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The 7-Minute Guide to Mirror Backup: What You Need to Know

February 3, 2020

What if your computer crashed tomorrow?

Would your data be safe from harm, or would you be scrambling to the nearest repair shop hoping your documents and files were somehow still there?

No matter if your data is personal or professional, you would never want to wake up one day to find that it’s gone forever. If you don’t take the time to backup your data, you could lose it all (precious photos and videos, important business contracts, maybe even your family records) in an instant.

There are a variety of ways you can protect your data from hackers, corruption, and sudden natural disasters. From storing files in the cloud to having your own personal external hard drive, all backup methods are unique, and while one may not work for you, another could be the perfect solution.

One of the most convenient backup methods is a mirror backup.

Mirroring your data has become more and more popular in the world of information technology. Follow along as we dive deeper into what mirror backup is, its pros and cons, how it differs from other methods, and when it’s most useful.

Mirror backup: explained

Although a mirror backup is similar to a full backup, a mirror backup creates an identical “mirror image” that backs up everything on the computer rather than just the files and folders you select when running a full backup.

This means that all of your files (including personal documents, the operating system, apps, boot information, hidden files, your settings and preferences, and any installed software) are consolidated to a few files instead of dozens.

Running a mirror backup not only captures your individual files but everything you need to get your system running smoothly in the event of a crash.

And while the most common backup types are full backup, incremental backup, and differential backup, this doesn’t mean that a mirror backup (or any other type) isn’t useful. In fact, many people prefer using this method because it doesn’t take as long as others.

Related: Want to learn more about the different types of backup? Click through to discover the difference between incremental and differential backup and how to choose the right one for you.

Because mirror backups are usually smaller than other types, they’re usually stored on personal external hard drives, network drives, and sometimes even DVD or Blu-ray discs. Many people utilize mirror backups because the process of running the backup is rather quick.

The first time you run a mirror backup will be the longest time you’ll ever have to wait. Every time after that, your backup times will get shorter and shorter because they are only backing up the new and/or modified files.

size of mirror backup over time


In addition to mirror backup, there is a slew of backup software options to choose from. These tools offer protection for data by copying it from servers, databases, desktops, laptops, and other devices in case user error, corruption, or natural disasters render a business’ critical data inaccessible.

Check out the best ranking backup software to find your perfect fit.

Many backup services offer a mirror backup with a 30-day delete, meaning that when you delete a file from your source (whether on purpose or on accident), that file will be stored on the server for a minimum of 30 days before it is deleted forever. Because there is some risk of accidental data loss when running mirror backups, this feature strengthens the safety of using this method and reassures users that, as long as they check up on the backup monthly, their data will be safe.

What makes mirror backups different?

When talking about data security and backing up your data, it’s easy to get confused. There are dozens of methods, lots of jargon, and too many acronyms to remember.

For the sake of this article, we’ll be talking about the difference between mirror backups, regular backups, and disk cloning.

Mirror backup vs. backup

When you think of a “regular” backup, you may imagine dragging files and folders onto a hard drive so that you can access them whenever you want. You may imagine plugging the hard drive into your computer to access a certain file in one of your backed up folders. For a lot of people, this is as far as backing up their data will go. This type is usually referred to as a traditional backup.

A traditional backup is a copy of your data. If your computer is damaged, having that backup of your photos, videos, music, etc. keeps all of it from being lost forever. But, while the files and folders you backed up are protected, you will have to reinstall the operating system, reset all of your preferences, and reload all of the programs you use to get everything back to normal.

This is precisely how mirror backup is different.

Instead of choosing what you want to backup, running a mirror backup will take everything on your computer and make an exact copy. By consistently creating mirror backups of your computer, you’ll be able to restore your system and all of the preferences you previously made.

Mirror backups vs. disk cloning

Backup jargon is tricky and a lot of terms seem to be used interchangeably. This is the case for disk cloning and mirror backup. Although disk cloning also creates an exact copy of your hard drive, it’s not the same as a mirror backup.

