RAID 1 with two 4 TB drives: simple mirroring, real redundancy, and read-speed gains
RAID 1 is the safe, simple default for two-drive setups where data integrity matters more than capacity. 50% overhead stings at higher drive counts, but for a basic home NAS or a workstation boot drive, it gives peace of mind without complexity.
RAID 1 with two 4 TB drives mirrors all data identically across both disks, giving you 4 TB of usable capacity from 8 TB of raw storage. This is the simplest form of redundancy: if one drive fails, the other keeps running with zero data loss and zero downtime. You replace the failed drive, the array rebuilds, and you never lose access to your files.
By TechCompare · Updated
How this is calculated
RAID 1 costs you 50% of your raw capacity but gives you the strongest single-drive fault tolerance of any RAID level. Read performance improves because the controller can read from both drives simultaneously (theoretically 2× read speed). Write performance stays at single-drive speed because every write must go to both disks. For home NAS users storing family photos and documents, a pair of 4 TB drives in RAID 1 is often the right answer: simple, fast to rebuild, and universally supported by every motherboard, NAS, and RAID card made in the last 20 years.
Verdict
RAID 1 is the safe, simple default for two-drive setups where data integrity matters more than capacity. 50% overhead stings at higher drive counts, but for a basic home NAS or a workstation boot drive, it gives peace of mind without complexity.
More RAID scenarios
Frequently asked questions
Does RAID 1 protect against file corruption or ransomware?
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