How to servers make back-ups to hard drives?

Servers make backups to hard drives using various methods and technologies. Here are a few common approaches:

1. External Hard Drives: Servers can connect external hard drives to the system and use backup software or scripts to copy data onto those drives. The drives are typically connected via USB, eSATA, or Thunderbolt ports. Backup applications can schedule regular backups and perform incremental or full backups based on predefined settings.
2. Network-Attached Storage (NAS): NAS devices are dedicated storage units connected to the network. Servers can back up data to NAS using built-in backup utilities or third-party software. NAS provides centralized storage accessible by multiple servers, making it an efficient solution for backups. Many NAS devices also support RAID configurations for data redundancy.
3. Direct-Attached Storage (DAS): DAS refers to hard drives or storage arrays directly connected to servers via interfaces like SATA, SAS, or SCSI. Servers can use backup software to write data directly to DAS. DAS offers high-performance backup capabilities but may require additional management for redundancy and fault tolerance.
4. Storage Area Network (SAN): SAN is a high-speed network that connects servers to dedicated storage devices. Servers can utilize SAN technologies to back up data. SAN offers excellent performance, scalability, and advanced features like snapshots and replication. Backup software compatible with SAN infrastructure can be employed for managing and automating the backup process.
5. Cloud Storage: Servers can leverage cloud storage services like Amazon S3, Microsoft Azure Blob Storage, or Google Cloud Storage for backups. Backup software or custom scripts can transfer data securely over the network to the cloud storage provider. Cloud storage offers flexibility, scalability, and off-site data protection.
6. Virtual Tape Libraries (VTL): VTLs emulate physical tape libraries using disk-based storage. Servers can back up data to VTLs as if they were writing to actual tapes. VTLs provide faster backup and restore operations compared to traditional tape backups. The data can be replicated to off-site locations for disaster recovery purposes.

Backup methods often include incremental backups (backing up only changed or new data since the last backup), differential backups (backing up data changed since the last full backup), or full backups (copying all data). The choice of backup method depends on factors such as storage capacity, recovery time objectives, and backup frequency requirements.

It’s important to note that the specific implementation and backup software used can vary depending on the server’s operating system, hardware, and the organization’s backup strategy.