What is incremental backup? Backup: the most effective methods for different tasks. Differential Incremental Backups

What is an incremental backup?

Incremental backup.
Copy only new and changed files.

Incremental backup (incremental backup)- this is a type of differential backup, when not all source files are copied, but only new and modified since the creation of the previous copy - full or incremental. This significantly saves disk space and significantly speeds up the backup process.

The name of this type of backup comes from the English word Incremental backup- additional. In Russian it is called Additional. This type Reserve copy is the most common, but like all methods, it also has its pros and cons.

This type of backup is perfect for backing up large volumes of source data, 50 gigabytes or more. The speed of creating backups will be quite high, and the size of each additional copy can be only 100-200 megabytes.

Pros :

• Quick backup
• Small volume occupied by the backup copy (saving disk space)

Minuses :

• Complexity of setup (compared to a full copy of Full Backup)
• Difficulty of recovering files (compared to a full copy)

Conclusion: Create incremental backups if the volume of source data is large and the time it takes to copy files and save disk space is important to you. The optimal frequency for creating an Incremental backup is 1 time per hour if the source files are changed frequently and 1-2 times a day if the files are edited rarely.

How to make an incremental backup using Exiland Backup

Exiland Backup- a simple utility for backing up and synchronizing folders over the network, FTP, between PCs and servers. Supports all types of file backups.

This universal program well suited for backing up file 1C, sites on Wordpress and other CMS, copying site files from an FTP server to a local PC.

After launching, in the main window of the program, on the top panel, click the button to create a new task, specify the name of the task, for example, “My Documents” and click “Next”. Now, as shown in the screenshot below, select the copy type “Incremental”.

Screenshot of the program. Selecting the copy type.

Below there is an option to limit the number of full copies so that the oldest backups are automatically deleted before creating a new full copy. This setting saves disk space (not available in Free versions). You can also limit the number of incremental copies between full ones. When this limit is reached, another full copy will be created.

When choosing a backup naming template, you can add a line such as "(incremental)" for incremental backups to visually distinguish them from full ones.

When the task is created, you do not have to wait for the start time - you can start the task manually by clicking on the "Run" button located on the top panel.

Mikhail, program developer

Other types of copying.

Many people know various systems creating disk images and backing up data, such as Acronis True Image, Pagaron Drive Backup, Ghost, Time Machine for Mac-compatible computers, etc. Microsoft has also implemented a data backup system in its operating systems, which is available for both ordinary users and system administrators. Before the release of the operating system Windows Vista Microsoft offered users the NTBackup backup system and the System Restore utility, which had a lot of shortcomings. With the release of Windows Vista and the transition to the VHD image storage format, it became possible to more easily back up data and create operating system images using a new set of utilities called Windows Backup and Restore. After the release of new operating systems, this component was improved and modified. In this article, we will look at what Microsoft offers to the end user for backing up data in the recently released Windows 8 operating system. But first, we will briefly talk about the main types of backup that are implemented in numerous products from various companies.

Types of backup

Backup is divided into different kinds depending on the tasks that are set for those implementing it software. In some cases, users only need to create copies of important files stored on the disk; in others, they need to create full-fledged images of the operating system with the ability to roll back all previous changes. At the same time, system administrators are provided with the ability to centrally store backup copies of data, making it easier to control backup versions and restore systems as needed. Naturally, depending on the selected type of backup, one or another algorithm for comparing and saving files is used - either byte-by-byte or sector-by-sector copying from the data source, when the information is exactly written to the backup media. To restore files and data, the functions of file systems that support journaling and logging of changes can also be used - first, a complete snapshot of the file system is taken, and data is saved to a backup copy as needed if individual files are marked as changed. File systems with advanced version control support are best suited for this case, since they significantly save space on backup media. In addition to the traditional creation of backup copies of files that are not used in this moment, there are real-time reservation algorithms. In this case, backup occurs even when the file is open in any program. This capability is achieved through the use of snapshots of file systems and is actively used, for example, in virtualization systems for working with virtual disk drives. The data backup process can occur in several ways. Let's look at the most common of them.

