Ⅰ. Backup method, maintenance, product selection
1. Backup method
Common backup methods are:
(1) regular tape backup data.
(2) Remote key data + tape backup. Tape is used to back up data, and the production machine sends key data to the backup machine in real time.
(3) Process tape library, CD library backup. That is to transfer the data to the remote backup center to make a complete backup tape or CD.
(4) Network data mirroring. This method is to monitor and track the update of the database data of the production system and the important target files that need to be tracked, and transmit the update log to the backup system through the network in real time, and the backup system updates the disk according to the log.types of backups
(5) remote database backup. It is to create a copy of the main database on the backup machine that is separated from the production machine where the main database is located.
(6) Remote mirror disk. The mirror disk is extended to a place far away from the production machine through high-speed fiber channel lines and disk control technology. The mirror disk data is completely consistent with the master disk data, and the update method is synchronous or asynchronous.
Data backup must take into account data recovery issues, including multiple disaster prevention measures such as dual-system hot backup, disk mirroring or fault tolerance, off-site storage of backup tapes, and redundancy of key components. These measures enable system recovery after a system failure. However, these measures generally can only deal with computer single-point failures, and are helpless to regional and destructive disasters, and do not have disaster recovery capabilities.
2. Maintenance
The purpose of the automatic backup system is to reduce the maintenance workload. As long as the system is implemented, the maintenance work can be relaxed. It is only necessary to check the backup status after a week or a month.
After the user implements the backup system, the maintenance of the backup system is still very important. Mainly determined by the following factors:
(1) Since many IT systems in many units have many hosts and many application systems, and each application system has corresponding management and maintenance personnel, backup is the centralized management of various application data backup tasks. Therefore, for users with complex application systems, backup system administrators or storage backup engineers can be set up to maintain the overall backup system.
(2) The technology involved in the backup system includes operating system, database, storage, tape library and many other technologies. Therefore, it is recommended that the backup system administrator have a certain understanding of various knowledge, and in addition to participating in the training of backup system knowledge, he must also participate in Professional training for operating systems, databases and other products to ensure that the application system can recover data as soon as possible in the event of a disaster.
(3) As the amount of data increases and the application system grows, the backup strategy should be optimized over time.
(4) If there is a "cloning" function in the tape library backup system, it is also necessary to take out the "cloned" media every day and store them in a different place for disaster recovery.
(5) If the daily backup of the key database fails, it may lead to the suspension of the database. For example, for an Oracle database, if the "archive log" of the database is not backed up in time, it will cause the entire database to stop.
3. Select the product
(1) When selecting products, the capacity of the backup tape library should be as large as possible, the speed of the tape drive should be as fast as possible, and the most advanced technology should be used as much as possible.
(2) In the process of product selection, cost performance is one of the most important indicators, but it is by no means all. It is recommended that users consider the following factors when choosing a product:
The system application data type, data volume, backup strategy (full backup, incremental backup, etc.) and key data retention time determine the total capacity of the tape library;
The peak data volume of the backup time window and the backup data volume determine the minimum number of tape drives;
The types of application systems and data types determine which technologies are used for backup.
(3) In terms of tape drive technology selection, it is recommended to choose a more general device. For this tape drive, the operating system and backup software are more compatible with it.
(4) If NAS equipment is used for backup, try to choose NDMP backup; for SAN architecture backup, try to use tape drives for dynamic sharing; disk arrays provide mirroring or SNAP functions, and SnapShot backup technology can be used.
(5) Since the tape drive is a mechanical device, the failure rate is higher than that of disks, CDs and other equipment, so try to keep redundancy when configuring the tape drive. SATA disk technology has developed by leaps and bounds, and disk backup technology has become the development direction.
(6) Hardware equipment considers the provision of spare parts and the service level of the provider, and for backup software, the provision of professional services and technical support is also an important factor to be considered.
Ⅱ. What is the difference between backup and archive?
1. backup
Backup is a data protection strategy in which a copy of data is created so that it can be recovered if the original data is lost, corrupted or compromised. Backups typically focus on data availability and business continuity. Backups are copies of data created in response to data loss, corruption, or catastrophic events so that they can be restored if required.
