Synthetic full backup: This method combines a full backup with the changes made since the last backup to create a new full backup. It can be faster than a full backup and uses less storage space.
Incremental backup: This method backs up only the data that has changed since the last backup, making it faster and using less storage space than a full backup. However, it may require multiple backups to restore all data.
Differential backup: This method backs up all changes since the last full backup, making it faster than an incremental backup. However, it uses more storage space and may require both the full and differential backups to restore data.
Archive backup: This method is used to create a permanent copy of data that is no longer in use but must be retained for compliance or legal reasons.
Open file backup: This method is used to back up files that are in use and may be locked by the operating system or an application.
Snapshot backup: This method creates a point-in-time copy of data, allowing for quick and easy restoration. It is commonly used in virtual environments.
These backup methods can be combined and customized to meet the specific needs of a server environment.
In server administration, backup and restore are crucial processes for ensuring data protection and continuity in case of unexpected events, such as system failures, natural disasters, or cyber attacks. Here are some key concepts related to backup and restore:
Backup frequency
This refers to how often backups are performed. The frequency may vary depending on the criticality of the data and the rate of change. For example, a database that is constantly updated may require more frequent backups than a static file.
Media Rotation
This is the practice of using multiple backup media (such as tapes or disks) in a rotating schedule to ensure that data is stored on different devices and locations. This reduces the risk of data loss in case one of the media fails or becomes inaccessible. The rotation schedule may involve daily, weekly, monthly, or yearly intervals, depending on the organization's policies.
Backup media types
There are different types of backup media that can be used depending on the needs and budget of the organization. Some of the most common types are:
Tape: This is a traditional backup medium that offers high capacity and durability but requires specialized hardware and software to use.
Cloud: This refers to storing backups on remote servers or data centers provided by a third-party vendor. Cloud backup offers scalability, accessibility, and off-site storage, but it may be subject to network latency, security risks, and subscription fees.
Disk: This includes hard drives, solid-state drives, or network-attached storage (NAS) devices that offer fast backup and restore speeds, high capacity, and affordability. Disk backup can be used as primary or secondary backup media, depending on the organization's needs.
Print: This involves printing out important documents and files as a backup measure. This method is mostly used for archival purposes or for critical documents that cannot be lost, but it is not very practical for large amounts of data.
File-level vs. system-state backup
Backup can be done at different levels of granularity, depending on whether the organization needs to back up individual files or the entire system state. File-level backup is a selective method that allows organizations to choose which files or directories to back up, while system-state backup captures the entire operating system, applications, and data, including registry settings, system files, and configuration information. System-state backup is usually required for disaster recovery purposes or for migrating to a new system.
Overall, backup and restore are critical processes that require careful planning, testing, and monitoring to ensure that the data is protected and available when needed.
