-
- Cisco Express Forwarding Features Roadmap
- Cisco Express Forwarding Overview
- Configuring Basic Cisco Express Forwarding for Improved Performance, Scalability, and Resiliency in Dynamic Networks
- Enabling or Disabling Cisco Express Forwarding or Distributed Cisco Express Forwarding to Customize Switching/Forwarding for Dynamic Networks
- Configuring a Load-Balancing Scheme for Cisco Express Forwarding Traffic
- Configuring Epochs to Clear and Rebuild Cisco Express Forwarding and Adjacency Tables
- Configuring Cisco Express Forwarding Consistency Checkers for Route Processors and Line Cards
- Configuring Cisco Express Forwarding Network Accounting
- Customizing the Display of Cisco Express Forwarding Event Trace Messages
- Cisco Express Forwarding - SNMP CEF-MIB Support
- Finding Feature Information
- Contents
- Prerequisites for Configuring the Display of Cisco Express Forwarding Event Trace Messages
- Restrictions for Configuring the Display of Cisco Express Forwarding Event Trace Messages
- Information About Configuring the Display of Cisco Express Forwarding Event Trace Messages
Customizing the Display of Cisco Express Forwarding Event Trace Messages
This module contains information about and instructions for customizing the display of recorded Cisco Express Forwarding events.
You can customize the Cisco Express Forwarding event-tracing message display by specifying the size of the file stored in memory or by choosing to display event trace messages by prefix and mask, by a specified interface, or by a Cisco Express Forwarding Virtual Private Network (VPN) routing and forwarding instance (VRF) for an IPv4 or IPv6 address family.
Cisco Express Forwarding is an advanced Layer 3 IP switching technology. It optimizes network performance and scalability for all kinds of networks: those that carry small amounts of traffic and those that carry large amounts of traffic in complex patterns, such as the Internet and networks characterized by intensive web-based applications or interactive sessions.
Finding Feature Information
For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the "Feature Information for Configuring the Display of Cisco Express Forwarding Event Trace Messages" section.
Use Cisco Feature Navigator to find information about platform support and Cisco IOS XE software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Contents
•Prerequisites for Configuring the Display of Cisco Express Forwarding Event Trace Messages
•Restrictions for Configuring the Display of Cisco Express Forwarding Event Trace Messages
•Information About Configuring the Display of Cisco Express Forwarding Event Trace Messages
•How to Customize the Display of Cisco Express Forwarding Event Trace Messages
•Configuration Examples for Configuring the Display of Cisco Express Forwarding Event Trace Messages
•Feature Information for Configuring the Display of Cisco Express Forwarding Event Trace Messages
Prerequisites for Configuring the Display of Cisco Express Forwarding Event Trace Messages
Cisco Express Forwarding must be running on the networking device before you can customize the display of recorded Cisco Express Forwarding events.
Restrictions for Configuring the Display of Cisco Express Forwarding Event Trace Messages
If you enable Cisco Express Forwarding and then create an access list that uses the log keyword, the packets that match the access list are not Cisco Express Forwarding switched. They are process switched. Logging disables Cisco Express Forwarding.
Information About Configuring the Display of Cisco Express Forwarding Event Trace Messages
Before customizing Cisco Express Forwarding event logging, you should understand the following concepts:
•Cisco Platform Support for Central Cisco Express Forwarding and Distributed Cisco Express Forwarding
•Overview of Cisco Express Forwarding Event Trace Function
•Cisco Express Forwarding Event Tracing Defaults and Options
Cisco Platform Support for Central Cisco Express Forwarding and Distributed Cisco Express Forwarding
Cisco Express Forwarding is enable by default on the Cisco ASR 1000 Series Aggregation Services Routers.
To find out if Cisco Express Forwarding is enabled on your platform, enter the show ip cef command. If Cisco Express Forwarding is enabled, you receive output that looks like this:
Router# show ip cef
Prefix Next Hop Interface
[...]
10.2.61.8/24 192.168.100.1 FastEthernet1/0/0
192.168.101.1 FastEthernet2/1/0
[...]
If Cisco Express Forwarding is not enabled on your platform, the output for the show ip cef command looks like this:
Router# show ip cef
%CEF not running
If Cisco Express Forwarding is not enabled on your platform, use the ip cef command to enable (central) Cisco Express Forwarding or the ip cef distributed command to enable distributed Cisco Express Forwarding.
