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I'm still new with FreeNas and RAID system.
I successfully make a file server with FreeNAS with 2 TB of Harddrive formated with ZFS.
Now i want to make it RAID 1, by adding another 1, 2TB Harddrive.
What i want to ask, if this possible? adding another Harddrive in installed and configured FreeNas?


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up vote 1 down vote accepted

ZFS does not support a "reshape" operation of any kind, so you cannot take your existing drive and convert it into being in a mirror pair (the ZFS term for RAID1).

However, what you can do is to add the new disk to the pool normally (not in a RAID-type pair), but then set copies=2, forcing files to be stored across multiple disks to provide the same level of data protection.

zfs set copies=2 poolname

Note that the new copies policy only applies to newly written data; you'll need to get the extra copies written to the second disk by re-writing them (potentially via a zfs send then zfs recv).

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Thanks Shane. I have clear understanding now. – Ivan Jun 6 '12 at 6:45

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