ovs-openflowd: Fix support for multiple controllers.

[sliver-openvswitch.git] / utilities / ovs-openflowd.8.in

diff --git a/utilities/ovs-openflowd.8.in b/utilities/ovs-openflowd.8.in
index 47af872..689ff5c 100644 (file)
--- a/utilities/ovs-openflowd.8.in
+++ b/utilities/ovs-openflowd.8.in
@@ -19,12 +19,21 @@ to relay.  It takes one of the following forms:
 .so lib/dpif.man
 .
 .PP
-The optional \fIcontroller\fR arguments specify how to connect to
-the OpenFlow controller.  It takes one of the following forms:
+The optional \fIcontroller\fR arguments specify how to connect to the
+OpenFlow controller or controllers.  Each takes one of the following
+forms:
 .
 .so lib/vconn-active.man
 .
 .PP
+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
 If no \fIcontroller\fR is specified, \fBovs\-openflowd\fR attempts to
 discover the location of a controller automatically (see below).
 .