NAME

     zpool-add — add vdevs to ZFS storage pool

SYNOPSIS

     zpool add [-fgLnP] [--allow-in-use --allow-replication-mismatch --allow-ashift-mismatch] [-o
           property=value] pool vdev…

DESCRIPTION

     Adds the specified virtual devices to the given pool.  The vdev specification is described
     in the Virtual Devices section of zpoolconcepts(7).  The behavior of the -f option, and the
     device checks performed are described in the zpool create subcommand.

     -f      Forces use of vdevs, even if they appear in use, have conflicting ashift values, or
             specify a conflicting replication level.  Not all devices can be overridden in this
             manner.

     -g      Display vdev, GUIDs instead of the normal device names.  These GUIDs can be used in
             place of device names for the zpool detach/offline/remove/replace commands.

     -L      Display real paths for vdevs resolving all symbolic links.  This can be used to look
             up the current block device name regardless of the /dev/disk path used to open it.

     -n      Displays the configuration that would be used without actually adding the vdevs.
             The actual pool creation can still fail due to insufficient privileges or device
             sharing.

     -P      Display real paths for vdevs instead of only the last component of the path.  This
             can be used in conjunction with the -L flag.

     -o property=value
             Sets the given pool properties.  See the zpoolprops(7) manual page for a list of
             valid properties that can be set.  The only property supported at the moment is
             ashift.

     --allow-ashift-mismatch
             Disable the ashift validation which allows mismatched ashift values in the pool.
             Adding top-level vdevs with different sector sizes will prohibit future device
             removal operations, see zpool-remove(8).

     --allow-in-use
             Allow vdevs to be added even if they might be in use in another pool.

     --allow-replication-mismatch
             Allow vdevs with conflicting replication levels to be added to the pool.

EXAMPLES

   Example 1: Adding a Mirror to a ZFS Storage Pool
     The following command adds two mirrored disks to the pool tank, assuming the pool is already
     made up of two-way mirrors.  The additional space is immediately available to any datasets
     within the pool.
           # zpool add tank mirror sda sdb

   Example 2: Adding Cache Devices to a ZFS Pool
     The following command adds two disks for use as cache devices to a ZFS storage pool:
           # zpool add pool cache sdc sdd

     Once added, the cache devices gradually fill with content from main memory.  Depending on
     the size of your cache devices, it could take over an hour for them to fill.  Capacity and
     reads can be monitored using the iostat subcommand as follows:
           # zpool iostat -v pool 5

SEE ALSO

     zpool-attach(8), zpool-import(8), zpool-initialize(8), zpool-online(8), zpool-remove(8)