Data recovery - Hard Disk Repair and File Recovery

A RAID system supports different types of configurations such as 0, 1, 4, 5 and lineal. The characteristics are as follows:

Level 0 – This level is also known as “striping” because the information saved in the hard drive is divided into groups, and the data is written in all the drives that compose the unit. The storage capacity is the same as of one hard drive, and the failure of one hard drive will constitute inaccessibility to the information.

Level 1 - This level is best known as “replica”. Here, the system duplicates and stores the information in more that one place. Therefore, it is still possible to recover the files in the event that one disc failed completely. RAID 1 writes identical information in each disc of the unit; thus, keeping several copies that can help retrieve any data.

Level 4 – This system uses (bandas de paridad) FAT (file allocation tables) to protect the data. The storage capacity on this level equals to the total capacity of all drives minus the capacity of each one.

Level 5 – This is the most popular and widely used system because it distributes the tables among all the drives in the unit. It also eliminates LOS CUELLOS DE BOTELLA generated in RAID 4. The only cuello de botella would be the process in which the tables are calculated. The storage capacity on this level equals to the total capacity of all drives minus the capacity of each one.

Lineal RAID – This system is composed of a group of hard drives of equal or different capacities to create a virtually bigger unit. The information is stored in sequential order, and it is stored on the next
drive once the prior has been filled. Unfortunately, the reliability factor of this system is rather sparse. If one of the hard drives fails, the other drives can not be used as a back up to retrieve the information. The capacity equals to the total capacity of all the hard drives as a group.