Overview of Cisco Express Forwarding Event Trace Function
The Cisco Express Forwarding event trace function collects Cisco Express Forwarding events as they occur, even when debugging is not enabled. This function allows the tracing of an event immediately after it occurs. Cisco technical personnel can use the event trace function to help resolve any problems with the Cisco Express Forwarding feature.
Cisco Express Forwarding event trace messages are saved in memory on the device. When the event trace messages exceed the configured size, the newest message in the trace will begin to overwrite the older messages. You can use the following commands to change the capacity of the Cisco Express Forwarding event message file:
•The monitor event-trace cef events size global configuration command allows you to increase or decrease the number of messages that can be written to memory for a single instance of a trace. To display the size parameter, use the show monitor event-trace events parameters command.
•The monitor event-trace cef events clear privileged EXEC command allows you to clear existing trace messages.
•The monitor event-trace cef (global) command configures event tracing for Cisco Express Forwarding events. To monitor and control the event trace function for Cisco Express Forwarding events, use the monitor event-trace cef (EXEC) command.
You can use the following commands to display Cisco Express Forwarding events:
•The show monitor event-trace cef all command displays all event trace messages currently in memory for Cisco Express Forwarding.
•The debug ip cef command and the events keyword record general Cisco Express Forwarding events as they occur.
•The debug ip cef table command enables the real-time collection of events that affect entries in the Cisco Express Forwarding tables.
Cisco Express Forwarding Event Tracing Defaults and Options
Event tracing for distributed Cisco Express Forwarding events is enabled by default. The Cisco IOS XE software allows Cisco Express Forwarding to define whether support for event tracing is enabled or disabled by default. The command interface for event tracing allows you to change the default value in one of two ways: using the monitor event-trace cef command in privileged EXEC mode or using the monitor event-trace cef command in global configuration mode.
To configure the file in which you want to save trace information, use the monitor event-trace cef command in global configuration mode. By default, the trace messages are saved in a binary format. If you want to save trace messages in ASCII format, possibly for additional application processing, use the monitor event-trace cef dump pretty command in privileged EXEC mode. The amount of data collected from a trace depends on the trace message size configured using the monitor event-trace cef command in global configuration mode for each instance of a trace.
To specify the trace call stack at tracepoints, you must first clear the trace buffer.
Cisco Express Forwarding Event Tracing for IPv4 Events Defaults and Options
Event tracing for Cisco Express Forwarding IPv4 events is enabled by default.The Cisco IOS XE software allows Cisco Express Forwarding to define whether support for event tracing is enabled or disabled by default. The command interface for event tracing allows you to change the default value in one of two ways: using the monitor event-trace cef ipv4 command in privileged EXEC mode or using the monitor event-trace cef ipv4 command in global configuration mode.
To configure the file in which you want to save trace information for Cisco Express Forwarding IPv4 events, use the monitor event-trace cef ipv4 command in global configuration mode. By default, the trace messages are saved in a binary format. If you want to save trace messages in ASCII format, possibly for additional application processing, use the monitor event-trace cef ipv4 dump pretty command in privileged EXEC mode. The amount of data collected from the trace depends on the trace message size configured using the monitor event-trace cef ipv4 command for each instance of a trace.
To determine whether event tracing is enabled by default for Cisco Express Forwarding, use the show monitor event-trace cef ipv4 command to display trace messages.
To specify the trace call stack at tracepoints, you must first clear the trace buffer.
Cisco Express Forwarding Event Tracing for IPv6 Events Defaults and Options
Event tracing for Cisco Express Forwarding IPv6 events is enabled by default.The Cisco IOS XE software allows Cisco Express Forwarding to define whether support for event tracing is enabled or disabled by default. The command interface for event tracing allows you to change the default value in one of two ways: using the monitor event-trace cef ipv6 command in privileged EXEC mode or using the monitor event-trace cef ipv6 command in global configuration mode.
To configure the file in which you want to save trace information for Cisco Express Forwarding IPv6 events, use the monitor event-trace cef ipv6 command in global configuration mode. By default, the trace messages are saved in a binary format. If you want to save trace messages in ASCII format, possibly for additional application processing, use the monitor event-trace cef ipv6 dump pretty command in privileged EXEC mode. The amount of data collected from the trace depends on the trace message size configured using the monitor event-trace cef ipv6 command for each instance of a trace.
