Table Of Contents

Path Analysis

Overview

Layer 3 Path Analysis

Layer 2 Path Analysis

Layer 2 Shortcuts

Understanding Path Analysis

Path Analysis Requirements

Using Path Analysis Legend

Setting Up Path Analysis

Path Analysis Main Window

Path Analysis Commands

User-Configurable Options

Understanding Path Analysis Toolbar

Understanding End-Point Specification Panel

Exploring Trace Results Tabbed Panel

Trace Results Tab View Advantages and Disadvantages

Understanding Map Display

Understanding Tooltips in Map Display

Understanding Trace Display

Understanding Table Display

Understanding Status Bar

Mapping Subnet to VLAN/ELAN

Understanding VLAN/ELAN Subnet Mapping Table

Editing VLAN/ELAN Subnet Mapping Table

Displaying Previously Supplied Manual Mappings

Displaying Auto-Discovered Mappings

Displaying All Known Subnet Mappings

Erasing Previously Supplied Manual Mappings

Modifying Subnet Mapping Table

Clearing Local Entries

Clearing All Entries

Verifying Need for Manual Entry

Verifying Subnet Mapping Table Entries

Using Subnet Mapping Table for Layer 3 Traces

Using Subnet Mapping Table for Layer 2 Traces

Understanding Traces

Beginning New Trace

Discovering Networks

Specifying Valid Points

Starting and Stopping Traces

Monitoring Trace in Progress

Understanding Status Bar Messages

Understanding Alert Messages

Layer 2 and Layer 3 Path Trace Errors

Understanding Lines in Map View

Understanding Icons in Map View

Reversing Traces

Saving Traces

Displaying Saved Traces

Displaying User Archived Traces

Tracing Voice Over IP Traffic

Understanding Voice Trace Window

Performing Voice Over IP Trace

Tracing From IP Phone to Cisco CallManager

Tracing From Gateway to Cisco CallManager

Tracing Completed Calls

Tracing Call in Progress

Tracing Potential Calls

Enabling CDR Logging in Cisco CallManager

Understanding CDR Query Status Log

Understanding Called Number Matching

Understanding Called Time Matching

Understanding Calling Number Matching

Using Path Analysis With Other Applications

Displaying Path in Topology Services

Starting CiscoView

Starting Telnet

Starting Visual Switch Manager

Troubleshooting Path Analysis

Frequently Asked Questions

Troubleshooting Suggestions (Data)

Troubleshooting Suggestions (Voice)

Path Analysis

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Path Analysis is an operations and diagnostic application that traces the connectivity between two specified devices on your network, including the physical and logical paths taken by packets flowing between those points. This chapter contains:

•Overview

•Understanding Path Analysis

•Using Path Analysis Legend

•Setting Up Path Analysis

•Path Analysis Main Window

•Mapping Subnet to VLAN/ELAN

•Understanding Traces

•Tracing Voice Over IP Traffic

•Using Path Analysis With Other Applications

•Troubleshooting Path Analysis

Overview

Path Analysis displays Layer 2 and Layer 3 pathways in your network. These are the logical and physical paths that packets take between Cisco devices (including voice-enabled devices) and the shortcut connections where packets are IP-switched.

You can use Path Analysis to:

•Analyze paths between two specified Layer 2 or Layer 3 devices using device names or IP addresses, and show results visually in a network view, table, or textual trace display.

•Highlight Layer 2 and Layer 3 paths in the Topology Services network view.

•Display Layer 3 paths between two specified devices in the managed domain. Also where possible, display the Layer 2 path between two specified end-user hosts known to User Tracking.

•Display information about interface properties such as Maximum Transmission Unit (MTU) size, speed, MAC address, and media type.

•Display information about device properties such as node name, device type, chassis type, up-time, and one alias.

•Trace the paths that Voice over IP (VoIP) traffic takes on data networks.

•Save and print path trace information.

•Run CiscoView from supported devices displayed in the Path Analysis view.

•Run Visual Switch Manager from Cisco 1900, Cisco 2900XL, and Cisco 3500XL devices displayed in the Path Analysis view.

•Start Telnet (remote terminal) connections with the Cisco Systems Console from supported devices displayed in the Path Analysis view.

While Layer 2 paths are displayed only where they exist, and where they can be determined, Layer 3 paths are always displayed. For more details see Layer 3 Path Analysis, Layer 2 Path Analysis

Layer 3 Path Analysis

The Layer 3 path is the logical path on the network that packets follow through Cisco devices such as routers. Layer 3 is also called the network layer. It represents the network at the IP level. The Layer 3 path displays the end-points and routers on the network.

Layer 3 output from Path Analysis is similar to the output of UNIX and Microsoft Windows traceroute command, but is more detailed.

Path Analysis supports only the IP protocol; AppleTalk and IPX are not supported. Layer 3 tracing does not support PCs or workstations with more than one network adapter.

Layer 2 Path Analysis

The Layer 2 path is the physical path on the network that packets follow through Cisco devices. Path Analysis cannot always determine the Layer 2 path for every Layer 3 hop.

The Layer 2 path includes devices that are either:

•Simple Network Management Protocol (SNMP) accessible and known through Topology Services.

Or

•SNMP inaccessible but have been discovered by User Tracking (for example, end-user hosts).

The Layer 2 path provides further resolution of the Layer 3 path, but is not necessarily a complete representation of all Layer 2 devices. For example, hubs or other devices that do not support the Cisco Discovery Protocol (CDP) do not appear in Layer 2 traces.

Path Analysis uses Campus Manager Server information to build Layer 2 paths, combining:

•Network topology information

•Virtual LAN (VLAN) and Emulated LAN (ELAN) information

•User and host information

•Current LAN spanning tree configuration

Path Analysis supports Layer 2 tracing on Ethernet, Fast Ethernet, Gigabit Ethernet, and LAN Emulation (LANE) networks.

LANE support includes tracing the path inside an ATM cloud. For this release, Path Analysis Layer 2 tracing does not support FDDI, Token Ring, and WAN interfaces, or router bridge groups.

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Tip If the Layer 2 trace succeeds, the Highlight Path in Network View command is enabled in the toolbar and in the Action menu. See Path Analysis Commands.

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Layer 2 Shortcuts

Shortcut connections occur in the Layer 2 path where packets are IP-switched after the router has determined the next-hop destination. They appear in the Layer 2 path as connections between switch ports that bypass intervening routers.

Currently, the only shortcuts reported are those provided by the Cisco Catalyst 5000 switches.

You can recognize shortcuts in the Map display either:

•Where shortcuts exist and the Layer 2 path is known, the shortcutting switches are highlighted in blue and connected by an arrow.

Or

•Where shortcuts exist but the Layer 2 path is unknown, the recognized shortcutting switch is highlighted in blue.

Understanding Path Analysis

Path Analysis consists of two main components:

•Path Analysis client that displays Layer 2 and Layer 3 pathways in your network.

•Path Analysis Service Module — Resides on the CiscoWorks Server and responds to Path Analysis client requests.

For more details, see sections Understanding Trace Display and Exploring Trace Results Tabbed Panel.

Path Analysis Requirements

There are four main requirements for Path Analysis to be functional. For more details, see shown in Figure 12-1:

•CiscoWorks Client running Path Analysis

•CiscoWorks Server

•Source of the path

•Destination of the path

Figure 12-1 Path Analysis Components

Path Analysis investigates and reports details on Layer 3 and Layer 2 paths between a source and destination (Leg 3 in Figure 12-1). For Path Analysis to be able to perform this analysis on Leg 3, Legs 1 and 2 must be functional.

For the path between the client and server (Leg 1) to be functional, there must be problem-free communication between server and client. (For example, problematic communication results when a firewall exists between the client and server.)

For the path between the server and the source (Leg 2) to be functional, the following requirements must be met:

•IP connectivity

•SNMP communication

•No routers configured to block source-routed IP packets. Make sure the router configuration does not contain the following statement:

no ip source-route

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Note By default, Cisco routers are configured to not block source-routed IP packets.

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For Layer 2 analysis to take place between the source and destination (Leg 3), the following conditions must be met:

•Both ends of a Layer 3 hop are managed Cisco devices known to the Topology Services application (device is a green icon on the topology view) or end-user stations known to the User Tracking application.

A question mark icon (unknown or inaccessible device) on either end of the Layer 3 hop indicates that the previously mentioned prerequisites are not met.

•All Cisco devices are running CDP.

•Path Analysis supports Layer 2 tracing on Ethernet, Fast Ethernet, Gigabit Ethernet, and LAN Emulation networks. LAN Emulation support includes tracing on the path inside an ATM cloud.

For this release, Path Analysis Layer 2 tracing does not support FDDI, Token Ring, and WAN interfaces or router bridge groups.

•Subnet to VLAN/ELAN mappings (automatically discovered or manually provided through the editor) are correct and complete. See the Mapping Subnet to VLAN/ELAN.

•Connectivity information for the subnet in question is known to Topology Services.

•The VLAN/ELAN information is known to Topology Services.

•The Layer 2 path does not involve router bridging (bridge groups).

•All Layer 2 devices are SNMP accessible.

•Install and configure DNS.

•For Voice over IP (VoIP) tracing, CDR logging must be enabled on all Media Convergence Servers.

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Note As a general rule, do not expect to see a Layer 2 path for every Layer 3 hop.

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Path Analysis uses the following sources of information:

•Network topology information

•Virtual LAN (VLAN)

•LAN Emulation (LANE)

•Direct SNMP

•Traceroute

•Ping

•User Tracking

Using Path Analysis Legend

The Path Analysis legend explains the use of icons and colors in network views. You can use the legend to identify devices in your network and their status. The legend includes all discoverable devices, including devices not in your network.

Color indicators described in the legend enable you to quickly determine the status of your network.

To use the Path Analysis Legend:

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Step 1 Select Help > Legend from the menu bar.

The Campus Manager Color and Icon Legend window opens. For details, see Table 12-1.

Step 2 Click Close to close the window.

