Prüfungsvorbereitung Backup Beispiel

IT-Ausbildung Videotraining

25 Apr 201605:52

Summary

TLDRThe video script discusses backup strategies for a fictional hair salon, illustrating the concepts of full, incremental, and differential backups through a weekly schedule. On Sunday, a full backup is performed, capturing all files. From Monday to Friday, incremental backups are conducted, which only save files that have changed since the last backup. This approach ensures smaller backup sizes and efficient storage use. On Saturday, a disk failure is simulated, and the importance of having a fallback strategy is highlighted. The video also explains the differential backup strategy, where the backup includes all changes since the last full backup, without resetting the archive bit, thus saving storage space. The script emphasizes the need for a comprehensive backup strategy to protect against data loss, and invites viewers to engage with questions or comments.

Takeaways

📅 Incremental backups are performed from Monday to Friday, capturing changes since the last full backup on Sunday.
🔥 A full backup, or 'firework', is conducted on Sunday, ensuring all files are archived and can be restored.
📈 Incremental backups on days with file changes only save the changes since the last backup, reducing storage space needed.
🗄️ The backup program does not recognize changes from previous days if the archive bit is reset, focusing only on new changes.
📝 Differential backups, conducted from Monday to Friday, include all changes since the last full backup, without resetting the archive bit.
🔄 The archive bit, when set, indicates to the backup program that files have changed and need to be included in the backup.
🚫 If the archive bit is not reset, the backup program includes all changes from the last full backup to the current day in the differential backup.
💾 The last differential backup is sufficient for restoration because it includes all changes up to that point.
🗑️ Backups can be selectively deleted to save space, as long as the last full and differential backups are retained.
🔧 In case of a disk failure, the most recent backup can be used as a fallback to restore the system to its state at the time of the backup.
♻️ Daily backups, or 'daily government', are conducted without resetting the archive bit, requiring a full backup plus all daily backups for restoration.

Q & A

What are the three types of backup strategies mentioned in the video?
-The three types of backup strategies mentioned are full backup, incremental backup, and differential backup.
What does a full backup include?
-A full backup includes all files, regardless of whether they have been changed since the last backup.
How does an incremental backup work?
-An incremental backup only backs up files that have changed since the last backup, whether it's full or another incremental.
What is the purpose of a differential backup?
-A differential backup backs up all files that have changed since the last full backup, regardless of subsequent incremental or differential backups.
Why is the archive bit used in backups?
-The archive bit is used to mark files that have been backed up, which helps backup software determine which files need to be backed up in subsequent backup operations.
What happens when the archive bit is reset in the context of backups?
-When the archive bit is reset, it indicates to the backup software that the file has not been backed up since the last backup operation, causing it to backup the file again.
How does the video's example of a hair salon's backup strategy illustrate the use of incremental backups?
-The hair salon's backup strategy uses incremental backups from Monday to Friday, which means only files that have changed on each day are backed up, reducing the size of the backup and saving time.
What is the advantage of using differential backups over incremental backups?
-Differential backups are easier to manage and restore because they only require the last full backup and the latest differential backup to restore the system to the latest state.
What does the video suggest to do with backups after a successful full backup?
-The video suggests that after a successful full backup, you can optionally discard or overwrite previous backups to save storage space.
What is the fallback strategy mentioned in the video?
-The fallback strategy mentioned involves using a copy of the full backup to restore the system to a known good state in case of a hard drive failure or other data loss events.
What does 'daily backups' mean in the context of the video?
-Daily backups refer to the practice of conducting backups every day without resetting the archive bit, which means that all files are backed up each day, regardless of whether they have changed or not.
Why might one choose to perform daily backups instead of incremental or differential?
-One might choose daily backups for simplicity or in scenarios where the data is critical and it's necessary to have a backup for every single day, even if it means using more storage space.

Outlines

00:00

📚 Incremental Backup Strategies in a Hair Salon

This paragraph introduces the concept of incremental backup strategies using the example of a hair salon named 'IKS'. The salon has a backup strategy that involves full, incremental, and differential backups. The explanation covers how these backups work over a week, starting with a full backup on Sunday, followed by incremental backups from Monday to Friday, and a full backup again on Saturday in case of a hard drive failure. The key point is that only the files that have changed since the last backup are saved, which makes the backup process more efficient and saves storage space.

