sflow: Avoid division by zero if sampling rate is 0.

[openvswitch] / vswitchd / ovs-vswitchd.conf.5.in

diff --git a/vswitchd/ovs-vswitchd.conf.5.in b/vswitchd/ovs-vswitchd.conf.5.in
index c41667868108bf3fc8ab975b7b8adca5d317068f..c53c4d4d5c9c390f03e719a830fd184e2b10b4bf 100644 (file)
--- a/vswitchd/ovs-vswitchd.conf.5.in
+++ b/vswitchd/ovs-vswitchd.conf.5.in
@@ -459,6 +459,29 @@ netflow.mybr.host=nflow.example.com:9995
 
 .fi
 .RE
 
 .fi
 .RE

+.SS "sFlow Monitoring"
+sFlow(R) is a protocol for monitoring switches.  A bridge may be
+configured to send sFlow records to sFlow collectors by defining the
+key \fBsflow.\fIbridge\fB.host\fR for each collector in the form
+\fIip\fR[\fB:\fIport\fR].  Records from \fIbridge\fR will be sent to
+each \fIip\fR on UDP \fIport\fR.  The \fIip\fR must be specified
+numerically, not as a DNS name.  If \Iport\fR is omitted, port 6343 is
+used.
+.PP
+By default, 1 out of every 400 packets is sent to the configured sFlow
+collector.  To override this, set \fBsflow.\fIbridge\fB.sampling\fR to
+the number of switched packets out of which 1, on average, will be
+sent to the sFlow collector, e.g. a value of 1 sends every packet to
+the collector, a value of 2 sends 50% of the packets to the collector,
+and so on.
+.PP
+\fBovs\-vswitchd\fR also occasionally sends switch port statistics to
+sFlow collectors, by default every 30 seconds.  To override this, set
+\fBsflow.\fIbridge\fB.polling\fR to a duration in seconds.
+.PP
+By default, \fBovs\-vswitchd\fR sends the first 128 bytes of sampled
+packets to sFlow collectors.  To override this, set
+\fBsflow.\fIbridge\fB.header\fR to a size in bytes.

 .SS "Remote Management"
 A \fBovs\-vswitchd\fR instance may be remotely managed by a controller that
 supports the OpenFlow Management Protocol, such as NOX.  This
 .SS "Remote Management"
 A \fBovs\-vswitchd\fR instance may be remotely managed by a controller that
 supports the OpenFlow Management Protocol, such as NOX.  This


@@ -514,7 +537,7 @@ switch will perform all configured bridging and switching locally.
 .TP
 \fBdiscover\fR
 Use controller discovery to find the local OpenFlow controller.
 .TP
 \fBdiscover\fR
 Use controller discovery to find the local OpenFlow controller.

-Refer to \fB\ovs\-openflowd\fR(8) for information on how to configure a DHCP
+Refer to \fBovs\-openflowd\fR(8) for information on how to configure a DHCP

 server to support controller discovery.  The following additional
 options control the discovery process:
 .
 server to support controller discovery.  The following additional
 options control the discovery process:
 .