Viewing Tunnel Statistics

The Tunnels page summarizes the overall inbound and outbound traffic statistics for the tunnels since the last reboot. The Tunnels table condenses the total LAN and WAN counters.

When you select a tunnel from the table, the Appliance Manager provides the following detailed report:

Name	Description
LAN/WAN Statistics	• Specifies the number of bytes and packets received, processed, and transmitted by a Silver Peak tunnel in both the outbound (LAN-to-WAN) and inbound (WAN-to-LAN) directions. • Statistics are separated for inbound and outbound traffic.
Flows/Latency/ Packet Correction Statistics	• Specifies packets by TCP flow versus non-TCP flow. Packets in a TCP flow are further sorted by whether or not they’re accelerated. • Displays round trip latency time in milliseconds (minimum, maximum, and average). • Displays how many received packets were lost before and after Forward Error Correction (FEC). • Displays how many received packets were out-of-order before and after Packet Order Correction (POC). • Statistics represent combined, bi-directional data.

The Appliance Manager reports all realtime tunnel statistics as raw data.

w	To view a specific tunnel’s detailed statistics

Click the tunnel’s Name. Typically, the following displays:

The Appliance Manager organizes an individual tunnel’s statistics into two parts:

n	LAN/WAN Statistics

n	Flows / Latency / Packet Correction Statistics

LAN/WAN Statistics

The LAN/WAN Statistics summarize realtime data directly related to the Silver Peak tunnel’s processing.

These statistics answer the following questions:

n	For any given tunnel, how many bytes (or packets) did the tunnel receive and subsequently transmit?

n	Which tunnels have processed the most traffic? The least traffic?

n	What error types and quantities were encountered for traffic inbound from the WAN?

n	What error types and quantities were encountered for traffic inbound from the LAN?

The LAN/WAN Statistics area displays the following information:

Section	Field	Definition
LAN Rx (outbound traffic)	Rx Bytes	Number of bytes received from the LAN.
	Rx Pkts	Number of packets received from the LAN.
WAN Tx (outbound traffic)	Tx Bytes	Number of bytes sent to the WAN.
	Tx Pkts	Number of packets sent to the WAN.
LAN Tx (inbound traffic)	Tx Bytes	Number of bytes sent to the LAN.
	Tx Pkts	Number of packets sent to the LAN.
WAN Rx (inbound traffic)	Rx Bytes	Number of bytes received from the WAN.
	Rx Pkts	Number of packets received from the WAN.

Flows / Latency / Packet Correction Statistics

The Flows / Latency / Packet Correction Statistics area includes other general statistics. It answers the questions:

n	How many of the traffic flows are based on TCP and how many are not?

n	How much of the TCP flow was accelerated?

n	What is the minimum, average, and peak latency in milliseconds?

n	How many packets were lost before Forward Error Correction (FEC), and how many were lost after?

n	How many out-of-order packets were there before and after Packet Order Correction?

TCP Flow / Latency / Packet Loss Statistics area displays the following statistics:

Section	Field	Definition
Traffic Flows	Non-TCP Flows	Number of flows that are not TCP-based.
	TCP Flows	Number of flows that are TCP-based.
	TCP Accel Flows	Number of TCP flows that are accelerated. Since CIFS acceleration is a subset of TCP acceleration, they are included herein.
	TCP Non-Accel Flow	Number of TCP flows that are not accelerated.
Round Trip Latency	Average	Length of the average round trip latency, in milliseconds.
	Maximum	Length of the peak round trip latency, in milliseconds.
	Minimum	Length of the shortest round trip latency, in milliseconds.
Rx Packet Correction	Pre FEC Loss	Number of packets lost before Forward Error Correction (FEC).
	Post FEC Loss	Number of packets lost after Forward Error Correction (FEC).
	Pre POC Out-of-Order	Number of out-of-order packets before Packet Order Correction (POC).
	Post POC Out-of-Order	Number of out-of-order packets after Packet Order Correction (POC).

Fine-tuning Packet Correction

Enabling Forward Error Correction (FEC) in the tunnel configuration can sometimes result in the creation of additional Out-of-Order Packets (OOP).

To view the performance after enabling FEC, do either of the following:

n	Access the Monitoring > Tunnels page and review the Delta Stats for Pre POC Out-of-Order and Post POC Out-of-Order.

n	Access the Monitoring > Charts page, select the tunnel from Traffic, and review its Out-of-Order chart.

Adjust if necessary, as follows:

1	If out-of-order packets exist, then you’ll need to try another Reorder Wait time for the tunnel in question.

2	Go to Configuration > Tunnels, and in the row of the tunnel in question, click Advanced Tunnel.

3	At first, set the Reorder Wait time to 10ms, and save the configuration.

4	Return to the stats page(s) to see if the out-of-order packets have been eliminated.

5	If there are still out-of-order packets, then go back to the tunnel configuration and increase the Reorder Wait time.

6	Repeat Steps 5 and 6 until there are no more out-of-order packets.

Please send comments or suggestions regarding user documentation to techpubs@silver-peak.com.