To determine whether event tracing is enabled by default for Cisco Express Forwarding, use the show monitor event-trace cef ipv6 command to display trace messages.
To specify the trace call stack at tracepoints, you must first clear the trace buffer.
How to Customize the Display of Cisco Express Forwarding Event Trace Messages
Perform the following tasks to customize the Cisco Express Forwarding event tracing function and to display event trace messages:
•Customizing Cisco Express Forwarding Event Tracing (optional)
•Customizing Cisco Express Forwarding Event Tracing for IPv4 Events (optional)
•Customizing Cisco Express Forwarding Event Tracing for IPv6 Events (optional)
•Displaying Cisco Express Forwarding Event Trace Information (optional)
Customizing Cisco Express Forwarding Event Tracing
Perform the following task to customize Cisco Express Forwarding event tracing. Event trace messages can be used to monitor Cisco Express Forwarding and to help resolve any issues with the Cisco Express Forwarding feature.
SUMMARY STEPS
1. enable
2. configure terminal
3. monitor event-trace cef {dump-file dump-file-name | {events | interface} {disable | dump-file dump-file-name | enable | size number | stacktrace [depth]}}
4. exit
5. monitor event-trace cef {dump [merged pretty | pretty] | {events | interface | ipv4 | ipv6} {clear | continuous [cancel] | disable | dump [pretty] | enable | one-shot}}
6. disable
DETAILED STEPS
Customizing Cisco Express Forwarding Event Tracing for IPv4 Events
Perform the following task to customize Cisco Express Forwarding event tracing for Cisco Express Forwarding IPv4 events. Use event tracing to monitor Cisco Express Forwarding IPv4 events as they occur and to help resolve any issues with Cisco Express Forwarding and related IPv4 events.
SUMMARY STEPS
1. enable
2. configure terminal
3. monitor event-trace cef ipv4 {disable | distribution |dump-file dump-file-name | enable | match {global | ip-address mask} | size number | stacktrace [depth] | vrf vrf-name [distribution | match {global | ip-address mask}]}
4. exit
5. monitor event-trace cef ipv4 {clear | continuous [cancel] | disable | dump [pretty] | enable | one-shot}
6. disable
DETAILED STEPS
Customizing Cisco Express Forwarding Event Tracing for IPv6 Events
Perform the following task to customize Cisco Express Forwarding event tracing for Cisco Express Forwarding IPv6 events.Use event tracing to monitor Cisco Express Forwarding IPv6 events as they occur and to help resolve any issues with Cisco Express Forwarding and related IPv6 events.
SUMMARY STEPS
1. enable
2. configure terminal
3. monitor event-trace cef ipv6 {disable | distribution | dump-file dump-file-name | enable | match {global | ipv6-address/n | size number | stacktrace [depth] | vrf vrf-name [distribution | match {global | ipv6-address/n}]}
4. exit
5. monitor event-trace cef ipv6 {clear | continuous [cancel] | disable | dump [pretty] | enable | one-shot}}
6. disable
DETAILED STEPS
Displaying Cisco Express Forwarding Event Trace Information
Perform the following task to display Cisco Express Forwarding event trace information.
