To create a mirrored pool, use the mirror keyword, followed by any number of storage devices that will comprise the mirror. Multiple mirrors can be specified by repeating the mirror keyword on the command line. The following command creates a pool with two, two-way mirrors:
# zpool create tank mirror c1d0 c2d0 mirror c3d0 c4d0 |
The second mirror keyword indicates that a new top-level virtual device is being specified. Data is dynamically striped across both mirrors, with data being redundant between each disk appropriately.
For more information about recommended mirrored configurations, see the following site:
http://www.solarisinternals.com/wiki/index.php/ZFS_Best_Practices_Guide
Currently, the following operations are supported on a ZFS mirrored configuration:
Adding another set of disks for an additional top-level vdev to an existing mirrored configuration. For more information, see Adding Devices to a Storage Pool.
Attaching additional disks to an existing mirrored configuration. Or, attaching additional disks to a non-replicated configuration to create a mirrored configuration. For more information, see Attaching and Detaching Devices in a Storage Pool.
Replacing a disk or disks in an existing mirrored configuration as long as the replacement disks are greater than or equal to the device to be replaced. For more information, see Replacing Devices in a Storage Pool.
Detaching a disk in a mirrored configuration as long as the remaining devices provide adequate redundancy for the configuration. For more information, see Attaching and Detaching Devices in a Storage Pool.
Currently, the following operations are not supported on a mirrored configuration:
You cannot outright remove a top-level device from a mirrored storage pool. An RFE is filed for this feature.