RAID 1: mirror RAID
RAID 1 (mirroring) duplicates data across all drives for maximum security. SOS Data Recovery recovers your RAID 1 data with a free 3-hour diagnosis.
How does RAID 1 work?
The operation of RAID 1 is based on the principle of data redundancy. When configuring a RAID 1, you need at least two hard drives. This configuration mode ensures an exact copy of the data on each hard drive in the RAID. This means that each bit, each file, and each data element are replicated and stored simultaneously on all the hard drives.
RAID 1 offers great security and data reliability. In the event of a hard drive failure, the data remains accessible and fully available on the remaining hard drive. This data redundancy provides protection against data loss due to hardware failures. When a hard drive fails, RAID 1 automatically switches to the functional hard drive, allowing uninterrupted access to the data.
However, it is important to note that RAID 1 does not offer significant performance improvements in terms of data access or write speed compared to a single hard drive. Since all data is written simultaneously on each hard drive in the RAID 1, the write time is doubled compared to a single hard drive. Similarly, data access is not faster than a traditional hard drive.
The main advantage of RAID 1 lies in its resilience and ability to protect data against hardware failures. It is an ideal solution for users and businesses that prioritize data security and continuous availability. In the event of a hard drive failure, rebuilding the RAID 1 by replacing the faulty drive is relatively simple and quick, minimizing downtime.
In summary, RAID 1 ensures complete data redundancy by replicating it on all hard drives in the RAID. This guarantees high data security but does not provide significant gains in terms of access speed or write speed. RAID 1 is particularly suitable for environments where data protection is crucial, such as file servers, databases, and systems requiring high availability.
SOS Data Recovery, a Swiss laboratory based in Ins, has been recovering data from all RAID systems since 2006. Over 11,300 media processed for more than 8,000 clients. Free diagnosis within 3 hours. CyberSafe certified.
What are the common failures of RAID 1?
Do you recognise one of these situations? Contact us for a free diagnosis.
Simultaneous failure of both mirrors
If both drives in the mirror fail simultaneously — power surge, identical wear — data becomes inaccessible. Common with drives from the same batch.
Mirror desynchronisation
The mirror desynchronises after a power cut or hard crash. The controller no longer knows which drive contains the most recent version of the data.
Failed rebuild
Replacing a failed drive triggers a rebuild that fails: the remaining drive has bad sectors revealed under the intensive load of reconstruction.
Loss of controller configuration
Empty BBU battery, corrupted firmware or accidental reset. The mirror volume is no longer recognised despite physically functional drives.
Accidental deletion or formatting
In RAID 1, a format or deletion is written instantly to both mirrors. Redundancy does not protect against human or logical errors.
Ransomware and software corruption
Ransomware encrypts data simultaneously on both mirror drives. RAID 1 redundancy offers no protection against software attacks.