SUMMARY STEPS
1. enable
2. monitor event-trace cef events clear
3. debug ip cef table
4. show monitor event-trace cef all
5. show monitor event-trace cef latest
6. show monitor event-trace cef events all
7. show monitor event-trace cef interface latest
8. show monitor event-trace cef ipv4 all
9. show monitor event-trace cef ipv6 parameters
10. disable
DETAILED STEPS
Step 1 enable
Use this command to enable privileged EXEC mode. Enter your password if prompted. For example:
Router> enable
Router#
Step 2 monitor event-trace cef events clear
Use this command to clear the Cisco Express Forwarding event trace buffer. For example:
Router# monitor event-trace cef clear
Step 3 debug ip cef table
Use this command to display events that affect entries in the Cisco Express Forwarding tables. For example:
Router# debug ip cef table
01:25:46:CEF-Table:Event up, 10.1.1.1/32 (rdbs:1, flags:1000000)
01:25:46:CEF-IP:Checking dependencies of 0.0.0.0/0
01:25:47:CEF-Table:attempting to resolve 10.1.1.1/32
01:25:47:CEF-IP:resolved 10.1.1.1/32 via 10.9.104.1 to 10.9.104.1 Ethernet2/0/0
01:26:02:CEF-Table:Event up, default, 0.0.0.0/0 (rdbs:1, flags:400001)
01:26:02:CEF-IP:Prefix exists - no-op change
Step 4 show monitor events-trace cef all
Use this command to display event trace messages for Cisco Express Forwarding. For example:
Router# show monitor event-trace cef all
cef_events:
*Jul 22 20:14:58.999: SubSys ipv4fib_ios_def_cap init
*Jul 22 20:14:58.999: SubSys ipv6fib_ios_def_cap init
*Jul 22 20:14:58.999: Inst unknown -> RP
*Jul 22 20:14:58.999: SubSys fib_ios_chain init
*Jul 22 20:14:59.075: SubSys fib init
*Jul 22 20:14:59.075: SubSys ipv4fib init
*Jul 22 20:14:59.075: SubSys fib_ios init
*Jul 22 20:14:59.075: SubSys fib_ios_if init
*Jul 22 20:14:59.075: SubSys ipv4fib_ios init
*Jul 22 20:14:59.075: Flag Common CEF enabled set to yes
*Jul 22 20:14:59.075: Flag IPv4 CEF enabled set to yes
*Jul 22 20:14:59.075: Flag IPv4 CEF switching enabled set to yes
*Jul 22 20:14:59.075: GState CEF enabled
*Jul 22 20:14:59.075: SubSys ipv6fib_ios init
*Jul 22 20:14:59.075: SubSys ipv4fib_util init
*Jul 22 20:14:59.075: SubSys ipv4fib_les init
*Jul 22 20:15:02.907: Process Background created
*Jul 22 20:15:02.907: Flag IPv4 CEF running set to yes
*Jul 22 20:15:02.907: Process Background event loop enter
*Jul 22 20:15:02.927: Flag IPv4 CEF switching running set to yes
cef_interface:
*Jul 22 20:14:58.999: Et0/0 (hw 3) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et0/1 (hw 4) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et0/2 (hw 5) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et0/3 (hw 6) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et1/0 (hw 7) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et1/1 (hw 8) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et1/2 (hw 9) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et1/3 (hw 10) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Se2/0 (hw 11) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Se2/1 (hw 12) SWvecLES <unknown> (0x01096A3C)
.
.
.
The output is in table format where the first column contains a time stamp, the second column lists the type of event, and the third column lists the detail for the event.
Step 5 show monitor event-trace cef latest
Use this command to display only the event trace message that have been sent since the last instance of the show monitor event-trace cef command. For example:
Router# show monitor event-trace cef latest
cef_events:
cef_interface:
*Jul 22 20:14:59.075: Se3/0 (sw 15) FlagCha 0x60C1 add puntLC
*Jul 22 20:14:59.075: <empty> (hw 16) State down -> up
*Jul 22 20:14:59.075: <empty> (hw 16) Create new
*Jul 22 20:14:59.075: Se3/1 (hw 16) NameSet
*Jul 22 20:14:59.075: Se3/1 (hw 16) HWIDBLnk Serial3/1(16)
*Jul 22 20:14:59.075: Se3/1 (hw 16) RCFlags None -> Fast
*Jul 22 20:14:59.075: <empty> (sw 16) VRFLink IPv4:id0 - success
*Jul 22 20:14:59.075: <empty> (sw 16) State deleted -> down
*Jul 22 20:14:59.075: <empty> (sw 16) Create new
*Jul 22 20:14:59.075: Se3/1 (sw 16) NameSet