A mirror backup will create one compressed file that’s used to recover data after a disaster. You’ll be able to restore your computer just as you had it (settings and all).

When you clone a disk, you copy the data of one hard drive to another hard drive. Both the source and the new hard drive will contain the exact same data. Cloning allows you to transfer data from one drive to another rather than transferring data from a drive to your computer.

In a lot of ways, a mirror backup is essentially the same thing as disk cloning (both copy everything from the computer). Disk cloning allows you to transfer data from one hard drive to another, while mirror backups store your data and compress it to just a few small files for when you’re ready to access it again.

Because disk cloning is time-consuming and allows for no mistakes, it’s usually a one-time process that transfers data from one drive to another. It’s rarely used as a continuous backup method.

The pros and cons of mirror backup

Just like any data protection method, there are good and bad things about using mirror backup. Below, we’ve outlined the advantages and disadvantages you can run into when using this method.

Pros of mirror backup

For starters, mirror backup is the fastest backup type and creates clean backups with no old or outdated files. This means that you won’t have to go into the backup and delete obsolete files, making the process quick and efficient. A mirror backup creates a quick summary of your computer and keeps it safe until you want to access it later on.

Additionally, this backup method takes up less space on your drive, and because of its small size, it can be stored on a drive you actively use.

You are also able to recover your data quickly and even access individual files rather than having to load the entire backup.

Cons of mirror backup

There are a few things you need to consider before you jump into mirror backup. For example, password protection isn’t possible, and you won’t be able to track different versions of your files.

One of the biggest risks you take is the chance of data deletion. There’s the chance that files may be deleted accidentally (through sabotage, viruses, or malware). If a file is deleted from the source, it will also be deleted from the backup, and if no one checks to see that all the files are still intact before running a backup, you’ll lose that file forever.

pros and cons of mirror backup


Mirror backups should be used with caution. Even if you don’t end up using this method, it’s a good rule of thumb to always have multiple copies of your data stored on separate devices in case of damage.

It’s common practice to follow the “3 in 1 backup” rule. This is where you store your data in three places, on two types of storage, and with one copy kept off-site. If one copy is damaged, you’ll still have two copies to restore from.

When is a mirror backup useful?

From everything we’ve already discussed, creating a mirror image backup may be the right method for you depending on what you’re trying to achieve.

A mirror backup is useful to have if you want to be sure that your entire hard drive can be restored (as it is) sometime in the future. This includes all of your documents, programs, apps, and photos, even the files laying in the abyss of your trash can.

Mirror backup is also useful if you’ve installed a lot of programs. If you use your computer for work, odds are you’ve downloaded a fair number of apps and programs over the years. If you want to make sure you don’t lose them (or have to reinstall them if your computer crashes), a mirror backup is handy. If anything were to damage your existing drive, you’d be able to restore your data on a new one and have everything as it was.

Storing your mirror backup

When you restore your data, you’ll want to know your backup is reliable and fast. Where you store your backup will have an effect on both of these outcomes.

Backing up your data to an external hard drive or network-attached storage will protect your data more than it would if you backed up to your computer’s hard drive. This might be convenient, but it ends in disaster if your disk fails.

Additionally, a physical copy is a good start but having an off-site copy is even better. A natural disaster like a fire or flood can hit and render your data useless if it damages your hard drive. Having your data stored somewhere off-site (like the cloud) will ensure that it’s safe even if the drive is ruined.

Are you seeing double?

At the end of the day, you want to find a backup method that works for you. One that fits into your schedule and one you have enough storage space for. If you think mirror backups may be the solution for you, give it a try.

The first step to protecting your data is doing research to find your best option. It’s clear that you’re well on your way to ensuring you’re safe from any potential threat.

Already been affected by a data loss event? Disaster recovery (DR) solutions help businesses quickly and efficiently recover software, settings, and data to its original state. Browse the best disaster recovery software to find a solution for you.

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