Cloning partitions and creating images

Cloning involves copying a partition or partitions of a disk with all files and directories, as well as file systems to backup media, that is, creating a complete copy of the data on another media. This requires a large amount of space on the backup media, but at the same time allows for the most complete backup of an individual PC or data drive. Also, special mention should be made of cloning the system in the form of a special image - a virtual drive, that is, a separate file that can contain several disk partitions. Such an image can be created using the operating system itself. It allows you to reduce the amount of data, and also provides the opportunity to subsequently work with it as with a regular disk, or connect it to virtual machines, which simplifies the transfer of operating systems from one server or computer to another. Today, virtual images are gaining popularity due to the flexibility of connection, as well as cross-platform and easy transfer from one computer to another. As a rule, cloning or creating an image for backup occurs quite rarely, since the volume occupied by the backup is very large. Such procedures are used in most cases specifically to create a copy of the operating system with all the files, and not to back up individual data on disk. To back up user data that changes frequently or is used in work, another type of backup is widely used - full file backup.

Full file backup

This type of backup involves creating duplicates of all files on the media. simple method- copying from one place to another. Due to the length of the process, a full file backup is usually carried out during non-working hours, due to the large volumes of data. This type of reservation allows you to save important information, but due to the long backup periods, it is not very suitable for restoring rapidly changing data. It is recommended to carry out a full file copy at least once a week, and even better, alternate it with other types of file copying: differential and incremental.

Differential redundancy

Differential backup involves copying only those files that have changed since the last full backup. This allows you to reduce the amount of data on backup media and, if necessary, speed up the data recovery process. Because differential backups are typically performed much more frequently than full backups, they are very effective because they allow you to restore data that has recently been modified and track the history of file changes since the full backup.

Incremental backup

Incremental backup is somewhat different from differential backup. This means that the first time you run it, it backs up only those files that have changed since the last time you ran a full or differential backup. Subsequent incremental backup processes only add files that have changed since the previous backup process. In this case, changed or new files do not replace old ones, but are added to the media independently. Of course, in this case, the file change history increases with each backup step, and the data recovery process for this type of backup takes much longer, since it is necessary to restore the entire file change history, step by step. However, with differential backup, the restore process is simpler: the primary copy is restored and the latest data from the differential backup is added to it.

Many backup software packages use different types of backups, and often combine them to be more efficient and save space. System utilities Windows, which we will talk about in this article, also use various types of backups, which allows you to more dynamically and quickly restore user data depending on the situation. For server operating systems Windows systems available large quantity recovery utilities than for desktop Windows operating systems, but here we will consider only those that are available to ordinary users. Moreover, for different editions of Windows OS the set of components differs, which is due to the division of operating systems into corporate and home. For Windows operating systems, there are two main data backup utilities, which differ in the type of backup.

Windows Backup And Restore

Windows component Backup And Restore has become available to users since the release of the Windows Vista operating system and is responsible for creating a complete backup of the operating system with the possibility of incremental backup. With the release of the Windows 8 operating system, this component changed its name to Windows 7 File Recovery. Although it has not lost any of its functionality, Microsoft recommends using the new File History utility for backing up data, which is included in the Windows 8 and Server 2012 operating systems, but we will talk about it a little later. Windows Backup And Restore allows you to create an automatic full backup to removable media, optical disks, or to a special location on a remote server.