05:01

🔄 Differential Backups and the Role of Archiving

The second paragraph delves into the topic of differential backups and the importance of archiving in the backup process. It explains that differential backups involve backing up only the files that have changed since the last full backup. The paragraph also discusses the use of archiving to mark files that have been backed up, which helps in managing the backup process and ensuring that only the necessary files are included in each backup. The summary emphasizes the efficiency of differential backups and the significance of archiving in maintaining a robust backup strategy.

Mindmap

Keywords

💡Backup Strategies

Backup strategies refer to the methods and schedules used to ensure data is safely stored and can be restored in the event of a failure or loss. In the video, the speaker discusses different types of backup strategies, such as full, incremental, and differential backups, which are crucial for data recovery and are the central theme of the video.

💡Incremental Backup

An incremental backup is a method where only the data that has changed since the last backup is saved. This is contrasted with a full backup, which copies all data. In the video, the incremental backup strategy is exemplified by the changes made to the files from Monday to Friday in the hair salon scenario, highlighting its efficiency in saving storage space and time.

💡Differential Backup

A differential backup involves backing up all the data that has changed since the last full backup. Unlike incremental, it does not require multiple incremental backups to restore data. The video uses the hair salon example to illustrate how differential backups include changes from both Monday and Wednesday without resetting the archive bit, thus requiring only the last differential backup for restoration.

💡Archive Bit

The archive bit is a file attribute that indicates whether a file has been changed since the last backup. In the context of the video, the speaker explains how the archive bit is used in incremental and differential backups to determine which files need to be backed up. It plays a critical role in the backup process described for the hair salon scenario.

💡Full Backup

A full backup is a complete backup of all selected data. It is the most comprehensive form of backup and is often used as a base for other types of backups. The video mentions that a full backup is necessary to restore the system to a known state, especially when combined with incremental or differential backups.

💡Data Recovery

Data recovery is the process of retrieving lost data due to accidental deletion, corruption, or hardware failure. The video's theme revolves around strategies for data recovery, emphasizing the importance of regular backups to ensure that data can be restored in case of any data loss incidents.

💡File System

A file system is the method and data structure that an operating system uses to control how data is stored and retrieved. The video script mentions the file system in the context of the hair salon's data management, which is crucial for understanding how backups interact with the system's files.

💡Storage Space

Storage space refers to the physical or virtual space available on storage devices for saving and organizing files. The video discusses the efficiency of different backup strategies in terms of storage space, particularly how incremental and differential backups save space by only storing changes rather than entire datasets.

💡Data Change

Data change refers to any modification, addition, or deletion made to data in a file or database. The video uses the concept of data change to explain when and which files need to be included in incremental and differential backups, which is fundamental to understanding the process of backing up data.

💡Restoration

Restoration is the process of returning data or a system to its original state after a failure or loss. The video emphasizes the importance of having a good backup strategy for efficient restoration, particularly in the context of the hair salon's data management.

💡Hardware Failure

Hardware failure refers to the malfunction or breakdown of a physical component in a computer system. The video script alludes to the risk of data loss due to hardware failure as one of the reasons for implementing backup strategies, highlighting the need for data protection against such events.

Highlights

Introduction to the video on exam preparation for IT specialists focusing on backup strategies.

Explanation of full, incremental, and differential backup strategies.

Example of a hair salon's backup strategy, including full backups on Sundays and incremental backups from Monday to Friday.

The importance of understanding which backups are necessary in case of a hard drive failure on a Saturday.

Detailing how incremental backups capture only the changes since the last full backup.

Demonstration of how to restore files using a full backup and incremental backups.

The concept of 'archive bit' and its role in backup strategies.

Differentiating between incremental and differential backups and when to use each.

The process of performing differential backups from Monday to Friday, including what gets backed up.

Explanation of how the archive bit is not reset in differential backups, allowing for tracking of changed files.

The impact of the archive bit on the size of backups and the importance of only backing up changed files.

Advantages of differential backups in terms of storage space and efficiency.

Discussion on the use of copy backups for creating an identical effect without resetting the archive bit.

Strategy for handling backups in the event of a hard drive failure, including the use of differential and full backups.

The option to delete previous backups to save space, given that a recent full backup exists.

Explanation of daily backups, their execution, and the concept of not resetting the archive bit.

The necessity of having a full backup plus all daily backups for restoration purposes.

Conclusion on the importance of understanding backup strategies for IT specialists.