Explain Block Level Storage Virtualization and File Level Storage Virtualization(or different types of storage virtualization).

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  Block-Level Storage Virtualization

Block-level storage is a form of storage that is extensively used in Storage Area Networks (SANS) and other large-scale storage systems by big corporations and companies. A block-level storage system allows each block to be handled as an independent hard drive, and the blocks are handled by a server operating system.

Storage at the block level Virtualization is a storage solution that offers applications and users a flexible, logical arrangement of storage capacity while abstracting its physical location. It intercepts I/O requests to that logical capacity as a software layer and translates them to the relevant physical locations. As a result, virtualization enables administrators to supply storage capacity when and where it is required while shielding users from potentially disruptive aspects like expansion, data protection, and system maintenance.

  • Block-level storage is usually deployed in the SAN environment. 
  • Block-level storage offers boot-up of systems that are connected to them.
  • Block-level storage can be used to store files and can work as storage for special applications like databases, Virtual machine file systems, and so on. 
  • Block-level storage data transportation is more efficient and reliable.
  • Block-level storage supports individual formatting of file systems like NFS, NTFS, and VMFS (VMware) which are required by the applications. 

Each storage volume can be treated as an independent disk drive, and it can be controlled by an external server operating system. 

In terms of administrative complexity, block-based storage systems are more difficult than file-based storage systems; this is the price you pay for the extra flexibility. 

Administrators of block storage devices must:

  • Carefully manage and distribute storage on a per-server basis. Control storage security levels (i.e., RAID).
  • Track storage device performance to verify that it continues to satisfy the demands of the server and applications. 
  • Manage and keep an eye on the storage communications infrastructure.

This block-level shared storage is used by a variety of applications, including: 

1. Databases - When clustering the databases, the clustered databases require shared storage. 

2. Exchange - Despite significant advancements to Exchange, Microsoft still does not offer file-level or network-based storage. Only block-level storage is available.

3. VMware - Although VMware may utilize file-level storage using Network File System (NFS), it is far more typical to install VMware servers with shared VMFS volumes on block-level storage. 

4. Server boot - Servers can be configured to boot from block-level storage with the correct storage device.


File-level Storage Virtualization

File virtualization is a type of storage virtualization that works at the computer file level. It entails combining various storage devices into a single logical file pool. The establishment of an abstraction layer between file servers and the clients that use those file servers is referred to as file virtualization. Once installed, the file virtualization layer maintains files and file systems across servers, allowing administrators to provide clients with a single logical file mount for all servers. File data and metadata are still stored on the file servers.

While this setup may appear to add unnecessary IT complexity, file virtualization offers numerous major benefits, including a global namespace for indexing files on network file servers. Furthermore, this virtual file storage consolidation enables the sharing of surplus storage space among file servers. Data migrations across file servers may be performed invisibly to end-users and applications, which is suitable in a tiered storage environment.

In a nutshell, file virtualization enables businesses to have access to separated storage space on network file servers and execute smooth file migrations between them. File virtualization can be implemented as an appliance or as a commercially available server running file virtualization software. The decision is usually influenced by the expense as well as the amount of management and disruption involved.

  • File-level storage is simple to use and implement.
  • It stores files and folders, and the visibility is the same to the clients accessing and to the system which stores it.
  • This level of storage is inexpensive to be maintained when it is compared to its counterpart ie. block-level storage.
  • Network-attached storage systems usually depend on this file-level storage. 
  • File-level storage can handle access control, integration with corporate directories; and so on.

Scalability, which might include the number of file systems, files, servers, or 1/O performance, might restrict file virtualization. To function with existing storage systems and switches, the file virtualization platform must be compatible with the present infrastructure. A file virtualization platform should always be validated for proper scalability and compatibility to avoid potential issues.

File-level use cases include:

Mass File Storage: When your customers only require a location to save data, file-level devices can be quite useful.

VMware: In addition to block-level storage, VMware hosts may connect to the storage offered through NFS.





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