This article explains how to expand a ZFS Pool. I have used this procedure a few times while dealing with FreeBSD in a virtual environment where I have needed to expand a zpool.

  • Enable the “autoexpand” feature on the zpool

    zpool set autoexpand=on zfstestpool

  • Shutdown the system

    shutdown -h now

  • Resize the gpt partition

    gpart resize -i 1 /dev/da1

  • Export the zpool

    zpool export zfstestpool

  • Import the zpool

    zpool import zfstestpool

  • “Online” the zpool which will automatically expand it to partition boundaries

    zpool online zfstestpool /dev/da1p1

  • “df -hl /mountpoint” should now show that the zpool has been expanded