The latter feature is available only for certain editions of Windows 7/8, as it is positioned as a solution for IT administrators of companies. A full system backup when using this component involves not only saving user files, but also the ability to create an image of the entire operating system and backup individual computer disks. It is also possible for the user to create an exclusively system image, which can subsequently not only be extracted to a new media of this computer, but also used as virtual disk in virtualization systems. When using this component, the user can specify the folders that need to be backed up, as well as indicate those system drives that need to be saved during a full backup. When backing up files only Windows user Backup And Restore uses incremental data backup, which allows you to get a larger number of snapshots of files at different points in time. Typically, a full backup is performed once a week and involves not only backing up user files, but also creating a system image, as well as copying data for component restore points Windows System Recovery. The process of restoring user files can occur directly from the operating system - it is quite simple and understandable for most users. System recovery in the event of a serious failure can be carried out using the built-in Windows Recovery utilities. To do this, you must either create a new dedicated recovery disk or use installation image operating system from which it was previously installed on the PC. When loading in mode Windows recovery Recovery will offer the user a choice of the following recovery modes: restoring files, moving to a specific recovery point, extracting a backup system image to the main system drive. Data for recovery in this case can be taken from optical media, external or internal storage, as well as from network data storage. The operating system edition does not play a role in this case. Alas, despite the fact that Windows Backup And Restore is a fairly powerful and convenient component of the operating system, Microsoft stated that, according to research, this utility is used by, at best, 5% of users. In this regard, to make data backup simpler and more efficient, Microsoft has developed the next generation of system backup for users - Windows File History.

Windows File History

Windows File History, a new component of the Windows 8 and Server 2012 operating systems, in some ways replaces its predecessor, Windows Backup And Restore. It is intended to replace only incremental file backup, while system imaging and full backup mode can be performed exclusively with using Windows 7 File Recovery. Windows File History was originally designed as a convenient and practical solution for users who want a transparent way to back up their important data. When developing this utility Special attention attention was paid to the simplicity of initializing the process, combined with the ability to conveniently and quickly view all saved data. The backup process using the new utility occurs unnoticed by the user in automatic mode and does not require additional actions from him. It should be noted that the modification of backup to network devices allows you to easily and conveniently work with saved files if you use mobile connections or weak communication channels.

As a basis Windows utilities File History was taken as part of the basic functionality of Windows Backup And Restore, in which the visual component responsible for presenting saved user data was redone. Viewing previously saved data is now available from file manager Windows Explorer using a separate History tab. This allows you to quickly find the necessary files and restore them to any location on the system. Despite the fact that the backup process is based on an incremental backup, when working with it there is no thought that this is a backup, but rather a history of the creation, modification or deletion of user files, available at any time. This approach to data backup will certainly suit most inexperienced users, since the process is convenient and more intuitive to use than working with Windows Backup And Restore.

To back up data using Windows File History, you can use optical media, external drives, or network storage. Of course, storing data on optical media is more of a tribute to tradition than a real method of using incremental backup, because data can change very often. Optimal choice For ordinary users, backup to an external or internal drive is necessary.

For ease of use in Windows 8, each connected external storage can be used as a backup tool using Windows File History. So, if the drive is connected, the options in the autorun drop-down menu now have a separate tab that allows you to designate the connected drive as a backup drive in one click. Moreover, even if the disk was subsequently disconnected from the system, data backup will resume as soon as it is installed back. A similar approach is applied in the case of backing up data to network storage. Disconnect from local network will not affect the operation of the system in any way, and when a network environment appears operating system will automatically start a new reservation cycle according to the schedule. The transparent system for activating Windows File History functions is truly a huge plus for the user.

By default, backups using the Windows File History utility occur every hour, but if necessary, the user can choose the time intervals between each data backup. The user has the opportunity to set intervals between reservations from 10 minutes to 1 day. Windows File History can only set one current backup location, but if you add multiple drives to backup locations, they can be used interchangeably depending on their availability. This is convenient when using network storage and a separate drive. This way, the data will be saved to multiple places depending on the current configuration. Also worth noting is the function of selecting the number of depths of saved copies. For example, after one or several months, the system can automatically overwrite old data, replacing it with new ones. This allows you to save space in the place where data is backed up. In addition, the user can use up to 25% of the storage space for data backup.

