User Guide for Cisco Performance Monitor 3.2
Monitoring Load-Balancing Services
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Table Of Contents

Monitoring Load-Balancing Services

Content Switching Concepts

Monitoring Modules Collectively

Displaying CSM Usage and Activity Statistics

Displaying Load Balancing Failure Statistics

Displaying Server and Policy Reject Statistics

Monitoring Modules Individually

Displaying and Interpreting Module Detail Graphs

Displaying the Virtual Servers Table

Displaying the Real Servers Table

Displaying the Interfaces Table


Monitoring Load-Balancing Services

Load-balancing is a technology that enables network traffic to follow multiple paths to a specific destination. It distributes incoming service requests evenly among multiple servers in such a way that the load distribution is transparent to users.

Content switching is a type of server load-balancing. It balances the load of traffic across web servers based on server load and content availability.

Performance Monitor supports the monitoring of validated content-switching service modules (CSM) that are installed in Cisco Catalyst 6500 Series switches.

Note Performance Monitor does not monitor the cluster load balancing capabilities or cluster load balancing performance of Cisco VPN 3000 concentrators.

The following topics describe the features with which you monitor web server load balancing services in your network:

•Content Switching Concepts

•Monitoring Modules Collectively

•Monitoring Modules Individually

Tip To troubleshoot common problems with load-balancing services, see the Troubleshooting appendix.

Content Switching Concepts

A content switch analyzes the availability of web content and the load on web servers. Using the results of this analysis, the content switch balances the load of traffic across servers and accelerates the delivery of web content in a way that is transparent to the website end-user.

Properly-configured content switches:

•Improve the responsiveness of websites.

•Help guarantee efficient delivery of high-bandwidth files.

•Decrease network congestion.

•Optimize resource utilization in networks and servers.

•Improve the performance and scalability of web application platforms.

Purpose of Content-Switching Service Modules

A content-switching service module (CSM) provides high-performance connections between network devices and server farms based on Layer 4 through Layer 7 packet information. Clients connect to the CSM by supplying the virtual IP address (VIP) associated with the virtual server. When a client initiates a connection to the virtual server, the CSM selects a real server for the connection based on configured load-balancing algorithms and policies.

Virtual Servers

Virtual servers use real server farms through policies you configure on the CSM.

Real Servers

Real servers are physical or virtual devices assigned to a server farm. Real servers provide the services that are load balanced. When the server receives a client request, it pulls matching information from a disk and sends it to the CSM for forwarding to the client.

Server Farms

A server farm or server pool is a collection of real servers that contain the same content. You specify the server farm name when you configure the server farm and add servers to it, and when you bind the server farm to a virtual server.


Performance Monitor enables you to monitor the CSM as it tracks network sessions and server load conditions in real time and directs sessions to the most appropriate servers.

Monitoring Modules Collectively

The following topics explain how you can monitor CSM modules collectively:

•Displaying CSM Usage and Activity Statistics

•Displaying Load Balancing Failure Statistics

•Displaying Server and Policy Reject Statistics

Displaying CSM Usage and Activity Statistics

You can display usage and activity statistics for all of the validated CSM modules in your network.

Procedure

Step 1 Select either:

•Monitor > Load Balancing.

•Monitor > Load Balancing > Modules.

All measured values on the Load Balancing Modules page are computed as deltas (meaning they indicate the scope of difference from one polling cycle to the next)—except for the whole number count of current connections.

Step 2 (Optional) To display detail graphs for one CSM module, click the relevant entry in the Chassis:Module column.

Table 3-3 on page 3-9 describes other optional tasks that recur throughout the GUI.

Displaying Load Balancing Failure Statistics

You can display and work from a table that describes the operational failures of your validated CSM modules.

Procedure

Step 1 Select Monitor > Load Balancing > Failures.

All measured values on the Load Balancing Failures page are computed as deltas.

Step 2 (Optional) To display summary graphs for one CSM module, click the relevant entry in the Chassis:Module column.