*Jul 22 20:14:59.075: Se3/1 (sw 16) FIBHWLnk Serial3/1(16)
*Jul 22 20:14:59.075: Se3/1 (sw 16) SWIDBLnk Serial3/1(16)
*Jul 22 20:14:59.075: Se3/1 (sw 16) FlagCha 0x6001 add p2p|input|first
*Jul 22 20:14:59.075: Se3/1 (sw 16) FlagCha 0x6041 add auto_adj
*Jul 22 20:14:59.075: Se3/1 (sw 16) Impared lc rea Queueing configuration
*Jul 22 20:14:59.075: Se3/1 (sw 16) FlagCha 0x60C1 add puntLC
*Jul 22 20:14:59.075: <empty> (hw 17) State down -> up
*Jul 22 20:14:59.075: <empty> (hw 17) Create new
*Jul 22 20:14:59.075: Se3/2 (hw 17) NameSet
Step 6 show monitor event-trace cef events all
Use this command to display information about Cisco Express Forwarding events. For example:
Router# show monitor event-trace cef events all
*Jul 13 17:38:27.999: SubSys ipv4fib_ios_def_cap init
*Jul 13 17:38:27.999: SubSys ipv6fib_ios_def_cap init
*Jul 13 17:38:27.999: Inst unknown -> RP
*Jul 13 17:38:27.999: SubSys fib_ios_chain init
*Jul 13 17:38:28.199: SubSys fib init
*Jul 13 17:38:28.199: SubSys ipv4fib init
*Jul 13 17:38:28.199: SubSys fib_ios init
*Jul 13 17:38:28.199: SubSys fib_ios_if init
*Jul 13 17:38:28.199: SubSys ipv4fib_ios init
*Jul 13 17:38:28.199: Flag Common CEF enabled set to yes
*Jul 13 17:38:28.199: Flag IPv4 CEF enabled set to yes
*Jul 13 17:38:28.199: Flag IPv4 CEF switching enabled set to yes
*Jul 13 17:38:28.199: GState CEF enabled
*Jul 13 17:38:28.199: SubSys ipv6fib_ios init
*Jul 13 17:38:28.199: SubSys ipv4fib_util init
*Jul 13 17:38:28.199: SubSys ipv4fib_les init
*Jul 13 17:38:34.059: Process Background created
*Jul 13 17:38:34.059: Flag IPv4 CEF running set to yes
*Jul 13 17:38:34.059: Process Background event loop enter
*Jul 13 17:38:34.079: Flag IPv4 CEF switching running set to yes
The output is in table format where the first column contains a time stamp, the second column lists the type of event, and the third column lists the detail for the event.
For example, the Subsys event type is related to the initialization of a subset of Cisco Express Forwarding functionality. The "ipv4fib_ios_def_cap init" entry is the initialization of IPv4 Cisco Express Forwarding default capabilities.
Step 7 show monitor event-trace cef interface latest
Use this command to display only the event trace messages generated since the last show monitor event-trace cef interface command was entered. For example:
Router# show monitor event-trace cef interface latest
*Jul 22 20:14:58.999: Et0/0 (hw 3) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et0/1 (hw 4) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et0/2 (hw 5) SWvecLES <unknown> (0x01096A3C)
*Jul 22 20:14:58.999: Et0/3 (hw 6) SWvecLES <unknown> (0x01096A3C)
.
.
.
*Jul 22 20:14:59.075: <empty> (hw 3) State down -> up
*Jul 22 20:14:59.075: <empty> (hw 3) Create new
*Jul 22 20:14:59.075: Et0/0 (hw 3) NameSet
*Jul 22 20:14:59.075: Et0/0 (hw 3) HWIDBLnk Ethernet0/0(3)
*Jul 22 20:14:59.075: Et0/0 (hw 3) RCFlags None -> Fast
*Jul 22 20:14:59.075: <empty> (sw 3) VRFLink IPv4:id0 - success
*Jul 22 20:14:59.075: <empty> (sw 3) State deleted -> down
*Jul 22 20:14:59.075: <empty> (sw 3) Create new
*Jul 22 20:14:59.075: Et0/0 (sw 3) NameSet
*Jul 22 20:14:59.075: Et0/0 (sw 3) FIBHWLnk Ethernet0/0(3)
*Jul 22 20:14:59.075: Et0/0 (sw 3) SWIDBLnk Ethernet0/0(3)
*Jul 22 20:14:59.075: Et0/0 (sw 3) FlagCha 0x6000 add input|first
*Jul 22 20:14:59.075: Et0/0 (sw 3) State down -> up
*Jul 22 20:14:59.075: <empty> (hw 4) State down -> up
*Jul 22 20:14:59.075: <empty> (hw 4) Create new
*Jul 22 20:14:59.075: Et0/1 (hw 4) NameSet
*Jul 22 20:14:59.075: Et0/1 (hw 4) HWIDBLnk Ethernet0/1(4)
*Jul 22 20:14:59.075: Et0/1 (hw 4) RCFlags None -> Fast
*Jul 22 20:14:59.075: <empty> (sw 4) VRFLink IPv4:id0 - success
*Jul 22 20:14:59.075: <empty> (sw 4) State deleted -> down
*Jul 22 20:14:59.075: <empty> (sw 4) Create new
*Jul 22 20:14:59.075: Et0/1 (sw 4) NameSet
*Jul 22 20:14:59.075: Et0/1 (sw 4) FIBHWLnk Ethernet0/1(4)
*Jul 22 20:14:59.075: Et0/1 (sw 4) SWIDBLnk Ethernet0/1(4)
*Jul 22 20:14:59.075: Et0/1 (sw 4) FlagCha 0x6000 add input|first
*Jul 22 20:14:59.075: Et0/1 (sw 4) State down -> up
.