Table 12-1 Color and Icon Legend 

Symbol	Description
Icons
	ATM Switch
	ATM-VLAN
	Ethernet VLAN
	Ethernet ATM-VLAN
	ATM-Domain
	Filter On
	FDDI Ring
	LE Client
	LE Config Server
	LE/Broadcast Server
	Link Port
	Network Topology View
	Switch Port
	Router
	Serial Bus
	Switch
	Switch Cloud
	Token Ring CRF
	Token Ring BRF
	Token Ring ATM-VLAN
	Unknown VLAN
	WAN Switch
	Embedded Router
	Embedded Switch
	Embedded SBC
	End Station
	Integrated Communications System
	Layer 2 and Layer 3 Switch Router
	Application Server
	Hub
	Switch Probe
	Voice Gateway
	Access Point
	Optical Services Router
	Cisco ONS Series Device
	Content Engine
	Content Server Switch
	DSL Switch
	Switch Stack
	Storage Switch
	Add Row
	Campus Manager Server Unknown
	Campus Manager Server Idle or Running
	ATM Switch Cloud
	Backup LECs
	Backup LE Bus
	Broadband Router
	Cisco CallManager
	Command Switch
	Device
	Navigate Down
	Fabric
	Fabric Cloud
	Link in Forwarding State
	Link in Blocking State
	Isolated VLAN
	Community VLAN
	Two-way Community VLAN
	Closed Folder
	Domain Folder
	Fabric Folder
	Open Folder
	Layer Map
	Route Switch Module (RSM) Switch
	Display All Rows
	Begin
	Stop Tree
	Open Saved Path Trace File
	Zoom to Fit
Icon Colors
	Major Fault (red)1
	OK (green)
	Minor Fault (yellow)
	Testing (magenta)
	Unknown (blue)
Links
	Active (black)
	Inactive (red)
	Not in network (red dashes)
	Unknown (blue)
Arrows
	Layer 2 Path
	Path between the devices is down
	Layer 3 Path

1 Device is not reachable using SNMP or the device is down.

Table 12-2 lists the special scenarios for Layer2/Layer3 Switch Router. For example, the switch is running Catalyst operating system, and the router is an MSFC or RSM router module:

Table 12-2 Icons for Discrepancies of Layer 2/Layer 3 Switch Router

Symbol	Description
	Router is reachable, but switch is unreachable using SNMP.
	Router is unreachable using SNMP, but switch is reachable.

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Setting Up Path Analysis

To set up Path Analysis, you must:

•Enable Cisco Discovery Protocol (CDP) on all devices that support it (required for Layer 2 tracing).

•Install and configure a Domain Name System (DNS) server on your network. Although Path Analysis does not require you to include the IP addresses for your network in your DNS database, we recommend that you do so.

–If Path Analysis cannot get the required IP address information for your network from Topology Services, it requests the information from your DNS server.

–If neither Topology Services nor your DNS server provides the required IP address information, traces might fail.

•Confirm that your DNS servers are valid and configured properly. Slow DNS response times affect Path Analysis performance.

•Enable Simple Network Management Protocol (SNMP) traffic on your network. Make sure your access control lists and Firewall rules do not block SNMP traffic generated by the CiscoWorks Server. Path Analysis requires SNMP access for tracing.

•Enter the correct SNMP read community strings on all devices.

•Enter the correct SNMP write community strings on all Catalyst 5000 devices. Otherwise, Path Analysis cannot determine shortcutting information. See Troubleshooting Suggestions.

•Start Topology Services and verify that all devices and interfaces are properly discovered. Properly discovered devices and interfaces appear in green in the Topology Services display.

If any devices appear in red, verify that they are reachable and have the correct community strings. Confirm that VLANs and Emulated LANs (ELANs) are properly discovered.

•Start User Tracking and run Discovery with ping sweeps to verify that all end-user hosts are discovered. Otherwise, Layer 2 traces fail for any end-user station that has not been discovered.

•Map subnet to VLAN/ELAN. For more details, see Mapping Subnet to VLAN/ELAN.

•Install Cisco CallManager with Call Detail Record (CDR) logging enabled. Otherwise, Voice over IP (VoIP) traces fail.

•Layer 3 tracing requires that you enable source routing on your network. Cisco routers have source routing enabled by default.

However, if you see the line no ip source-route in your Cisco IOS router or Route Switch Module (RSM) configuration file, you have disabled source routing.

Path Analysis Main Window

The Path Analysis Main Window consists of five areas:

1. Menu

2. Toolbar

3. End-point specification panel, including Start Trace and Stop Trace buttons

4. Trace Results tabbed panel, displaying trace results in a map, a textual trace log, or a table and errors encountered during the trace.

5. Status bar

For more information, see Figure 12-2.

Figure 12-2 Path Analysis Main Window

1	Menu	7	Layer 3 path traced using trace route
2	Toolbar	8	Direction of the path in Layer 3
3	End-point specification panel	9	Layer 3 path traced using SNMP
4	Layer 2 path traced using SNMP	10	Trace map
5	Direction of the path in Layer 2	11	Tab panel
6	Status bar

This section contains the following topics:

•Path Analysis Commands

•Understanding Path Analysis Toolbar

•Understanding End-Point Specification Panel

•Exploring Trace Results Tabbed Panel

•Understanding Status Bar

Path Analysis Commands

You can perform most Path Analysis functions by selecting commands from the File, Edit, and Action menus. Commonly used menu functions are also available in the toolbar.

Several commands have corresponding keyboard shortcuts, toolbar buttons, or both. For more details, see Table 12-3.

Table 12-3 Path Analysis Command Reference 

Menu	Command	Keyboard Shortcut	Toolbar Button	Description
File	Open Trace	Ctrl+o		Retrieves and displays a path trace saved to a file. See Displaying Saved Traces.
	Save Trace As	Ctrl+s		Saves current path trace to a file for later retrieval or display. See Saving a Trace.
	Export Trace Tab Text	Ctrl+e	None	Exports trace results to an ASCII text file.
	Print	Ctrl+p		•Prints current contents of Trace Results tabbed panel, as: –A map –A table –Text This depends the tab you select.
	Exit	None	None	Closes Path Analysis application.
Edit	Copy	None	None	Copies current selection from any of these: •From field •To field •Trace display •Table display To the system clipboard.
	Paste	None	None	Pastes information from clipboard.
	Subnet Mapping	Ctrl+m	None	Displays VLAN/ELAN Subnet Mapping table. See Editing the VLAN/ELAN Mapping Table.
	Options	None	None	Displays user configurable options for Path Analysis.
Action	Start Trace	Ctrl+t		Triggers a path trace between specified end-points. See Beginning a New Trace.
	Stop Trace	None	None	Aborts a path trace between specified end-points. See Beginning a New Trace.
	Reverse Trace Direction	Ctrl+r	None	Transposes the To and From values. See Reversing Traces.
	Discover All	Ctrl+d	None	Starts device discovery, ping sweeps, and User Tracking discovery.
	Highlight Path in Network View	Ctrl+l		Highlights Layer 2 path in Topology Services network map, if a Topology Services session is already active in the same Web browser.
Help	Using Path Analysis	Ctrl+h	None	Opens Path Analysis Online help.
	About Path Analysis	Ctrl+b	None	Displays Path Analysis copyright information.

The behavior of the Edit > Copy command varies depending on the active selection. If you select a range of cells in Table display, the column headings append to the selection that automatically separates using tab, when you paste it.

User-Configurable Options

To configure some settings for the Path Analysis client software.

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Step 1 Select Edit > Options.

The Path Analysis Options window opens.

Table 12-4 lists fields in this window.

Table 12-4 Path Analysis Options Window 

Field	Notes
Timeout Path trace after (minutes)	Enter a whole number greater than 0. The default is 4.
Precedence for data trace (For UNIX servers only)	Enter a whole number. In most cases, the appropriate number is 0. However, if you are tracing VoIP traffic through IP addresses instead of telephone numbers, set this value to 5.
Precedence for voice trace (For Unix servers only)	Enter a whole number. Typically, the appropriate number is 0.
Call start time granularity (minutes)	Enter a whole number (preferably under 15 minutes). A larger time range returns more CDRs and is therefore more likely to exceed the 100-record limit.

Step 2 Click OK to save your changes.

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Understanding Path Analysis Toolbar

The Path Analysis toolbar contains five buttons:

Table 12-5 Five Menu Commands in Toolbar 

Button	Description	Usage Notes
	Opens a saved trace.	See Displaying Saved Traces.
	Saves a trace.	See Saving Traces.
	Prints trace results.	None.
	Starts the trace.	See Starting and Stopping Traces.
	Highlights Layer 2 path in Topology Services network map.	See Viewing the Path in Topology Services.

Understanding End-Point Specification Panel

You can use the fields, buttons, and tabs in the end-point specification panel to choose the source and destination of your path trace, and to start or stop a trace. See Table 12-6 for details.

Table 12-6 Field Description of End-Point Specification Panel 

Field/Button/Tab	Description	Usage Notes
From	Provides starting point for path trace.	Enter the IP address or device name of a Cisco device or end-user host for initial trace end-point. See Specifying Valid Points.
To	Provides stopping point for path trace.	Enter the IP address or device name of a Cisco device or end-user host for final trace end-point. See Specifying Valid Points.
Data Trace	Specifies standard network traffic trace between IP addresses or named devices.	In the Trace Type area, click Data Trace button.
Voice Trace	Specifies Voice over IP (VoIP) traffic trace between telephone numbers.	In the Trace Type area, click Voice Trace button.
Start Trace	Begins a path trace and refreshes the display.	•Button disabled while a trace is in progress. •Button unavailable if you click Voice Trace. You can also start a trace from the Action menu or the toolbar. See Starting and Stopping Traces.
Stop Trace	Discontinues a path trace in progress.	•Button enabled only while a trace is in progress. •Button unavailable if you click Voice Trace. You can also stop a trace from the Action menu or the toolbar. See Starting and Stopping Traces.
Find Call	Opens the Voice Trace Query window.	Button available only if you click Voice Trace.

You can select Action > Reverse Trace Direction to exchange the content of the From and To fields, to verify the reverse connectivity between two end-points.

Exploring Trace Results Tabbed Panel

The Trace Results tabbed panel allows you to see the current path as a view, a trace log, or a table. The display refreshes on screen as the trace progresses.

