+When multiple controllers are configured, \fBovs\-openflowd\fR
+connects to all of them simultaneously. OpenFlow 1.0 does not specify
+how multiple controllers coordinate in interacting with a single
+switch, so more than one controller should be specified only if the
+controllers are themselves designed to coordinate with each other.
+(The Nicira-defined \fBNXT_ROLE\fR OpenFlow vendor extension may be
+useful for this.)
+.PP