.
.
Step 8 show monitor event-trace cef ipv4 all
Use this command to display information about Cisco Express Forwarding IPv4 events. For example:
Router# show monitor event-trace cef ipv4 all
*Jul 22 20:14:59.075: [Default] *.*.*.*/* Allocated FIB table
[OK]
*Jul 22 20:14:59.075: [Default] *.*.*.*/*'00 Add source Default table
[OK]
*Jul 22 20:14:59.075: [Default] 0.0.0.0/0'00 FIB add src DRH (ins)
[OK]
*Jul 22 20:14:59.075: [Default] *.*.*.*/*'00 New FIB table
[OK]
*Jul 22 20:15:02.927: [Default] *.*.*.*/*'00 FIB refresh start
[OK]
.
.
.
Step 9 show monitor event-trace cef ipv6 parameters
Use this commands to display parameters configured for Cisco Express Forwarding IPv6 events. For example:
Router# show monitor event-trace cef ipv6 parameters
Trace has 1000 entries
Stacktrace is disabled by default
Matching all events
Step 10 disable
Use this command to exit to user EXEC mode. For example:
Router# disable
Router>
Configuration Examples for Configuring the Display of Cisco Express Forwarding Event Trace Messages
This section contains the following configuration examples for customizing the display of recorded Cisco Express Forwarding events:
•Customizing Cisco Express Forwarding Event Tracing: Examples
•Example: Customizing Cisco Express Forwarding Event Tracing for IPv4 Events
•Example: Customizing Cisco Express Forwarding Event Tracing for IPv6 Events
Customizing Cisco Express Forwarding Event Tracing: Examples
The following example shows how to enable event tracing for Cisco Express Forwarding and configure the buffer size to 2500 messages. The trace messages file is set to cef-dump in slot0 (flash memory).
configure terminal
!
monitor event-trace cef events enable
monitor event-trace cef dump-file slot0:cef-dump
monitor event-trace cef events size 2500
exit
The following example shows what happens when you try to enable event tracing for Cisco Express Forwarding events when it is already enabled:
configure terminal
!
monitor event-trace cef events enable
00:04:33: %EVENT_TRACE-6-ENABLE: Trace already enabled.
The following example shows the privileged EXEC commands that stop event tracing, clear the current contents of memory, and reenable the trace function for Cisco Express Forwarding events. This example assumes that the tracing function is configured and enabled on the networking device.
enable
!
monitor event-trace cef events disable
monitor event-trace cef events clear
monitor event-trace cef events enable
disable
Example: Customizing Cisco Express Forwarding Event Tracing for IPv4 Events
The following example shows how to enable event tracing for Cisco Express Forwarding IPv4 events and configure the buffer size to 5000 messages:
configure terminal
!
monitor event-trace cef ipv4 enable
monitor event-trace cef ipv4 size 5000
exit
The following example shows how to enable event tracing for events that match Cisco Express Forwarding IPv4 VRF vpn1:
configure terminal
!
monitor event-trace cef ipv4 enable
monitor event-trace cef ipv4 vrf vpn1
exit
The following example shows the privileged EXEC commands to configure the continuous display of the latest Cisco Express Forwarding event trace entries for IPv4 events:
enable
!