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Note The Table display updates only when the trace is complete.

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Table 12-7 Tab Description of Trace Results Tabbed Panel 

Button/Tab	Description	Usage Notes
Help button	Displays Online help.	None.
Map tab	Displays Path Trace map.	See Understanding Map Display.
Trace tab	Displays messages received from the Path Analysis service module in ANI.	See Understanding Trace Display.
Table tab	Displays Path Trace values table.	See Understanding Table Display.

•If you select the Map tab, the Trace Results Tabbed Panel displays managed devices and Layer 2 and Layer 3 connections between the specified end-points.

•If you select the Trace tab, the Trace Results tabbed panel displays a trace log of messages received while discovering the path. The results are similar in many respects to traceroute results.

•If you select the Table tab, the Trace Results tabbed panel displays one row for each managed device discovered in the trace. Each row is subdivided in columns that specify device parameters such as MAC address and subnet mask.

You can switch views without any loss of data. There are advantages and disadvantages to each of the three views. This section contsains the following topics:

•Trace Results Tab View Advantages and Disadvantages

•Understanding Map Display

•Understanding Tooltips in Map Display

•Understanding Trace Display

•Understanding Table Display

Trace Results Tab View Advantages and Disadvantages

Each of the three views in the Trace Results tabbed panel has advantages and disadvantages.

Table 12-8 Advantages and Disadvantages of Trace Tab Views

View	Advantages	Disadvantages
Map	Displays any complex path structure, including branches and routing loops, if Layer 2 trace succeeds. The display is built dynamically when a trace in progress.	Limited display of interface properties. Data presented in the Map display cannot be copied to the clipboard.
Trace	Provides a terse summary that builds dynamically with the trace in progress. Use the Copy command for ASCII import to a text editor.	Summary stops refreshing at first branch or routing loop.
Table	Displays interface properties in detail. Use the Copy command for tab-delimited import to a spreadsheet.	No data is displayed until the trace concludes. Display is linear and stops refreshing at the first branch or routing loop.

You can switch views without any loss of data.

Understanding Map Display

The Map tab displays managed devices and Layer 2 and Layer 3 connections. The start point is displayed at the top of the map and the stop point is displayed at the bottom.

The Map tab also displays a router-to-router Layer 3 Path and a Layer 2 Path. For more details, see the following topics:

•Layer 3 Path

•Layer 2 Path

Layer 3 Path

The Layer 3 path connects the end-stations and intervening routers that establish the hops taken at the IP layer.

Layer 2 Path

The Layer 2 path supplements the Layer 3 path, because it shows the connections among intermediate switches that carry the traffic flow between routers.

Shortcut connections appear as extra arcs on the right side of the map, and represent Layer 2 path connections between switch ports that bypass intervening routers and switches once their initial routing decisions are made.

Tips

•By default, the map displays the appropriate switch icon for each Layer 2 device discovered, a router icon for each Layer 3 device discovered, and an end-user station icon for each discovered end-user station. The map uses the same icons used in the Topology Services network map.

•Right-click an icon in Map view to launch Telnet, CiscoView, or Visual Switch Manager.

•Right-click a device icon in map view and select Highlight Device to highlight the device in Topology Services Layer 2 network map. (A Topology Services session must be already active in the same Web browser)

•Right-click a Layer 2 link icon in map view and select Highlight Link to highlight the Layer 2 link in Topology Services network map. (A Topology Services session must be already active in the same Web browser)

Understanding Tooltips in Map Display

In addition to the static, self-contained tooltips that appear over buttons and tabs in the Path Analysis map display, other tooltips might contain variable information:

•Node Icon Tooltips

•Layer 3 Link Tooltips

•Layer 2 Link Tooltips

•Layer 2 Shortcut Tooltips

Node Icon Tooltips

Node icon tooltips in the map display can contain the following categories of information.

Table 12-9 Node Icon Tooltip Label Description 

Tooltip Label	Description
IP Address	Primary numbered interface known to DNS.
Alias	Primary name associated with the IP address, if known.
Device Class	Hardware description, if known.
Device Type	SNMP hardware model number, if known.
Uptime	Time elapsed since the device was reset, in DD:HH:MM:SS format, if known.

Layer 3 Link Tooltips

Layer 3 link tooltips in the map display can contain the following categories of information.

Table 12-10 Layer 3 Link Tooltip Label Description

Tooltip Label	Description
From	Numeric IP address of the transmitting interface.
To	Numeric IP address of the receiving interface.
Route Protocol	Simple Network Management Protocol (SNMP) route type, such as local, ciscoIgrp, Routing Information Protocol (RIP), or Open Shortest Path First (OSPF), if known.
Route Age	Elapsed time since the cache was reset, if known. Shows zero if no counter is set.
Delay	Milliseconds for three successive packet transmission attempts, if known.
(Best Guess)	Appears only when link information is conflicting or incomplete.

Layer 2 Link Tooltips

Layer 2 link tooltips in the map display can contain the following categories of information.

Table 12-11 Layer 2 Link Tooltip Label Description 

Tooltip Label	Description
Link Type	Link type from Management Information Base (MIB), such as ATM, Ethernet1000M, or AFLANE8023.
From	Numeric IP address of the transmitting interface.
To	Numeric IP address of the receiving interface.
VPI	8-bit Virtual Path Identifier (VPI) in an ATM cell header.
VCI	16-bit Virtual Channel Identifier (VCI) in an ATM cell header.

Layer 2 Shortcut Tooltips

Layer 2 shortcut tooltips in the map display can contain the following categories of information.

Table 12-12 Layer 2 Shortcut Tooltip Label Description 

Tooltip Label	Description
Route Engine	Name of the router that determined that a shortcut was possible. Typically this router is in the center of the shortcut arc.
Switch Engine	Name of the switch highlighted in the map display.

Understanding Trace Display

The Trace tab displays messages received from the Campus Manager Server's Path Analysis service module during Path Discovery, as follows.

Table 12-13 Interpreting Trace Tab Messages

Field	Description
TimeStamp	Date and time of the trace.
Learned By	One of the four discovery methods described in Path Analysis Discovery Methods.

The Trace display is similar to traceroute, with two enhancements. Trace displays show both incoming and outgoing interfaces, and every Layer 2 hop.

Other Trace display output is similar to that in a standard traceroute log.

Path Analysis Discovery Methods

Path Analysis relies on four Discovery methods. The name of one or more of these methods appears in the Learned By field in the Trace display.

Table 12-14 Discovery Methods in Path Analysis

Learned By	Source	Confidence	Remarks
Direct SNMP	Simple Network Management Protocol (SNMP) access on device	Highest	None.
NMS Server	Most recent data collection or device Discovery	High	Network reconfiguration obsoletes previously discovered data. Select Action > Discover All if network configuration has changed since last Discovery.
Traceroute	Traceroute program	High	None.
Best Guess	Conflicting or incomplete information sources	Low to Moderate	None.

Understanding Table Display

The Table tab displays one row of device data for each managed device that forwards packets anywhere between the specified start and stop points. There are 20 table tab columns. For more information, see Table 12-15.

Table 12-15 Table Tab Column Description 

Column	Description
Direction	Direction packet travels through the device: in or out.
Device Address	One IP address that identifies the device.
Device Alias	Device name, NT domain name, or other name of the device.
Device Class	One of the following: •Router •ATM Switch •LAN Switch •Hub •End-Station
Device Type	Type of chassis associated with the device.
Device Uptime	Elapsed time since last power-on device reset.
Interface Name	ifName—See RFC 1213, Management Information Base for network management of TCP/IP-based internets: MIB-II.
Interface Address	IP address of interface, if available.
Interface Mask/Prefix Length	IP netmask for interface with IP address/mask.
ifIndex	Interface identifier—See RFC 1213.
MAC Address	Standard data link layer address for the network adapter.
Interface Type	Network specification associated with the adapter.
Interface Speed	In kilobits, megabits, or gigabits per second.
MTU	Maximum Transmission Unit—maximum packet size, in bytes, that the interface supports.
VTP Domain	Name of the VLAN trunking protocol domain for the VLAN associated with this interface.
VLAN Name	Name of the VLAN associated with this interface.
ATM Fabric	Name of the ATM fabric associated with the ELAN for this interface.
ELAN Name	Name of the ELAN associated with this interface.
VPI	Virtual Path Identifier (VPI) for the Cisco IOS Inverse Multiplexing of the ATM fabric
VCI	Virtual Channel Identifier (VCI) for the Cisco IOS Inverse Multiplexing of the ATM fabric

Values displayed in the columns represent device state information that Path Analysis found during the trace.

You can drag columns to temporarily rearrange their display order. This operation is useful before printing the table.

Understanding Status Bar

The status bar at the bottom of the main Path Analysis window displays informational, diagnostic, and warning messages regarding Layer 3 traces. See Monitoring Trace in Progress.

Mapping Subnet to VLAN/ELAN

The Path Analysis application uses information from User Tracking to determine the mapping of subnets to Virtual LANs (VLANs) and Emulated LANs (ELANs).

In some cases, the information may be incomplete. In these cases, you can edit a VLAN/ELAN mapping table, to supplement the User Tracking information. See Editing VLAN/ELAN Subnet Mapping Table.

Use the mapping editor to supplement the Auto-Discovery mappings, and also consider that:

•Subnet-to-VLAN mappings might not be discovered in a subnet that contains no end-user hosts.

•User Tracking does not discover subnets that are only on ISL trunks and Cisco Discovery Protocol (CDP).

This section contains the following topics:

•Understanding VLAN/ELAN Subnet Mapping Table

•Editing VLAN/ELAN Subnet Mapping Table

•Verifying Subnet Mapping Table Entries

•Using Subnet Mapping Table for Layer 3 Traces

•Using Subnet Mapping Table for Layer 2 Traces

Understanding VLAN/ELAN Subnet Mapping Table

The VLAN/ELAN Subnet Mapping Table displays Virtual LAN (VLAN), Emulated LAN (ELAN), and associated subnet mappings. This information can be useful when performing Layer 3 traces and is required to perform Layer 2 traces.

You should view the VLAN/ELAN Subnet Mapping Table during the initial setup of Path Analysis and whenever you change subnet mapping.

