My journey with Btrfs – Part 2 – Concentration Enhancing Menu Initialiser

This is part two of my journey with btrfs where I’m going on a quest for reliable and robust storage.

In the last post I had a raid 5 Btrfs with two 2TB hard-drives. I was a bit surprised because Btrfs behaved like a raid 1 but reported storage of a raid 0.

I’ve just realized that I didn’t explain what RAID was. RAID stands for Redundant Array of Independent Disks. The different level of RAID describe how the data are stored, whether or not it’s failure proof.

I’ll just explain the most common RAID used.

  • RAID 0: use all your disk to act as one. There is no redundancy to speak of. If one of your drive fails, your entire array fail.
  • RAID 1: use half of the devices you give it as a mirror for your data.
  • RAID 5: spread data among the hard drives, if one drives fail it can still restore it using the data from others drives.

Those explanation are simplifications, each type of raid as its advantage and disadvantage. RAID 5 is, like RAID 1, failure proof against the loss of one hard-drive.

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My journey with Btrfs part 1

Btrfs is a new file system for Linux. A file system is used to manage how files are stored in a computer. Btrfs goal is to provide advanced features such as pooling or snapshot with a focus on fault tolerance, repair and easy administration.

I possess at home a NAS, which contains all my data. But this data is stored on several hard-drives, each being totally separate. And if one of them were to die tomorrow the data stored on it would be lost. With Btrfs I will be able to combine my hard-drives to show up as a single one. I could add more storage in the future and if one them end up dying I should be able to restore the lost data.

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