monitor event-trace cef ipv4 continuous
disable
The following example shows how to stop the continuous display of the latest trace entries:
enable
!
monitor event-trace cef ipv4 continuous cancel
disable
Example: Customizing Cisco Express Forwarding Event Tracing for IPv6 Events
The following example shows how to enable event tracing for Cisco Express Forwarding IPv6 events and configure the buffer size to 10000:
configure terminal
!
monitor event-trace cef ipv6 enable
monitor event-trace cef ipv6 size 10000
exit
Additional References
Related Documents
|
|
---|---|
Cisco IOS commands |
|
Commands for configuring and managing Cisco Express Forwarding |
|
List of the features documented in the Cisco Express Forwarding modules |
|
Overview of the Cisco Express Forwarding feature |
|
Tasks for verifying basic Cisco Express Forwarding and distributed Cisco Express Forwarding operation |
Configuring Basic Cisco Express Forwarding for Improved Performance, Scalability, and Resiliency in Dynamic Networks |
Tasks for enabling or disabling Cisco Express Forwarding or distributed Cisco Express Forwarding |
Enabling or Disabling Cisco Express Forwarding or Distributed Cisco Express Forwarding to Customize Switching and Forwarding for Dynamic Networks |
Tasks for configuring load-balancing schemes for Cisco Express Forwarding |
Configuring a Load-Balancing Scheme for Cisco Express Forwarding Traffic |
Tasks for configuring Cisco Express Forwarding consistency checkers |
Configuring Cisco Express Forwarding Consistency Checkers for Route Processors and Line Cards |
Tasks for configuring epochs for Cisco Express Forwarding tables |
Configuring Epochs to Clear and Rebuild Cisco Express Forwarding and Adjacency Tables |
Tasks for configuring and verifying Cisco Express Forwarding network accounting |
Standards
|
|
---|---|
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature. |
— |
MIBs
RFCs
|
|
---|---|
No new or modified RFCs are supported by this feature, and support for existing RFCs has not been modified by this feature. |
— |
Technical Assistance
Feature Information for Configuring the Display of Cisco Express Forwarding Event Trace Messages
Table 1 lists the features in this module.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which Cisco IOS XE software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Note Table 1 lists only the Cisco IOS XE software release that introduced support for a given feature in a given Cisco IOS XE software release train. Unless noted otherwise, subsequent releases of that Cisco IOS XE software release train also support that feature.
Glossary
adjacency—A relationship formed between selected neighboring routers and end nodes for the purpose of exchanging routing information. Adjacency is based upon the use of a common media segment by the routers and nodes involved.
Cisco Express Forwarding—A Layer 3 switching technology. Cisco Express Forwarding can also refer to central Cisco Express Forwarding mode, one of two modes of Cisco Express Forwarding operation. Cisco Express Forwarding enables a Route Processor to perform express forwarding. Distributed Cisco Express Forwarding is the other mode of Cisco Express Forwarding operation.
distributed Cisco Express Forwarding—A mode of Cisco Express Forwarding operation in which line cards maintain identical copies of the forwarding information base (FIB) and adjacency tables. The line cards perform the express forwarding between port adapters; this relieves the Route Processor of involvement in the switching operation.
FIB—forwarding information base. A component of Cisco Express Forwarding that is conceptually similar to a routing table or information base. The router uses the FIB lookup table to make destination-based switching decisions during Cisco Express Forwarding operation. The router maintains a mirror image of the forwarding information in an IP routing table.
line card—A general term for an interface processor that can be used in various Cisco products.
prefix—The network address portion of an IP address. A prefix is specified by a network and mask and is generally represented in the format network/mask. The mask indicates which bits are the network bits. For example, 1.0.0.0/16 means that the first 16 bits of the IP address are masked, making them the network bits. The remaining bits are the host bits. In this example, the network number is 10.0.
VPN—Virtual Private Network. The result of a router configuration that enables IP traffic to use tunneling to travel securely over a public TCP/IP network.
VRF—A Virtual Private Network (VPN) routing/forwarding instance. A VRF consists of an IP routing table, a derived forwarding table, a set of interfaces that use the forwarding table, and a set of rules and routing protocols that determine what goes into the forwarding table. In general, a VRF includes the routing information that defines a customer VPN site that is attached to a PE router.