While viewing the table, you can add or delete entries in the table, or discover a fresh set of information.

On a typical network, information displayed in the table is discovered automatically by the Path Analysis application. You may need to insert additional entries in case the information is not discovered automatically.

The first three columns in the VLAN/ELAN Subnet Mapping Table contain text that cannot be edited. The column headings are Entry Type, VTP Domain/ATM Fabric, and VLAN/ELAN.

All of the other columns in the table appear under the Subnet column heading. You can edit the text in any Subnet column. See Editing VLAN/ELAN Subnet Mapping Table for instructions.

You can also sort the values in any of the columns in the Subnet mapping table in order to locate the entry you want to modify.

One of the following font styles is used to render information in a cell. The use of a particular font conveys information about the source and validity of a mapping:

•Black, plain type indicates an automatically discovered mapping that is known to the system.

•Blue, italic type indicates a manually provided mapping that is unknown to the system.

•Red, bold type indicates invalid information (for example, bad syntax).

For an explanation of the Clear, Discover, Apply, and Cancel buttons, see Editing VLAN/ELAN Subnet Mapping Table.

Editing VLAN/ELAN Subnet Mapping Table

Layer 2 analysis fails on any subnet for which the VLAN/ELAN Subnet Mapping Table is incomplete or inaccurate. Therefore, you must maintain accurate and complete VLAN and ELAN mapping. You can use Path Analysis to:

•View previously supplied manual mappings

•View only auto-discovered mappings

•View all known subnet mappings

•Erase previously supplied manual mappings

•Modify the subnet mapping table

•Clear local entries only

•Clear all entries

•Verify the need for manual entry

Use the buttons centered near the bottom of the VLAN/ELAN Subnet Mapping Table window to help you maintain accurate and complete mappings. For more details, see Table 12-16.

Table 12-16 Description of Buttons in VLAN/ELAN Subnet Mapping Table 

Button	Function
Clear	Erases all subnet entries from the displayed table.
Discover	Shows automatically discovered information in the displayed table.
Apply	Commits changes in the displayed table (caused by Discovery or manual entry) to the server. All subsequent traces use data applied to the server to supplement discovered data.
Cancel	Closes the window without applying changes.

Path Analysis uses only the single copy of the subnet to VLAN mapping table that is saved on the server. You can use the Apply button to save changes to the mapping table on the server.

The results of automatic Discovery might vary over time, even if the structure of your network is unchanged.

•If you obtain a complete set of information using Discovery, you can apply that information to the server, in case subsequent discoveries are incomplete.

•If you remove a VLAN/ELAN from your network, you must remove the corresponding information from the mapping table.

•If entries are displayed in the table and you click Discover, any new information appends to the existing display. No information is deleted.

There is no visual difference in the presentation of pre-existing and new information in the table. For information about visual cues to help you understand the table display at a glance, see Understanding the VLAN/ELAN Mapping Table.

This section contains the following topics:

•Displaying Previously Supplied Manual Mappings

•Displaying Auto-Discovered Mappings

•Displaying All Known Subnet Mappings

•Erasing Previously Supplied Manual Mappings

•Modifying Subnet Mapping Table

•Clearing Local Entries

•Clearing All Entries

•Verifying Need for Manual Entry

Displaying Previously Supplied Manual Mappings

You can view the previously supplied manual mappings of subnets to VLANs/ELANs, without viewing automatically discovered mappings. To do this select Edit > Subnet Mapping to open the Subnet Mapping window.

Displaying Auto-Discovered Mappings

You can view auto-discovered subnet-to-VLAN and ELAN mappings without viewing manual mapping entries. To do this:

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Step 1 Select Edit > Subnet Mapping.

Step 2 Click Clear.

Clears all manual entries from the table and retains only the auto-discovered mappings.

Step 3 Click Discover.

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Displaying All Known Subnet Mappings

You can view all subnet-to-VLAN/ELAN mapping entries at once, including those that are manually supplied and those that Path Analysis discovered automatically. To do this:

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Step 1 Select Edit > Subnet Mapping.

Step 2 Click Discover.

All known subnet-to-VLAN/ELAN mappings appear in the table.

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Erasing Previously Supplied Manual Mappings

To erase all subnet-to-VLAN and ELAN mapping entries that were entered manually. To do this:

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Step 1 Select Edit > Subnet Mapping.

Step 2 Click Clear.

Step 3 Click Apply.

Erases all manual entries for subnet mapping from the database in the server.

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Modifying Subnet Mapping Table

You can modify the entries in the subnet-to-VLAN and ELAN mapping table. To do this:

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Step 1 Select Edit > Subnet Mapping.

Step 2 Click Discover.

Step 3 Review the table for accuracy.

If any previously supplied information in a cell is no longer valid, click to highlight text in that cell, then enter the correct information.

Accurate information in the table is important for Level 3 traces, and is essential for Level 2 traces.

Step 4 Verify your subnet mapping table entries.

Step 5 Click the Apply button.

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If you modify the subnet mapping table, do not edit the auto-discovered (black) text. The next Auto-Discovery overwrites any changes you might make.

Clearing Local Entries

You can clear entries in the subnet-to-VLAN/ELAN mapping table without deleting any information from the server. To do this:

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Step 1 Select Edit > Subnet Mapping.

Step 2 Click Clear.

Entries from your local subnet mapping display are cleared. However, these entries remain on the server.

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Clearing All Entries

To clear the subnet-to-VLAN/ELAN mapping table entries stored both locally and on the server.

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Step 1 Select Edit > Subnet Mapping.

Step 2 Click Clear.

Step 3 Click Apply.

Entries from your local subnet mapping display are cleared. However, these entries remain on the server.

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Verifying Need for Manual Entry

To verify whether you must enter subnet mapping information manually.

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Step 1 Select Edit > Subnet Mapping.

Step 2 Click Clear.

Step 3 Click Discover to see the automatically discovered mapping of subnets to VLANs or ELANs, as well as subnets that do not map to any VLAN or ELAN.

Where information is incomplete, enter complete information manually.

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Verifying Subnet Mapping Table Entries

Use the following guidelines to verify VLAN/ELAN subnet mappings according to their description in the Entry Type column. Specify this information only if the automatic Discovery process has not already supplied it.

Table 12-17 Subnet Mapping Table Entry Description 

Entry Type	Guidelines
VLAN	Specify the subnets that correspond to the VLAN. Enter this information in the first blank Subnet column in that row. If there is no corresponding subnet, leave all of the Subnet columns for that row blank.
ELAN	Specify the subnets that correspond to the ELAN. Enter this information in the first blank Subnet column in that row. If there is no corresponding subnet, leave all of the Subnet columns for that row blank.
Subnet	Specify the subnets that do not correspond to a VLAN or ELAN. Enter this information in the first blank Subnet column for that row. Any row whose entry type is Subnet is equivalent to any other such row. All Subnet rows can be used interchangeably.

Using Subnet Mapping Table for Layer 3 Traces

Successful Layer 3 tracing requires that all subnets within the managed domain be listed in one of the Subnet Mapping Table rows.

Use information in the Subnet Mapping Table to identify non-Cisco or non-Cisco Discovery Protocol (CDP) devices. These are devices that are not discovered or displayed in Topology Services following your use of its View > Display View command.

Layer 3 traces would generally access these devices through SNMP unless they reside on a known, managed subnet within the organization. Layer 3 path traces make this determination by referencing these devices to the VLAN/ELAN Mapping Table.

If a subnet has no entry in the table, there will be no SNMP information in the table view or outgoing interface information for the non-Cisco or non-CDP devices on that subnet. However, Layer 3 path traces will function properly in all other respects, however.

Enter the subnet IP address to provide subnet information manually where a subnet is not associated with a VLAN or ELAN and is therefore not included in the Subnet Mapping Table.

The Entry Type column shows three types of entries:

•VLAN

•ELAN

•Subnet

If the Entry Type column shows VLAN or ELAN, subnets for corresponding VLANs or ELANs are listed in the Subnet column(s) for that row.

If the Entry Type column shows Subnet, the stand-alone subnet (one that does not map to a VLAN or ELAN) appears in the first Subnet column for that row. Do not add entries in the Subnet column for stand-alone subnets.

You can add subnet mappings manually for VLANs and ELANs with no Subnet column entries. You can also enter additional subnet mappings for any of the VLANs or ELANs that appear.

Using Subnet Mapping Table for Layer 2 Traces

You can specify three types of entries in the Subnet Mapping Table:

•Virtual LAN (VLAN)

•Emulated LAN (ELAN)

•Subnet

For each VLAN or ELAN entry in the table, you can specify the subnets that reside on that VLAN/ELAN. If this information is not provided manually and cannot be discovered automatically, Layer 2 tracing cannot occur on that subnet.

Therefore, you should check the automatically discovered values following an installation, and enter any needed information. If information is missing from the VLAN/ELAN mapping table, no Layer 2 traces are performed on the subnets with missing mapping information.

The following conditions are acceptable mappings:

•A VLAN/ELAN is not mapped to a subnet if that is the actual case in the network. This can occur, for example, when a VLAN or ELAN is used for non-IP traffic.

•A VLAN/ELAN is mapped to more than one IP subnet. This is not a common configuration, but it does occur occasionally in some networks.

•A single subnet is mapped to multiple VLAN/ELAN entries. This occurs when you have multiple VLANs and ELANs bound together to form a larger LAN that corresponds to a subnet.

Understanding Traces

You can trace the connectivity between two specified devices on your network. This includes physical and logical paths taken by packets flowing between those points.

For performing a trace, you must:

•Begin a new trace. For more details, see Beginning New Trace

•Monitor the progress of the trace. For more details, see Monitoring Trace in Progress

After completing a trace, you can perform:

•Reversing Traces

•Saving Traces

•Displaying Saved Traces

Beginning New Trace

To start a new trace, you must perform the following tasks:

•Discovering Networks

•Specifying Valid Points

•Starting and Stopping Traces

Discovering Networks

You can perform Discovery when:

•Network topology has changed.

•Network devices or end-user devices have been moved, added, or removed.

•IP address assignments have changed.

