title: How to destroy a ZFS pool while the pool is busy?
body: <p>I have zfs pool:</p>
  
  <pre><code>$ sudo zpool status lxd
    pool: lxd
   state: ONLINE
    scan: none requested
  config:
  
      NAME                    STATE     READ WRITE CKSUM
      lxd                     ONLINE       0     0     0
        /var/lib/lxd/zfs.img  ONLINE       0     0     0
  </code></pre>
  
  <p>I've tried: </p>
  
  <pre><code>$ sudo zpool destroy -f lxd 
  cannot destroy 'lxd': pool is busy
  </code></pre>
  
  <p>How can I unmount zpool img</p>