The main goal of backup is to ensure rapid recovery in case of data loss or corruption. They provide a means of recovering data to keep the business running. Backups can be performed on a regular basis such as daily, weekly or monthly as required. It depends on business needs and how quickly the data changes.
The backup retention period can be set according to business policy. Old backups may be overwritten by new ones to save storage space. Usually stored on relatively easy-to-access storage media, such as hard drives, cloud storage, etc. Backup data can usually be restored quickly to ensure minimal business disruption.
Backups are usually performed on a regular basis, which can be daily, weekly, or monthly, etc., to ensure data freshness and accuracy. Old backups are usually overwritten by new ones to keep backup storage sized reasonably. The design goal of backup is to quickly restore data in the event of a disaster, so backup data is usually stored on relatively easy-to-access storage media.
2. Archive
Archiving is a data management strategy designed to move infrequently used but still valuable data to less expensive storage media to free up primary storage space and meet compliance and regulatory requirements.
The main goal of archiving is to preserve data long-term to meet compliance requirements, regulatory demands, and legal requirements. They are not just for data recovery, but for long-term retention and regulatory storage needs. Archiving is usually performed when the data no longer needs to be accessed frequently, for example, some historical data, data from old projects, etc.
Archived data needs to be retained for long periods of time, possibly years or even decades. Data immutability and integrity are key. Archived data is usually stored on less expensive media, such as tape storage, because archived data does not require frequent access. Archived data can be slower to restore because they are stored on relatively slow media.
Ⅲ. The connection and difference between backup and data synchronization
1. contact
Business Continuity: Both backup and data synchronization are closely related to business continuity. Backups ensure rapid recovery in the event of data loss, while data synchronization helps ensure data across multiple locations stays in sync for consistency in collaboration and business operations.
Data replication and protection: Both backup and data synchronization involve copying data from one location to another to protect data from the risk of corruption, loss, or deletion. They all help ensure the availability and integrity of data.
Data Recovery: Both backup and data synchronization can be used to restore data when needed. Backups are used to recover data from catastrophic events, while data synchronization can be used to maintain data consistency across multiple devices.
2. Difference
(1) Main purpose:
Backup: The primary goal of backup is for data recovery in the event of data corruption, loss, or catastrophic events. Backups are usually periodic and are designed to create historical copies of data in order to restore a system to a previous state.
Data Synchronization: The main goal of data synchronization is to ensure that data in multiple locations stays in sync. Data synchronization is usually real-time or on-demand and aims to maintain data consistency across multiple devices.
(2) Storage and retention:
Backup: Backup data is usually stored on backup devices, external hard drives, cloud storage, etc. for future recovery. Old backups may be replaced by new ones.
Data Synchronization: Data synchronization typically involves copying data between multiple devices to ensure their data remains consistent. Synchronized data typically does not hold multiple historical versions like backups do.
(3) Frequency and method:
Backups: Backups are usually performed on a schedule, such as daily, weekly, or monthly. Backups may retain multiple versions of data for restoration at different points in time.
Data Synchronization: Data synchronization can be real-time, ensuring that data on multiple devices is always up-to-date to stay in sync during collaboration.
(4) Data consistency:
Backup: The point of backup is the historical state of the data so that it can be rolled back to the previous state if required.
Data synchronization: Synchronization emphasizes maintaining data consistency on multiple devices, ensuring that data in multiple locations is always the same.
(5) Recovery and access speed:
Backup: Backup data can often be used to quickly restore systems and data to minimize business disruption.
Data synchronization: Data synchronization emphasizes the real-time and consistency of data, rather than rapid recovery when disasters occur.
Ⅳ. What are the advantages and disadvantages of data backup?
1. Advantages:
Data Recovery and Business Continuity: The main purpose of backup is to restore data in the event of data loss, corruption, accidental deletion or catastrophic events. Backup can help you quickly restore data, maintain business continuity, reduce downtime, and avoid the impact of data loss.
Version control and history: Backups often create multiple versions of data, enabling you to restore data at different points in time. This is useful for tracking data changes, rolling back to previous states, and finding specific data.
Prevent Data Loss: Backups protect data from various risks such as hardware failure, viruses, ransomware, human error, and more. Even in the event of data corruption or deletion, data can still be restored from backup to avoid permanent data loss.