•The operational or administrative status of devices or interfaces has changed since the last topology or User Tracking discovery cycle.

By default, the global Discovery cycle in the Campus Manager Server runs every 4 hours. The user and host Discovery cycle occurs on a user-configurable, fixed cycle, twice daily. Discovery might take several minutes or longer to complete, depending on network size.

To begin Discovery, select Action > Discover All to run device discovery, ping sweeps, and User Tracking Acquisition.

If a full discovery is not necessary, you can either:

•Select Edit > Perform Data Collection in the Topology Services Network Topology window to run a partial device Discovery.

Or

•Run User Tracking Discovery (with or without ping sweeps) from the User Tracking application.

Specifying Valid Points

Before you select source and destination end-points for a trace, see Understanding Valid Points.

The Path Analysis Main Window features two end-point selector fields, labeled From and To. In these fields you can enter a device name or IP address, or paste a selected node name or IP address copied from the Topology Services network map or User Tracking.

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Step 1 Enter the trace source end-point in the From field.

Step 2 Enter the trace destination end-point in the To field.

Step 3 Start the trace.

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You can specify either a device name or an IP address for an end-point. However, if a single device has multiple interfaces with IP addresses, each interface could trace differently.

Furthermore, if you specify as one of your end-points the name for a device with multiple interfaces, the IP address selected varies according to when you start the trace. For precision in such instances, use IP addresses instead of ambiguous device names.

Understanding Valid Points

You can select source and destination end-points for a trace by:

•Entering a device name or IP address

•Copying and pasting node names or IP addresses selected from Topology Services

•Copying and pasting node names or IP addresses highlighted in User Tracking

A trace source end-point must be inside the managed organization for accurate Path Analysis results. It can be either:

•A device known to the Campus Manager Server or User Tracking, such as a LAN switch, an ATM switch, a router, or a fast hub that supports Cisco Discovery Protocol (CDP)

Or

•An end-user host discovered by User Tracking

For Layer 2 tracing, a trace source end-point must be a Cisco device. Layer 3 tracing supports any trace source end-point inside the managed organization.

A trace source end-point must be reachable from the CiscoWorks Server. If it is not reachable, an alert message appears. See Understanding Alert Messages.

A trace destination end-point can be any IP address or device name on the Internet, including addresses outside the managed organization.

However, Firewalls and devices along the path that do not support source-routed IP packets can prevent Path Analysis from completing a trace to its intended destination. Layer 2 tracing, where possible, occurs only inside the managed organization.

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Note Layer 3 tracing does not support PCs or workstations with more than one network adapter. In this release, Path Analysis does not support devices using the AppleTalk or IPX protocol.

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You can specify a source end-point outside of the managed domain. However, since trace results from this usage might not be completely accurate, we do not recommend this.

Starting and Stopping Traces

After you specify start and stop points in your network, start the trace. Before starting the trace:

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Step 1 Perform network and end-user host Discovery, if needed.

Step 2 Specify valid start and stop points in the Path Analysis Main Window.

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From the Path Analysis Main Window:

•To start a trace, click Start Trace, or select Action > Start Trace.

•To stop a trace, click Stop Trace, or press Enter.

A path trace might take several minutes to complete.

Monitoring Trace in Progress

Path Analysis provides many visual cues to help you conceptualize the status of your network. These cues include status bar messages while the trace is under way, and color icons and lines of various kinds as Path Analysis draws onscreen in Map View.

In Map View and Trace View, Path Analysis displays the path as it is analyzed. The Path Analysis process takes from about one minute to several minutes, depending on the complexity of the network and the response times of the nodes. This section contains the following topics:

•Understanding Status Bar Messages

•Understanding Alert Messages

•Layer 2 and Layer 3 Path Trace Errors

•Understanding Lines in Map View

•Understanding Icons in Map View

Understanding Status Bar Messages

All status bar messages see the Layer 3 path trace. For more details, see Table 12-18.

Table 12-18 Status Bar Messages 

Message	Definition	Severity	Possible Solution
`From" Field Contains Bad Source Endpoint	Invalid string entered for path trace source.	Low	Confirm that the From field entry is a valid IP address or device name.
'To' Field Contains Bad Destination Endpoint	Invalid string entered for path trace destination.	Low	Confirm that the To field destination entry is a valid IP address or device name.
Source and Destination Endpoints are on same device	Not possible to trace path between two IP addresses on one device.	Low	Make sure that the To and From entries are not for the same device.
Trace Running	Trace has not yet completed.	-	-
Trace Aborted	Error or anomalous situation prevented successful path trace.	Variable	-
Trace Timed Out	Trace attempt exceeded timeout value (default is 4 minutes). Path traces can take up to several minutes to complete.	Variable	Select Edit > Options and increase default trace timeout value.
Trace Stopped	User stopped trace.	-	-
Trace Completed	Trace completed successfully.	-	-

Understanding Alert Messages

All alert messages see the Layer 3 path trace.

Table 12-19 Alert Message Description 

Message	Definition	Severity	Possible Solutions
Could not complete trace	One or more Layer 3 hops determined, but trace did not reach destination. Typically results from Firewall rules, access lists, or blocked IP source-routed packets.	Variable	1. Choose a destination on the same side of the firewall as the source. 2. Verify access lists along the path and correct any problems. 3. Confirm that no routers along the path block source-routed IP packets.
Could not determine first hop	No known hops. Information to determine first hop is incomplete or inconsistent.	High	1. Confirm that source is in managed domain and SNMP-accessible. 2. Verify community strings. 3. Confirm that end-user stations are not multi-homed (containing multiple NICs). Path Analysis does not support this configuration.
Could not reach source	No IP connectivity between CiscoWorks Server and source.	High	Run a path trace between the CiscoWorks Server and the source to analyze IP connectivity. Ping the device to determine if it is reachable.

Layer 2 and Layer 3 Path Trace Errors

Path Analysis displays error messages on unsuccessful Path Analysis for Layer 2 and Layer 3. See the following topics to interpret these messages:

•Layer 2 Information Message

•Layer 2 Errors

•Layer 2 Warnings

•Layer 3 Warnings

•Layer 3 Errors

Layer 2 Information Message

Table 12-20 Layer 2 Information Message

Message	Cause
No short cut flow determined.	Short cut flow may not be functional.

Layer 2 Errors

Table 12-21 Layer 2 Error Message

Message	Cause
Cannot get the Layer 2 trace between the devices.	•Subnet-to-VLAN mapping table for the devices maybe incomplete. •Switching path may not be available between the devices. •Intermediate device(s) are not in the network, cannot be reached through SNMP, or has not been discovered by the Campus Manager Server.

Layer 2 Warnings

Table 12-22 Layer 2 Warnings Message

Message	Cause
Cannot get the Layer 2 trace between the devices.	•Either one of the devices is not fully managed. or •Both devices may be managed, but Path Analysis may not have complete information.

Layer 3 Warnings

Table 12-23 Layer 3 Warnings Message

Message	Cause
Not properly managed by Cisco Works Server.	The device is not in the network, cannot be reached through SNMP, or has not been learnt by the Campus Manager Server

Layer 3 Errors

Table 12-24 Layer 3 Error Messages 

Message	Cause
Cannot get the first hop information from the source device.	Failure caused by the timeout of LSR traceroute and IP record route requests.
Cannot reach the device from Cisco Works server.	The device cannot be reached from the CiscoWorks Server
One or more Layer 3 hops from the source were determined, but the trace could not reach the destination.	Failures caused by routing problems, firewalls, access lists, or blocked source-routed IP packets.
Hop between device X and device Y: Routing loop observed between X and Y.	Improper configurations in the devices.

Understanding Lines in Map View

Types of lines in Map View:

•Solid lines in Map View represent the combined results of Network Management System (NMS) server queries, direct Simple Network Management Protocol (SNMP) activity, and Traceroute. Therefore, information represented by solid line arcs is usually accurate.

•Dashed lines in Map View represent a best guess, based upon conflicting or incomplete records. Therefore, a dashed-line arc might or might not be accurate and should be viewed with a lower degree of confidence.

•Red arrows in Map View represent routing loops.

•Black lines in Map view represent Layer 3 traces.

•Blue lines in Map view represent Layer 2 traces.

Understanding Icons in Map View

Icons in the Map view represent discovered Layer 3 devices known to Topology Services. Additional icons can represent Layer 2 devices known to the Network Management System (NMS), or end-user stations known to User Tracking.

The lines that connect these icons in the Map view provide additional information about the path trace.

Position your mouse or pointer above an icon in the Map view to view tooltips that provide device information.

Table 12-25 Icons in Map View 

Icon	Type of Device
	Unmanaged or inaccessible device that is unknown to Topology Services, or a user or host that is unknown to User Tracking. Path Analysis makes no effort to run a Layer 2 trace to or from the unknown device.
	Cisco CallManager installation.
	IP phone.
	End-user station.

Reversing Traces

To check the reverse direction connectivity between two end-points.

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Step 1 Select Action > Reverse Trace Direction.

Contents of the end-point selector boxes are switched.

Step 2 Click Start Trace in the Main Window, or select Action > Start Trace.

The reverse trace starts and Path Analysis displays the reverse path as it is analyzed.

The Path Analysis process takes from about one minute to several minutes, depending on the complexity of the network and the response times of the nodes.

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Saving Traces

You can save trace information and view it later. All information displayed below the Map, Table, and Trace tabs is saved. See Displaying Saved Traces.

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Step 1 Select File > Save Trace As, or click Save icon in the toolbar.

The Path Save dialog box appears.

Step 2 Enter a unique name for the saved data, or use the default name, in the label field.

Step 3 Click OK.

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Paths are dynamic and vary according to current network status. Therefore, the path between any two end-points might change over time.

Displaying Saved Traces

To display a saved trace.

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Step 1 Select File > Open Trace.

Path trace files are displayed in the Load Path Trace dialog box.

Step 2 Enter the name of the saved path trace file you want to view.

You can enter known filenames in the label field. Otherwise, select the name from the list of files displayed in the drop-down list box.

Step 3 Click OK.

The selected path trace is displayed in the active tab.

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Displaying User Archived Traces

You can view the traces archived using Path Analysis.