The Windows File History utility by default backs up the most actively used folders, namely Contacts, Favorites, and Desktop. In addition, the reservation is automatically applied to all Libraries folders in use. The user can create their own data libraries, which are essentially symbolic links to real folders on the computer. That is, if a user needs to reserve a specific folder on a PC, he has to Windows installation File History you need to add this folder to your libraries. In addition, if some folders need to be excluded from the backup, the user can selectively exclude all user libraries or a set of frequently used folders. Taking into account active integration with the cloud storage function Windows data Skydrive's use of this cloud service can be aimed at backing up important user data stored in the cloud. In order for such a combination to work, you only need to install Skydrive - after that it will automatically be added to the libraries and will be backed up as needed. Alas, the function of backing up data to the “cloud” is not yet available to users, but Microsoft is already planning to add a certain ability to back up data to “cloud” data storage in future versions of its OS.

Thus, new system Windows File History backup is great for most users. A simple and intuitive interface with the ability to quickly add and restore files is much closer to the modern user than previous version incremental backup in Windows Backup And Restore.

Incremental backup allows you to effectively save information that is constantly changing: documents, projects in development, mail backup, etc. Handy Backup - incremental backup program any files.

What is incremental backup?

Incremental copy is a copying method in which additions are added step by step to the original copy of a data set, reflecting changes in the data (these step-by-step changes in the data set are called increments).

For example, if out of 200 files in the original set only 3 are changed, then they will be copied during the next incremental backup.

The incremental backup program must provide the ability to regularly make such additions, as well as their step-by-step recovery if necessary.

In this mode, incremental copying is repeated cyclically, starting with a full data backup. When the number of incremental backups reaches the specified value or statute of limitations, the entire cycle is repeated automatically, starting with the creation of a new full copy.

The key advantage of a mixed incremental backup is its ability to break off too long chains of increments. This can slightly slow down the backup process, but makes data recovery more reliable and faster.

How to perform incremental backup of files in Handy Backup?

It is very easy to program an incremental backup task in Handy Backup. Select in Step 4 in advanced mode* to create a task incremental or mixed incremental copying.

For mixed incremental copying also set the length or repetition time of the chain of incremental backups in the version settings dialog.

* At Step 1 of creating a task, you must check the box next to "Advanced mode".

Recommended solution for incremental backups

Cross-platform solution for incremental backup

Incremental copying of files and folders in Linux and over the network

In addition to the Windows version, Handy Backup also fully supports executable program Linux distributions, based on Ubuntu 16.04 and 14.04. The program also provides a Java workstation for network Windows, Linux and FreeBSD machines.

Try Handy Backup's capabilities for incremental file backup yourself,
by downloading and installing a free 30-day trial trial version programs with all the functions!

Introduction

Copyright © Acronis, Inc., 2000-2005

What is the difference between full, incremental and
differential backup?

Acronis True Image can

fulfill

incremental

differential backup.

At complete backup, all archived items are included in the archive
data as of the time the archive was created. The complete archive is always available
as the basis for subsequent incremental or differential copying,
you can also use it as a stand-alone archive. Time
recovery of a full archive is minimal compared to time
recovery of incremental and differential archives.

Incremental the archive contains only data that has changed since
creating the last full or incremental archive. Therefore, such an archive
usually has much smaller size and is created somewhat faster. But,
since it does not contain all the data being archived, to restore it
you must have all previous incremental archives and the one created at the beginning
full archive.

Unlike an incremental backup, which adds another
file to the existing “chain”, with differential copying
an independent file is created containing all data changes for
relative to the base full archive. Typically differential
the archive is restored faster than the incremental one, since it does not
there is sequential processing of a long chain of previous
archives.

Full copying as a stand-alone method may be optimal
solution when you need to frequently return the system to the initial state
(for example, in computer club or Internet cafe to eliminate
changes made by guests). In this case, you don't need to recreate it often
original complete image, so the time to create the image is not critical, but the time
recovery will be minimal.

