk drive.
4. Now, it is important to replace the failed disk drive with a new one. However, if the replaced hard drive had been used in another RAID array, you might want to delete any remaining metadata on it.
5. Now, initiate the process of RAID rebuilding.

As mentioned in the steps above, the RAID rebuilding is the fifth step. However, when you wish to take advantage of Hot Spare drive, it completely ignores the first two critical steps and jumps to identifying the problem source until rebuilding. Due to this glitch, the protection of data is not ensured.

Therefore, you might want to question yourself today if you care about the safety and integrity of your data or need an immediate rebuild after a component failure. 

Wrapping Up

The article covered the basics of Hot Spare, how it works, and the pros that make it usable in the market. Moreover, there is a reflection of comprehensive steps to set up and configure it in your system. By the end of this article, the peculiarities of using Hot Spare were described. You might want to rethink your decision about incorporating the usage of Hot Spare if data protection is your main concern.

Frequently Asked Questions (FAQs)

1. Is a Hot Spare needed in Raid 10?

A 16-or-24-drive has two spare drivers, while RAID 10 array permits 12-20 drives in a multiple of four drivers. Therefore, it is a less flexible replacement for Hot Spare.

2. Which is better: "Raid 5 + Hot Spare" or "Raid 6?”

If you are looking for safety, you might want to shift your focus to Raid 6. The reason behind this is that it can survive two drivers failing simultaneously. However, you are a big fan of performance, go with “Raid 5+Hot Spare.” It is because the write performance works magically when the array is not in a degraded state.

If you are concerned about power consumption, "Raid 5+ Hot Spare" has to be your choice if your controller keeps the spare drive switched off until required.

3. What is the difference between Hot Space and Cold Space?

The Cold Space serves as a component such as a hard disk. Although it is already in your system still requires manual intervention if a component failure occurs. The "Hot Spare," on the other hand, engages automatically and works as a backup plan.