To interpret the fields in the View User Archived Traces dialog box, see Table 12-26.

Table 12-26 User Archived Traces Field Description 

Field	Description
Trace No.	Unique ID generated by Path Analysis for every trace archived
Source	IP address of the source
Destination	IP address of the Destination
Archived Time	Time at which trace was archived

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Step 1 Select Edit > View User Archived Traces from the menu bar in the Path Analysis Main Window.

The View User Archived Traces dialog box appears.

•To view a user archived trace, select an entry and click View.

•To delete the user archived trace from the archive, select an entry and click Delete.

Step 2 Click Refresh to see the updated list of archived traces.

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Tracing Voice Over IP Traffic

You can determine the data paths and troubleshoot the signaling paths that Voice over IP (VoIP) traffic uses on your network.

Additionally, you can trace the flow of packets for three types of VoIP telephone calls on your data network. For more details, see Table 12-27.

This section contains the following topics:

•Understanding Voice Trace Window

•Performing Voice Over IP Trace

•Enabling CDR Logging in Cisco CallManager

•Understanding CDR Query Status Log

•Understanding Called Number Matching

•Understanding Called Time Matching

•Understanding Calling Number Matching

Table 12-27 provides a detailed description of VoIP telephone call types and the trace methods.

Table 12-27 VoIP Telephone Call Type Description 

Type of Call	Description	Trace Method
Completed call	Telephone call that has occurred and completed. Call Detail Records (CDRs) exist only for completed calls.	Trace as voice data, using telephone number of the called (destination end-point) telephone.
Call in progress	Telephone call that has begun, but has not concluded.	•Get IP addresses in User Tracking for voice-enabled devices and gateways in your network. •Trace packets as standard data, using end-point IP addresses. Do not use telephone numbers. (No CDR exists for a call in progress.)
Potential call	Telephone call that has not occurred, but might occur in the future.	•Get IP addresses in User Tracking for voice-enabled devices and gateways in your network. •Trace packets as standard data, using end-point IP addresses. Do not use telephone numbers. (No CDR exists for a potential call.)

Understanding Voice Trace Window

You can refine your Voice over IP (VoIP) path trace queries in the Voice Trace Query window. To understand the window, see Table 12-28.

Table 12-28 Voice Trace Window Description 

Field/Button/Check Box	Description
Called Number	Enter all (or the trailing part) of the destination end-point telephone number. Only numerals are valid in this field; all other characters are ignored. Enter complete telephone numbers to narrow your search. Enter incomplete telephone numbers to broaden your search.
Calling Number	Calling Number value might not provide valid matches to your query, because in some cases there are no Calling Number value present in the Call Detail Record (CDR). •There is no Calling Number value in the CDR for a call originating outside your Cisco Communications Network (CCN). •There is no Calling Number value in the CDR for an incoming call on an analog trunk when caller ID is unavailable. Therefore, data entry in the Calling Number field is disabled by default. If your search query is too broad to produce the desired result, you can narrow your search by entering a Calling Number value. Enter all (or the trailing part) of the telephone number from which the call originated. Only numerals are valid in this field; all other characters are ignored. To narrow your search, enter more query details or more search criteria.
Cancel	Close the Voice Trace Query window.
Match Called Number	Select (or clear) check box to enable (or disable) Called Number Matching.
Match Called Time	Select (or clear) this check box to enable (or disable) Called Time Matching.
Match Calling Number	Select (or clear) this check box to enable (or disable) Calling Number Matching. Calling Number Matching is disabled by default.
Select Clusters	Select this button to display the Select Cluster to Query dialog box from which you can select Cisco CallManager clusters to query.
Get Records	Retrieve and display a list of CDRs that match your search query criteria.
Help	View this Online help topic.
Start Trace	Select a CDR from the displayed results and click Start Trace to begin a path trace between the specified end-points. Results appear in the Path Analysis Main Window.
Stop Trace	Abort a trace in progress.
Time Call Placed	Specify the approximate time at which the call began, and select a time zone from the drop-down menu.
+/- (min)	Specify your estimate of the Time Call Placed value.

CDR results appear in the large white space within the Voice Trace Query window. This area contains a collapsible tree display of CDRs received from the server.

You can expand a CDR to display additional information about the segment, such as the date and time of the call, the IP address of the VoIP device, the port, and the cause of termination.

Information in the tree view allows you to confirm that you have found the correct CDR before you start to trace the path between the end-points.

Performing Voice Over IP Trace

You can trace the paths that Voice over IP (VoIP) traffic follows on your data network.

Enter only numerals when specifying the telephone number for a VoIP device. Voice Trace ignores spaces, hyphens, and parentheses.

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Step 1 In the Path Analysis Main Window, select Voice Trace.

Step 2 Click Find Call.

The Voice Trace Query window opens.

Step 3 Enter the destination telephone number or IP address in the Called Number field.

Step 4 Check (or uncheck) the Match Called Number check box to enable (or disable) Called Number Matching.

Step 5 Use the Time Call Placed spinner box to specify the approximate time at which the call began, and then select a time zone from the drop-down list box.

Step 6 Check (or uncheck) the Match Call Time check box to enable (or disable) Called Time Matching.

Step 7 Enter a number in the (Min) field that indicates in minutes your uncertainty regarding the correctness of your specified Time Call Placed value.

The default value is 15 minutes.

Step 8 Click Select Clusters.

The Select Clusters to Query dialog box opens. The display window of the dialog box provides a list of available Cisco CallManager clusters you can query. You can perform any of the actions described in Table 12-29.

Table 12-29 Select Clusters to Query Action Description 

Action	Procedure
Query all clusters	Click All Clusters radio button.
Query one or more specific clusters	1. Click the Selected Clusters radio button. 2. Highlight the cluster you want to query by clicking on it in the window. You can make multiple selections by clicking on specific clusters while pressing Ctrl or by clicking the first and last consecutive entries while pressing Shift.
Reload the list of available clusters	1. Click Re-load Clusters button. A Path Analysis dialog box opens. 2. Either: –Click Yes if you want Path Analysis to query the server for Cisco CallManagers and to organize them into clusters. Or –Click No to return to the Select Clusters to Query dialog box without reloading clusters.
Apply your cluster selections and exit the Select Clusters to Query dialog box	Click OK.
Exit the Select Clusters to Query dialog box without making changes	Click Close.

Step 9 Click Get Records to view a collapsible tree view of Call Detail Records (CDRs).

Step 10 Select the CDR for which you want to complete a path trace, and click Start Trace.

The results appear in the Path Analysis Main Window.

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If your query matches more than 100 records, an error message informs you that your search criteria are too broad.

If your query returns too many results, reduce the uncertainty value you specified. If even that fails, add the Calling Number to your search query. This section contains the following topics:

•Tracing From IP Phone to Cisco CallManager

•Tracing From Gateway to Cisco CallManager

•Tracing Completed Calls

•Tracing Call in Progress

•Tracing Potential Calls

Tracing From IP Phone to Cisco CallManager

If you experience problems with the signaling path, such as a missing dial tone, you can trace the signaling path from an IP telephone to Cisco CallManager.

Since there can be several Cisco CallManagers in a network, each IP phone is registered with a particular Cisco CallManager. When tracing the signaling path, it is best to specify the IP address for that Cisco CallManager. To do this:

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Step 1 Get IP addresses in User Tracking for the voice-enabled devices and gateways in your network, including IP phones and Cisco CallManager.

Step 2 In the Path Analysis Main Window, select Data Trace.

Step 3 Enter the IP address for the IP phone in the From field.

Step 4 Enter the IP address for Cisco CallManager in the To field.

Step 5 Click Start Trace.

Path trace results appear in the Trace Results tabbed panel.

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Tracing From Gateway to Cisco CallManager

If you experience problems with the signaling path, such as a missing dial tone, you can trace the signaling path from a gateway to Cisco CallManager.

If the Cisco CallManager operates as an H.323 gateway, the Layer 2 or Layer 3 voice path originates at an IP phone and terminates at the Cisco CallManager. H.323 is a set of standards for the streaming of audio, video, data, or any combination of these, over IP networks.

To trace from gateway to Cisco CallManager:

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Step 1 Get IP addresses in User Tracking for the voice-enabled devices and gateways in your network, including IP phones and Cisco CallManager.

Step 2 In the Path Analysis Main Window, select Data Trace.

Step 3 Enter the IP address for the gateway in the From field.

Step 4 Enter the IP address for Cisco CallManager in the To field.

Step 5 Click Start Trace.

Path trace results appear in the Trace Results tabbed panel.

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Tracing Completed Calls

A completed call is a Voice over IP (VoIP) telephone call that was answered and completed with or without error. Call Detail Records (CDRs) exist for completed calls.

You can trace the path between the source and destination end-points as telephone numbers. You do not need to know the IP addresses. To do this:

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Step 1 Go to the Path Analysis Main Window and select Voice Trace.

Step 2 Click Find Call.

The Voice Trace Query window opens. Use the Online help for Voice Trace Query as you fill in the fields.

Step 3 Click Get Records to retrieve and display a collapsible tree view of CDRs.

Step 4 Select the CDR for which you want a path trace, and click Start Trace.

VoIP path trace results appear in the Path Analysis Main Window.

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Tracing Call in Progress

A call in progress is a Voice over IP (VoIP) telephone call that has begun, but has not concluded.

Although Call Detail Records (CDRs) do not exist for calls in progress, you can trace the path between the source and destination end-points as IP addresses.

To do this:

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Step 1 Get IP addresses in User Tracking or Topology Services for the voice-enabled devices and gateways in your network.

Step 2 Follow the procedures listed in Beginning New Trace.

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Tracing Potential Calls

A potential call is a Voice over IP (VoIP) telephone call that has not yet occurred, but might occur.

Although Call Detail Records (CDRs) do not exist for potential calls, you can trace the most likely path between the source and destination end-points as IP addresses.

To do this:

---

Step 1 Get IP addresses in User Tracking or Topology Services for the voice-enabled devices and gateways in your network.

Step 2 Follow the procedures listed in Beginning New Trace.

