any defined controllers forever.</dd>
</dl>
</p>
- <p>If this value is unset, the default is implementation-specific.</p>
+ <p>
+ The default is <code>standalone</code> if the value is unset, but
+ future versions of Open vSwitch may change the default.
+ </p>
+ <p>
+ The <code>standalone</code> mode can create forwarding loops on a
+ bridge that has more than one uplink port unless STP is enabled. To
+ avoid loops on such a bridge, configure <code>secure</code> mode or
+ enable STP (see <ref column="stp_enable"/>).
+ </p>
<p>When more than one controller is configured,
<ref column="fail_mode"/> is considered only when none of the
configured controllers can be contacted.</p>