Disaster Recovery: Backups are a core component of any disaster recovery plan. In the event of natural disasters, fires, floods, etc., backups can help organizations recover affected systems and data quickly.
Data Security: Backups can increase data security. Even if attacked by ransomware, backups can be used to restore affected data without paying the ransom.
Compliance and regulatory requirements: Backups can help organizations meet compliance and regulatory requirements, such as data retention periods and more.
Test and Development: Backups can be used for test and development environments, ensuring that these environments are consistent with production environments, reducing errors and inconsistencies.
Data migration and replication: Backups can be used to migrate data between different hardware devices, operating systems or cloud platforms, so as to achieve smooth data migration and replication.
Data Recovery Testing: Regularly testing your backup recovery process can help you verify that your backups are valid, ensuring that your data can be restored when actually needed.
2. Disadvantages:
Cost: Implementing and maintaining a backup solution may require certain investments, including hardware equipment, storage media, backup software, and human resources. Especially when multiple historical backup versions need to be kept, storage costs can increase.
Security risks: Backup data may contain sensitive information, which can lead to data breaches and security risks if the backup data is not properly encrypted and protected.
Resource requirements: The backup process may consume computer resources and network bandwidth, especially when backing up large amounts of data. This may affect normal system performance, resulting in slower system response during backup operations.
Data Consistency: Backup operations can interfere with running applications or databases, potentially causing data consistency issues. To avoid this, backups are usually performed during off-peak hours.
Management Complexity: As the volume of data increases, the management of backup operations becomes more complex. Ensuring proper execution of backup policies, monitoring backup health, and handling backup errors can require specialized management and skills.
Data Expiration and Cleanup: Backup data may become obsolete or no longer needed, but due to poor management, this data may continue to take up storage space and increase storage costs. Backups that are no longer needed need to be cleaned up regularly.
The necessity of recovery testing: The validity of backup data needs to be regularly tested and verified. Without regular recovery testing, there is no way to ensure that data can be successfully recovered when it is actually needed.
Single point of failure: If backup storage and source data are in the same physical location, backup data can also be affected in the event of a hardware failure, disaster, or disruptive event.
Backup cycle and frequency: The cycle and frequency of backups must be carefully planned, otherwise the window of time for data loss may increase. Too frequent backups can waste resources, while too few can increase the risk of data loss.
Ⅴ. Describe backup from different angles
1. Disaster recovery perspective: From a disaster recovery perspective, backup is a core component of a disaster recovery plan. Backup data can help organizations quickly restore critical systems and data in an emergency, mitigate the impact of a disaster, and enable businesses to restart quickly.
2. Data protection perspective: From a data protection perspective, backup is a defensive measure designed to protect data from various potential threats. Through backup, data can be restored in the event of accidental data deletion, hardware failure, ransomware attack, malware infection, etc., ensuring data security and availability.
3. History and version control perspective: Backup provides data history and version control functions. Viewed in this way, a backup is a time machine that allows you to see the state of your data at different points in time and roll back to a previous version if needed.
4. From the perspective of business continuity: From the perspective of business continuity, backup is regarded as a key strategy to maintain the smooth operation of the business. It ensures that in the event of a catastrophic event, natural disaster, hardware failure, etc., the business can quickly resume normal operation, reduce downtime, and maintain customer satisfaction.
5. Data compliance perspective: For compliance and regulatory requirements, backup is a necessary practice. It helps organizations follow data retention and backup policies to meet regulatory requirements and ensure data auditability.
6. Innovation and testing perspective: Backup can also play a role in innovation and testing. Backup data can be used to test new features, application updates, and system changes to ensure that these changes do not affect the stability of the production environment.
7. From the perspective of risk management: From the perspective of risk management, backup is an important means to reduce business risks. It can help organizations reduce the risk of data loss, reduce the loss caused by business interruption, and maintain the organization's reputation.
8. Technical recovery perspective: From the perspective of technical recovery, backup is a means of restoring damaged technical infrastructure. Whether it's a hardware failure, operating system crash, or network problem, backups can help system administrators restore their systems to a stable state.