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Enabling CDR Logging in Cisco CallManager

Voice over IP (VoIP) traces are possible in Path Analysis only if you have enabled Call Detail Record (CDR) logging for every Cisco CallManager installation in a Cisco CallManager cluster. CDR logging in Cisco CallManager is disabled by default.

To enable CDR logging in Cisco CallManager:

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Step 1 Select Service > Service Parameters in Cisco CallManage.

Step 2 Select the IP address of your Cisco CallManager installation.

Step 3 Select CDREnabled in the Param drop-down list box.

Step 4 Select Boolean in the Type drop-down list box.

Step 5 Select T for true In the Value drop-down list box.

Step 6 Click Update.

CDR logging starts.

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Understanding CDR Query Status Log

While your Voice over IP (VoIP) trace runs, you can view the status of your CDR query in progress.

The CDR query status log is displayed when you select the Status tab in the Voice Trace Query window.

Information shown in the log consists of:

•Telephone numbers you specified for source and destination

•Time range during which the call was placed

•Device names or IP addresses of all queried CDR database servers along the path

When the query concludes, the message CDR record query has finished appears.

If you cancel the query, the message CDR record query has been canceled appears.

Understanding Called Number Matching

You can filter your Voice over IP (VoIP) Call Detail Record (CDR) search query criteria using any combination of the three filters available in the Voice Trace Query window:

•Match Called Time

•Match Called Number

•Match Calling Number

When you enable Called Number Matching, your CDR search criteria includes the call's destination end-point.

When you disable Called Number Matching, this value is excluded. To enable (or disable) Called Number Matching, check (or uncheck) the Match Called Number check box.

Understanding Called Time Matching

You can filter your Voice over IP (VoIP) Call Detail Record (CDR) search query criteria using any combination of the three filters available in the Voice Trace Query window:

•Match Called Time

•Match Called Number

•Match Calling Number

When you enable Called Time Matching, your CDR search criteria include the time the call occurred. When you disable Called Time Matching, this value is excluded.To enable (or disable) Called Time Matching, check (or uncheck) the Match Called Time check box.

Understanding Calling Number Matching

You can filter your Voice over IP (VoIP) Call Detail Record (CDR) search query criteria using any combination of the three filters available in the Voice Trace Query window:

•Match Called Time

•Match Called Number

•Match Calling Number

When you enable Calling Number Matching, your CDR search criteria include the source end-point from which the call originated. When you disable Calling Number Matching, this value is excluded.

Calling Number Matching is disabled by default. The Calling Number value can be an unreliable source of information and might not provide valid matches to your query.

See Understanding Voice Trace Window for more information. If your search query is too broad to produce the desired results, you can narrow your search by providing a Calling Number value.

To do this, check (or uncheck) the Match Calling Number check box.

Using Path Analysis With Other Applications

You can launch other applications from the Path Analysis window:

•Displaying Path in Topology Services

•Starting CiscoView

•Starting Telnet

•Starting Visual Switch Manager

Displaying Path in Topology Services

You can highlight the Layer 2 path for a completed trace in the Topology Services network map. To do this:

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Step 1 Complete a path trace.

Confirm that Layer 2 devices are shown in the Path Analysis map display.

Step 2 Select Campus Manager > Topology Services from the CiscoWorks Homepage to launch Topology Services.

Step 3 Go to the Path Analysis Main Window and select Action > Highlight Path in Network View.

Devices in the Layer 2 trace are highlighted on the Topology Services Network View.

The Highlight Path in Network View command is enabled only if the Layer 2 path exists and has been determined.

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Starting CiscoView

You can display specific device configuration and diagnostic information by highlighting the device in the Map display and starting CiscoView.

CiscoView is a GUI-based device management software application that provides dynamic status, statistics, and comprehensive configuration information for Cisco internetworking devices, allowing configuration and monitoring to the port level.

CiscoView is part of CiscoWorks Common Services, which has already been installed. To start CiscoView:

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Step 1 Right-click a device icon in the Map display.

Step 2 Select CiscoView.

CiscoView starts if it is configured with the information about the selected type of device.

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See the Online help for CiscoView for more information about using CiscoView.

Starting Telnet

You can initiate a remote terminal connection with the Cisco Systems Console on a device that supports Telnet and that appears in the Path Analysis Map display. To do this:

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Step 1 Right-click a device icon in the Map display.

Step 2 Select Telnet.

A Telnet session window opens.

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Starting Visual Switch Manager

You can start Cisco Visual Switch Manager (CVSM) from within Path Analysis. CVSM connections are available to Cisco 1900, 2900XL, and 3500XL devices.

CVSM provides a graphical user interface (GUI) for switch configuration and monitoring switch and network activity. CVSM allows you to monitor a live image of a switch, reconfigure ports and other features, and upgrade the switch software.

To start Visual Switch Manager:

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Step 1 Right-click a device icon in the Map display.

Step 2 Select Visual Switch Manager.

Visual Switch Manager appears in a new browser window.

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Troubleshooting Path Analysis

Before going to the troubleshooting information, you can go through the list of frequently asked questions. This section contains:

•Frequently Asked Questions

•Troubleshooting Suggestions (Data)

•Troubleshooting Suggestions (Voice)

Frequently Asked Questions

Path Analysis users might require answers to commonly asked questions. These questions are divided into two groups in this help topic.

The first group lists questions that refer to Path Analysis in general, while the second group lists questions specific to Voice over IP (VoIP) tracing.

General Questions

•What are the most common operator errors?

•What do the Status Bar and Alert Box Messages mean?

•What Do the Different Kinds of Lines and Icons Represent in the Map Display?

•Can I Have More Than One Path Analysis Window Open and Working at One Time?

•What Are Valid Source and Destination End-Points?

•Does Layer 2 Path Analysis Support Tracing Virtual Connections Inside ATM Clouds?

•How Can I Resolve Web Browser Security Issues?

•Why Do I Have a Layer 2 Path With Some Layer 2 Devices Missing?

•How Can I Troubleshoot a Failed Layer 3 Path Trace?

•If a Previously Discovered End-User Station Becomes Unreachable, How Do I Determine Which Switch Port It Is Connected To?

•Why Does an End-User Station Known to User Tracking Show As Unmanaged in Path Analysis?

VoIP Tracing Questions

•Do I Need to Configure Anything to Enable Voice Traces to Function?

•Am I Required to Use the Voice Trace Button for Voice Traces?

•Should I Use Parentheses or Hyphens When Specifying a Telephone Number for Voice Tracing?

•Should I Specify a Calling Number for Voice Tracing?

•Should I Specify a Called Number for Voice Tracing?

•Should I Specify a Time and Time Range for Voice Tracing?

•How Do I Trace Calls over a PSTN?

•What Is the Best Time Range to Specify for Voice Tracing?

•Can I Perform a Trace on Busy or Unanswered Calls?

Q. What are the most common operator errors?

A. These are two of the more common errors:

–Incomplete subnet to VLAN/ELAN mapping information. See Mapping a Subnet to a VLAN/ELAN for information about subnet mappings.

–Invalid community strings for managed devices, see the Getting Started with the CiscoWorks Server guide for information about setting community strings for managed devices.

See Setting Up Path Analysis for a list of all procedures and prerequisites for Path Analysis to function correctly.

Q. What do the Status Bar and Alert Box Messages mean?

A. The three major status bar and alert box messages are the following:

–The message Trace Completed means the trace succeeded.

–The message Trace Stopped means that you intervened to stop the trace prematurely.

–The message Trace Running means the trace is still under way and has not yet encountered any problems.

All other status bar messages or alert box messages indicate that an error has occurred. See Understanding Status Bar Messages and Understanding Alert Messages.

Q. What Do the Different Kinds of Lines and Icons Represent in the Map Display?

A. The different kinds of lines and icons in the Map display are visual cues, and each has a specific meaning.

Q. Can I Have More Than One Path Analysis Window Open and Working at One Time?

A. Yes. Path Analysis supports multiple, concurrent path traces from a single computer.

You can start additional instances of a running Campus Manager program, such as Path Analysis, only after the first running instance of that program is functional. Wait until the following message does not appear:

Please wait until this window closes before launching another Campus application.

Q. What Are Valid Source and Destination End-Points?

A. Path Analysis uses strict selection criteria for source and destination end-points.

Q. Does Layer 2 Path Analysis Support Tracing Virtual Connections Inside ATM Clouds?

A. Yes, but only for LAN Emulation (LANE).

Q. How Can I Resolve Web Browser Security Issues?

A. If you encounter security errors from Microsoft Internet Explorer 5 while launching or running Path Analysis, you might consider making your CiscoWorks Server a trusted host.

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Step 1 In Internet Explorer, select Tools > Internet Options.

Step 2 Select Security tab.

Step 3 Select the Trusted sites icon.

Step 4 Click Sites button.

Step 5 Enter the IP address of your CiscoWorks Server in the Add this Web site to the zone field.

Step 6 Click Add.

Step 7 Click OK.

The CiscoWorks Server is now listed among your trusted sites.

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Q. Why Do I Have a Layer 2 Path With Some Layer 2 Devices Missing?

A. Two common reasons a Layer 2 path exists with some Layer 2 devices missing are:

–On a Layer 2 path, only Cisco Discovery Protocol (CDP) devices that are known to Topology Services are shown. Hubs or non-Cisco devices are not shown.

–If there has not been a successful Virtual Connection (VC) trace, the Layer 2 path includes only the LAN emulation (LANE) devices on the edges of the ATM cloud, not the ATM switches inside the ATM cloud. See Does Layer 2 Path Analysis Support Tracing Virtual Connections Inside ATM Clouds?

Q. How Can I Troubleshoot a Failed Layer 3 Path Trace?

A. Do the following:

–Compare the message in the status bar to the table shown in Understanding Status Bar Messages.

–Ping the source and/or destination.

–Traceroute the source and/or destination.

Q. If a Previously Discovered End-User Station Becomes Unreachable, How Do I Determine Which Switch Port It Is Connected To?

A. View the User Tracking entry for the unreachable end-user station.

Run a path trace from anywhere else on the network to this end-user station. The last hop appears in the Map display as a dotted line (best guess).

