This is mandatory when defining a volume. <span class="since">Since 0.4.1</span></dd>
<dt><code>key</code></dt>
<dd>Providing an identifier for the volume which is globally unique.
- This is optional when defining a volume, a key will be generated if
- omitted. <span class="since">Since 0.4.1</span></dd>
+ This cannot be set when defining a pool: it is always generated.
+ <span class="since">Since 0.4.1</span></dd>
<dt><code>allocation</code></dt>
<dd>Providing the total storage allocation for the volume. This
may be smaller than the logical capacity if the volume is sparsely