Full, Incremental, Differential, and Synthetic Full Backups – Differences

Data loss always comes as a surprise to the company. With one successful data breach, companies of all sizes can lose all their data and fortune. 93% of data breach cases occur in minutes, with the companies left scrambling to figure out how the data was lost. In today’s world, data is your organization’s most prized asset, and any serious data loss incident can cause severe damage to the company. Therefore, you and your organization need a reliable backup strategy for your data to prevent unprecedented data loss.

Since not all IT organizations can support every type of backup due to network capability being different from one organization to another, it’s prudent to determine which type is the most appropriate for your business. To choose the suitable backup method, you need to take a tactical approach that may help your business achieve better data protection without requiring too much of its network. This article will discuss the different types of data backups and highlight their advantages and disadvantages.

What are Data Backups?

The practice of data backup combines techniques and solutions to ensure efficient and cost-effective backup. It involves copying or transferring data from one location to another to protect against malicious intent, natural disasters, and data accidents. Today, many kinds of data backup strategies help enterprises and organizations ensure that data is secure and that they don’t lose that critical information in a natural disaster, theft situation, or other kinds of emergency.

Your data backup strategy should reflect your IT resources, needs, and budget. While some data backup strategies look good on paper, they might be more trouble than they are worth if they don’t align with your business’s ideals. Essentially, there are four types of data backups you need to know, and they include:

  • Full backups
  • Incremental backups
  • Differential backups
  • Synthetic full backups

Knowing the proper backup for your business can be overwhelming, so we will discuss each backup type in the sections below to show their differences, advantages, and disadvantages.

Full Backups

As the name suggests, full backups involve a complete copy of all your data. They are the simplest and most common form of data backup strategy. Full backups are usually performed when providing backup solutions and may be periodized, although this depends on customer preferences.

One significant advantage of full backups is their simplicity and fast recovery time since the data is all in one place. Most companies perform a full data backup after making significant changes to the data on the storage disk, for example, a software installment or operating system upgrade. However, since each full backup will contain all the company’s essential data, it can be susceptible to unauthorized external attacks and threats. To avoid this, you can use data encryption as added security if your backup strategy supports it.

Another disadvantage of full backups is that they take up a lot of storage space and are time-consuming, which is why most organizations perform them periodically. The fast recovery times and excellent reliability of full backups somewhat outweigh its disadvantages. Full backups are also often the starting point for other backup strategies.

A full backup is perfect if you’re a small business dealing with a small amount of data. It won’t take too long to back up or eat up storage space. It would be best to consider how frequently you should do your full backups, given that they are the safest recovery option for your data and the most time-consuming and costly of all your backup options.

Some companies do full backups daily, some do them weekly, while others prefer a monthly basis or less. Your frequency of performing full backups will depend on your backup plan and needs for data security versus your time, funds, and resources.

Incremental Backups

Incremental backups only copy or transfer the data that has been changed since the last backup session. Most times, a full backup precedes an incremental backup. If you’re a large corporation dealing with large amounts of data, doing a full backup every time you need to back up your data might be challenging. It might be better to do a full backup; any succeeding backup only copies the latest data changes. One of the advantages of incremental backups is that it takes less time to copy the data and consumes less storage space.

Another advantage is that the backup process can be fast depending on the number of files you need to backup. Since you’re dealing with a smaller data set, you can run an incremental backup as many times as you want, with each backup process being an individual recovery. While incremental backups are more flexible and consume less storage space, their restoration process can be more time-consuming. You must recover the initial full backup and move through all the other backup processes you did, no matter how many.

This also means the whole backup chain is only as strong as its weakest link. So, if one of the backup files is compromised, there’s a probability you won’t get to retrieve any data. File search is also stressful since you’ll have to comb through several backup sets to find a specific file or data. If you deal with large volumes of data and don’t have time to focus on your backup process, the incremental backup strategy will be effective since it encourages fast backups and takes up less storage.

Determining when and how often to do your full backups and deciding how many previous versions of your backups you want to save is a strategic decision that should consider your budget, risk factors, time, and typical operating conditions. For instance, you could perform a full backup on Saturdays and incremental backups Sunday through Friday. It’s essential to think about your data and how often it changes.

Differential Backups

Differential backups are midway between full backups and incremental backups. They involve backing up hard drives, folders, and files created since the last or initial full backup. This means that, like incremental backups, you must perform a full backup before your differential backups. Differential backups use only two pieces of backup, the initial or latest full backup, and the most recent differential backup, to recover data.

Differential backups restore data slower and more complex than full backups but faster than incremental backups. The storage space needed for differential backup is also more when compared to an incremental backup but less than a full backup. There is a probability that you will have a failed recovery if any backup data set in your differential backup chain is compromised. Nevertheless, the differential backup will be helpful for small and medium-sized organizations that want to process large volumes of valuable data but cannot perform constant backups.

Synthetic Full Backups

Synthetic full backups combine the advantages of full and incremental backups. They leverage existing full backups and subsequent incremental backups to create an updated full backup.

All the differential or incremental backups will start at this latest point without relying on source machines. This eliminates the need to transfer large volumes of data during each backup operation. In this case, there’s no load on source or production servers, networks, and disks, since no data is copied from the source machine. You can use a synthetic backup when system requirements or time do not allow for a complete backup. Advantages of synthetic backups include shorter data backup and recovery times. It also means you get to reduce your backup cost since you will only use a little storage space.

Also, synthetic backups only partially tax the network during the backup itself because they only transfer or copy changes.

There is only one disadvantage of synthetic full backups, which is that it tends to overwrite existing backups during the process of combining them. You might save time and storage space. However, you might not be able to get multiple versions of a specific file. Ultimately, synthetic full backups allow you to make full backups more often without monopolizing precious storage space or bandwidth. Moreover,  having a complete data backup is always the best way to protect your business from a data catastrophe.

Which Backup Strategy is the Best?

There is no set backup strategy you have to follow. You can choose to use one or more backup methods based on your business needs, network bandwidth, or storage space consumption. Most businesses follow this pattern; An initial full backup, then a differential or incremental backup, followed by another full or synthetic full backup occasionally. You only need to decide which backup strategy would work for your organization based on the following;

  • The amount of data you are copying
  • The time you can devote to the backup process
  • The software program and operating system your company uses
  • How quickly you will need to recover lost data in case of an emergency, accident, or natural disaster

Other Forms of Data Backup

Aside from the major backup strategies discussed in the article, there are other minor forms of data backup. They include;

  • Reverse Incremental Backup:

This starts with a full backup and then a reversible injected incremental backup.

In a forever incremental backup, only one initial backup is required, and subsequent backup schedules track and store only the modified data since the previous backup indefinitely.

It stores the exact copy of your data separately. It differs from a full backup by applying no deduplication and compression to your data.

This advanced backup strategy auto-saves your changed data in real time. In this process, a backup of the change is made whenever the software or operating system detects a change.

Conclusion

There are many stories of businesses getting in trouble due to the data they lost. Some of them couldn’t even function due to the data loss. Unfortunately, they could have prevented all the loss of data, time, and money by using an effective data backup system.

As discussed in this article, there are four major types of data backups, but the main difference between them is the full backup. All the other backup strategies must start with a full backup. You can decide to use the full backup alone or pair it with either a differential or incremental backup.

Furthermore, your backup strategy should reflect your business needs and recovery objectives. The most crucial thing to remember is that it doesn’t matter which backup strategy you choose and how much it suits your needs. Any backup is better than having no backup and losing your data if or when any problem arises.

text written by:

Paweł Piskorz, Presales Engineer at Storware