Q. Why Does an End-User Station Known to User Tracking Show As Unmanaged in Path Analysis?

A. Path Analysis relies on User Tracking entries that have been discovered in the last 48 hours.

If you want to use an end-user station as a source or destination end-point for a path trace, you must perform a user and host acquisition in User Tracking or run Discover All in Path Analysis.

VoIP Tracing Questions

Q. Do I Need to Configure Anything to Enable Voice Traces to Function?

A. Yes. You need to do the following:

–Enable Call Detail Record (CDR) logging in Cisco Call Manager

–Enable Simple Network Management Protocol (SNMP) in Cisco Call Manager

–Provide community strings for all Cisco Call Manager devices to the asynchronous network interface Campus Manager Server

–Provide IP addresses for Cisco Call Manager device Discovery

Q. Am I Required to Use the Voice Trace Button for Voice Traces?

A. In most cases, you must select the Voice Trace button in the Path Analysis main window to trace completed Voice over IP (VoIP) telephone calls. However, there are two exceptions.

Do not select the Voice Trace button if you are looking at the signaling path by either:

–Tracing calls between an IP phone and Cisco Call Manager

–Tracing calls between a gateway and Cisco Call Manager

In these cases, select Data Trace.

Q. Should I Use Parentheses or Hyphens When Specifying a Telephone Number for Voice Tracing?

A. Any parentheses, hyphens, spaces, or other non-numeric characters that you enter when specifying a telephone number for voice tracing are automatically deleted from your query.

Q. Should I Specify a Calling Number for Voice Tracing?

A. The Calling Number value might not provide valid Call Detail Record (CDR) matches to your query, so in most cases you should not specify a calling number.

However, if you do not specify a calling number, and if your query results in too many CDRs found, then you can narrow your search criteria by specifying a calling number.

Q. Should I Specify a Called Number for Voice Tracing?

A. Yes. It is best to specify the called number.

Q. Should I Specify a Time and Time Range for Voice Tracing?

A. Yes. It is best to specify the start time and time range for voice tracing.

Q. How Do I Trace Calls over a PSTN?

A. IP phone calls routed over a Public Switched Telephone Network (PSTN) follow a uniform path:

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Step 1 The source IP phone sends Voice over IP (VoIP) packets to the source gateway.

Step 2 Packets flow from the source gateway through the PSTN on their way to the destination gateway.

Step 3 The destination gateway routes packets to the destination IP phone.

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Calls following this path produce one Call Detail Record (CDR) for the first segment of the call and another CDR for the final segment of the call. Each CDR contains a start and end point for its segment of the call. No CDR exists for the PSTN path.

When you search for this kind of call, both CDRs should appear in the Voice Trace Query Results window. You must then select each CDR independently to perform a trace on that segment of the call.

You cannot perform a voice trace on the PSTN segment of the call.

Q. What Is the Best Time Range to Specify for Voice Tracing?

A. In many cases, a 15-minute range before and after the specified time is sufficient to locate a call without exceeding the limit of 100 Call Detail Records (CDRs).

If your query matches more than 100 CDRs, no records are shown. Instead, an error message appears.

If you specify a time range that is too brief, the search might not find your desired CDR.

Q. Can I Perform a Trace on Busy or Unanswered Calls?

A. Yes, but only if you perform a data trace using the IP telephone's address.

You cannot perform a voice trace for busy or unanswered calls by using the calling and called numbers, because busy and unanswered calls generate incomplete Call Detail Records (CDRs).

Troubleshooting Suggestions (Data)

See Frequently Asked Questions before using Table 12-30 to troubleshoot data tracing in Path Analysis.

Table 12-30 Troubleshooting Data Tracing 

Symptom	Probable Cause	Possible Solution
Path Analysis client does not launch.	Path Analysis could take up to several minutes to launch because there are many files that must be loaded and processed from the server. There is a problem with the server.	1. Make sure you wait long enough for Path Analysis to load and process the JAR files from the server. You might want to use Internet Explorer, because it typically performs this operation faster than other browsers. 2. Make sure you have specified the correct URL. 3. Make sure the server is up and running. 4. Select CiscoWorks Server > Administration > Process Management > Process Status to confirm that the Campus Manager Server, DB engine, Gatekeeper, EDS-TR, and EDS services are running on the server. If any required services are not running, start them. 5. Reboot the server.
Path Analysis client launches but error message is displayed.	Server processes are not running normally.	Select CiscoWorks Server > Administration > Process Management > Process Status to confirm that the Campus Manager Server, DB engine, Gatekeeper, EDS-TR, and EDS services are running on the server. If any servers are not running, start them.
When starting a path trace, undefined seed error message is displayed.	Seed device was not specified in Campus Manager Server Discovery settings.	Select CiscoWorks Server > Setup > Campus Manager Server Admin > Discovery Settings to define a seed device.
When starting a path trace, Initial discovery in progress error message is displayed.	After the Campus Manager Server process has begun network Discovery, it takes several minutes (or hours, depending on the size of the network) to complete the Discovery. When device discovery concludes, user and host acquisition Discovery of end-user hosts begins. No path trace is possible until both of these processes are complete.	Wait until device discovery, User Tracking ping sweeps, and User Tracking Discovery have completed before starting a path trace. You can monitor the progress of the Discovery in Path Analysis, which gives an indication of all three processes.
Intermittent or recurring Path Analysis performance lag.	You have a misconfigured or non-functional DNS server. Your network is congested. One or more of your end-points is too busy to respond to SNMP queries.	Confirm that your DNS servers are operational and properly configured.
Path is discovered, but does not seem to function as shown.	An access control list (ACL) is allowing traffic from your CiscoWorks Server to the destination end-point. However, it is blocking traffic between your source and destination end-points.	None.
No Layer 2 path for a given Layer 3 hop.	Layer 2 analysis is possible only when both ends of the Layer 3 hop are managed Cisco devices known to Topology Services, or end-user stations known to User Tracking. A question mark icon on either end of the Layer 3 hop indicates that these prerequisites have not been met.	1. Enable CDP for all Cisco devices. 2. Go to Topology Services, verify that all devices on this subnet are discovered and SNMP-accessible. If they are not, then verify their community strings and run device discovery again. 3. Verify that users and hosts are listed by User Tracking. If they are not, then run user and host acquisition discovery again, preferably with ping sweeps enabled. If VLANs or ELANs are associated with the subnet, verify that the subnet mappings are correct for the Layer 3 hop, and confirm that Topology Services has complete and accurate VLAN/ELAN information for all interfaces.
Not all Layer 2 devices in the physical path are shown.	Path Analysis displays only those Layer 2 Cisco devices known to Topology Services, and end-user stations known to User Tracking. It does not include intervening hubs, non-Cisco or non-CDP devices.	No action required.
No Layer 2 shortcut (multilayer switching) information appears on the map view.	Layer 2 shortcuts are supported on Cisco Catalyst 5000 switches (including the RSM module). Shortcut information appears only when you have specified the correct write community string. The Catalyst 5000 creates shortcuts on the first few packets in a flow, but they can be aged out. It is possible that a shortcut might not be present when you run a path trace. You can create a shortcut by having the source generate a few packets toward the destination before running a path trace.	If you do not see shortcut information on a Catalyst 5000 device, it might be because the shortcut does not exist or you do not have the correct write community string specified. Select CiscoWorks Server > Setup > Campus Manager Server Admin > SNMP Settings to confirm that you have the correct write community string specified. The write community string is used to query the MLS MIB, not to configure the device.
A LANE segment appears in the Layer 2 trace, and shows connectivity between two LANE clients on either side of an ATM cloud. However, it does not show the intervening ATM switches.	There was no data-direct virtual channel between the two LANE clients during the trace. There are unsupported software revisions on ATM switches and LANE cards in the ATM cloud.	See Supported Devices Table for Campus Manager 4.0.3 for a list of supported devices.
Path Analysis did not find a complete Layer 3 path between the source and the destination devices.	There could be many possible causes.	See the status bar for messages and see Monitoring Trace in Progress.
Table view does not contain the full set of information on Layer 3 interfaces.	Path Analysis collects this information on SNMP-reachable Cisco devices, and non-Cisco routers that are in a subnet that is known to be within the organizational domain. The organizational domain comprises the subnets listed in the subnet-to-VLAN/ELAN mapping table.	1. Check the community strings and correct them if necessary. 2. Confirm in Topology Services that Cisco devices are SNMP-accessible (displayed as a green icon). Select View > Display View in Topology Services. 3. Check the subnet-to-VLAN/ELAN mapping table and confirm that the subnet of the device is listed. See Mapping a Subnet to a VLAN/ELAN.

Troubleshooting Suggestions (Voice)

See Frequently Asked Questions before using Table 12-31 to troubleshoot voice tracing in Path Analysis.

Table 12-31 Troubleshooting Voice Tracing 

Symptom	Probable Cause	Possible Solution
No records found in query.	1. The Cisco CallManager server might not have been discovered. 2. The search criteria are too narrow. 3. Call Detail Record (CDR) logging is disabled on the Cisco Call Manager server, or on one or more Cisco CallManagers in a cluster.	1. Start Topology Services and check whether the Cisco CallManager server was discovered. 2. Enter a less restrictive time range, exclude the Calling Number value, and/or enter a less specific called number. 3. Enable CDR logging on Cisco CallManager.
Too many matches found.	The search criteria are too broad.	Enter a more restrictive time range or a more specific calling or called number.
CDR query takes too long.	1. If the search criteria are too broad, the Cisco CallManager server will require a long time to process your query. In organizations with a high call volume, a longer time range (outside the 15-minute recommended range) might be too broad. This makes the Cisco CallManager server to have to search through too many records. 2. Path Analysis cannot access the Cisco CallManager server.	1. Narrow your search criteria by reducing the time range or providing a calling number. 2. Make sure that all Cisco CallManager servers that have been discovered in Topology Services are running and accessible.

Scheduling Jobs for Path Analysis

You can configure scheduling of Path Analysis traces using the Configure Path UT Schedule window. See Scheduling Jobs for Path Analysis for details.

Scheduling Jobs for Exporting User Tracking Data

You can configure archiving of User Tracking data using the Configure Path UT Schedule window. See Scheduling Jobs for Exporting User Tracking Data for details.