If, on the other hand, you are only interested in the latest state of the data for their
recovery in case of fatal system failure, it is reasonable to apply
differential copying. This method is especially effective when
changes occurring in your data are small in relation to the total
the volume of this data.

This is also true for incremental copying. Maximum benefit
incremental copying is useful when you need to save state frequently
data and be able to return to any of these states. Creating
full archive once a month and incremental archive every day, you will receive
the same result as if a full copy was performed every day. But
time and disk space (or removable media) will be spent
about ten times less.

Please note that the above considerations are nothing more than examples for your
intelligence. We recommend developing your own backup policy

Full, incremental and differential backups

Acronis Backup & Recovery 11 provides the ability to use popular backup schemes such as grandfather-father-son and Tower of Hanoi, as well as create your own backup schemes. All backup schemes are based on full, incremental and differential backup methods. The term "scheme" actually refers to the algorithm for applying these methods in combination with the archive cleaning algorithm.

Comparing backup methods with each other does not make sense, since in the scheme they work together. Each method should perform its own role according to its own advantages. A good backup scheme allows you to take advantage of the advantages of all methods, reducing the impact of their disadvantages. For example, weekly differential backups make archive cleanup easier because they can be easily deleted along with the set of daily incremental backups that depend on them that are maintained throughout the week.

Backup using the full, incremental, or differential backup methods creates the appropriate type of backup.

Full backup

A full backup stores all data selected for backup. A full backup is the basis of any archive and forms the basis for incremental and differential backups. An archive can contain several full backups or consist only of them. A full backup is self-contained: you do not need access to any other backup to restore data from it.

It is widely known that a full backup is the slowest to create and the fastest to restore. With Acronis technologies, restoring from an incremental backup can be as fast as restoring from a full backup.

A full backup is most useful when:

• you need to restore the system to its original state,
• The original state rarely changes, so there is no need for regular backups.

Examples: an Internet cafe, school, or university lab where the administrator frequently undoes changes made by students or guests, but rarely updates the underlying backup (only after installing software updates). The time it takes to create a backup copy is not critical in this case, and the recovery time will be minimal if you restore the system from a full backup copy. For added reliability, the administrator can have multiple full backups.

Incremental backup

An incremental backup stores data changes relative to to last backup. To restore data from an incremental backup, you must have access to other backups from the same archive.

Incremental backups are most useful when:

• you need to restore one of several saved states,

It is widely known that incremental backups are less reliable than full backups because if one copy in the “chain” is damaged, subsequent copies can no longer be used. However, storing multiple full backups is not ideal if you want to have multiple previous versions of your data, because an archive that is too large is even more questionable.

Example: Database transaction log backup.

Differential backup

A differential backup stores data changes relative to last full backup. To restore data from a differential backup, you must have access to the corresponding full backup. Differential backup is most useful when:

• only the latest state of the data needs to be saved,
• the data changes are relatively small compared to the overall data size.

It is generally believed that “differential backups take longer to create and are faster to restore, while incremental backups are faster to create and slower to restore.” In reality, there is no physical difference between an incremental backup attached to a full backup and a differential backup attached to the same full backup at the same point in time. The difference mentioned above implies that a differential backup is created after (or instead of) creating multiple incremental copies.

An incremental or differential backup created after a disk defragmentation may be significantly larger than normal because the defragmentation process changes the location of files on the disk and the backup reflects those changes. After defragmenting the disk, it is recommended to create a full backup again.

The following table outlines the generally accepted advantages and disadvantages of each type of backup. In reality, these parameters depend on many factors, such as the volume, speed and nature of data changes, their nature, the physical characteristics of the devices, and the set backup and recovery options. The best teacher in choosing the optimal backup scheme is experience.

Parameter	Full backup	Differential backup	Incremental backup
Disk space	Maximum		Minimum
Time of creation	Maximum		Minimum
Recovery time	Minimum		Maximum