Table 3-3 on page 3-9 describes other optional tasks that recur throughout the GUI.

Displaying Server and Policy Reject Statistics

You can display and work from a table of rejection statistics for your validated CSM modules.

Procedure

Step 1 Select Monitor > Load Balancing > Rejects.

All measured values on the Load Balancing Rejects page are computed as deltas.

Step 2 (Optional) To display summary graphs for one CSM module, click the relevant entry in the Chassis:Module column.

Table 3-3 on page 3-9 describes other optional tasks that recur throughout the GUI.

Monitoring Modules Individually

The following topics explain how you can monitor CSM modules individually:

•Displaying and Interpreting Module Detail Graphs

•Displaying the Virtual Servers Table

•Displaying the Real Servers Table

•Displaying the Interfaces Table

Displaying and Interpreting Module Detail Graphs

You can display and work from a page of detail graphs for one validated CSM module.

Procedure

Step 1 Select Monitor > Load Balancing > Module Details.

By default, Performance Monitor displays graphs that describe the health and performance of whichever module uses the lowest number as its IP address (Table 8-1).

Step 2 (Optional) To view equivalent graphs for a different CSM module, select the relevant IP address and slot number from the Select Chassis: Module list.

Table 3-3 on page 3-9 describes other optional tasks that recur throughout the GUI.

Table 8-1 Interpreting Load Balancing Module Graphs 

Label
Description

Connection Failures

Illustrates the trend of module connection failures over time:

•The vertical axis shows the percentage of failures in a specific polling cycle.

•The horizontal axis shows the time of day for the polling cycle.

Dropped Connection

Illustrates the trend of dropped connections over time:

•The vertical axis shows the average number of dropped connections in a specific polling cycle.

•The horizontal axis shows the time of day for the polling cycle.

Current Connections

Illustrates the trend of successful connections over time:

•The vertical axis shows the average number of successful connections in a specific polling cycle.

•The horizontal axis shows the time of day for the polling cycle.

Total Rejects

Illustrates the trend of rejected connections over time:

•The vertical axis shows the average sum of these values over time:

–The number of connections that were rejected because the relevant server farm had no active servers.

–The number of connections that were rejected because they failed to match any configured policy.

–The number of connections that were rejected because the matching virtual server was not configured with any policy.

•The horizontal axis shows the time of day for the polling cycle.


Displaying the Virtual Servers Table

You can display and work from a table of virtual server statistics for one validated CSM module.

Procedure

Step 1 Select Monitor > Load Balancing > Virtual Servers.

The Load Balancing Virtual Servers page displays information about all of the virtual servers associated with a specific CSM module.

Step 2 (Optional) To display equivalent data for a different CSM module, select the relevant IP address and slot number from the Select Chassis:Module list.

Table 3-3 on page 3-9 describes other optional tasks that recur throughout the GUI.

Displaying the Real Servers Table

You can display and work from a table of real server statistics for one validated CSM service module.

Procedure

Step 1 Select Monitor > Load Balancing > Real Servers.

The Load Balancing Real Servers page displays information about all of the real servers associated with a specific CSM module.

These values are calculated as deltas:

•No. Total Connections.

•No. Total Failed Connections.

•Connection Failed %.

Step 2 (Optional) To display equivalent data for a different CSM module, select the relevant IP address and slot number from the Select Chassis:Module list.

Table 3-3 on page 3-9 describes other optional tasks that recur throughout the GUI.

Displaying the Interfaces Table

You can display and work from a table of interface statistics for one validated CSM module.

Procedure

Step 1 Select Monitor > Load Balancing > Interfaces.

Statistics on the Load Balancing Interfaces page describe routed VLANs associated with a CSM module interface.

Note Performance Monitor displays information for routed VLANs that are associated with the CSM module.

All measured values on the Load Balancing Interfaces page are computed as deltas.

Step 2 (Optional) To display equivalent data for a different CSM module, select the relevant IP address and slot number from the Select Chassis:Module list.

Table 3-3 on page 3-9 describes other optional tasks that recur throughout the GUI.