Configuring IP SLAs ICMP Path Echo Operations

Last Updated: July 18, 2011

This module describes how to configure an IP Service Level Agreements (SLAs) Internet Control Message Protocol (ICMP) Path Echo operation to monitor end-to-end and hop-by-hop response time between a Cisco router and devices using IP. ICMP Path Echo is useful for determining network availability and for troubleshooting network connectivity issues. The results of the ICMP Path Echo operation can be displayed and analyzed to determine how ICMP is performing.

Finding Feature Information

Your software release may not support all the features documented in this module. 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 Table at the end of this document.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Restrictions for IP SLAs ICMP Path Echo Operations

We recommend using a Cisco networking device as the destination device although any networking device that supports RFC 862, Echo protocol, can be used.

Information About IP SLAs ICMP Path Echo Operations

ICMP Path Echo Operation

To monitor ICMP Path Echo performance on a device, use the IP SLAs ICMP Path Echo operation. An ICMP Path Echo operation measures end-to-end and hop-by-hop response time between a Cisco router and devices using IP. ICMP Path Echo is useful for determining network availability and for troubleshooting network connectivity issues.

The IP SLAs ICMP Path Echo operation records statistics for each hop along the path that the IP SLAs operation takes to reach its destination. The ICMP Path Echo operation determines this hop-by-hop response time between a Cisco router and any IP device on the network by discovering the path using the traceroute facility.

In the figure below the source IP SLAs device uses traceroute to discover the path to the destination IP device. A ping is then used to measure the response time between the source IP SLAs device and each subsequent hop in the path to the destination IP device.

Figure 1 ICMP Path Echo Operation


Using the statistics recorded for the response times and availability, the ICMP Path Echo operation can identify a hop in the path that is causing a bottleneck.

How to Configure IP SLAs ICMP Path Echo Operations

Configuring an ICMP Path Echo Operation on the Source Device


Note
This operation does not require an IP SLAs Responder on the destination device.

Perform only one of the following tasks:

Configuring a Basic ICMP Path Echo Operation on the Source Device

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip sla operation-id

4.    path-echo {destination-ip-address | destination-hostname} [source-ip {ip-address | hostname}]

5.    frequency seconds

6.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
ip sla operation-id


Example:

Router(config)# ip sla 7

 

Specifies an ID number for the operation being configured, and enters IP SLA configuration mode.

 
Step 4
path-echo {destination-ip-address | destination-hostname} [source-ip {ip-address | hostname}]


Example:

Router(config-ip-sla)# path-echo protocol 172.29.139.134

 

Defines a Path Echo operation and enters IP SLA Path Echo configuration mode.

 
Step 5
frequency seconds


Example:

Router(config-ip-sla-pathEcho)# frequency 30

 

(Optional) Sets the rate at which a specified IP SLAs operation repeats.

 
Step 6
end


Example:

Router(config-ip-sla-pathEcho)# end

 

Exits to privileged EXEC mode.

 
Example

The following example shows the configuration of the IP SLAs ICMP Path Echo operation number 7 that will start in 30 seconds and run for 5 minutes. 

ip sla 7
 path-echo 172.29.139.134
 frequency 30
!
ip sla schedule 7 start-time after 00:00:30 life 300

Configuring an ICMP Path Echo Operation with Optional Parameters on the Source Device

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip sla operation-number

4.    path-echo {destination-ip-address | destination-hostname} [source-ip {ip-address | hostname}]

5.    history buckets-kept size

6.    history distributions-of-statistics-kept size

7.    history enhanced [interval seconds] [buckets number-of-buckets]

8.    history filter {none | all | overThreshold | failures}

9.    frequency seconds

10.    history hours-of-statistics-kept hours

11.    history lives-kept lives

12.    owner owner-id

13.    paths-of-statistics-kept size

14.    request-data-size bytes

15.    samples-of-history-kept samples

16.    history statistics-distribution-interval milliseconds

17.    tag text

18.    threshold milliseconds

19.    timeout milliseconds

20.    tos number

21.    verify-data

22.    vrf vrf-name

23.    end


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
ip sla operation-number


Example:

Router(config)# ip sla 10

 

Begins configuration for an IP SLAs operation and enters IP SLA configuration mode.

 
Step 4
path-echo {destination-ip-address | destination-hostname} [source-ip {ip-address | hostname}]


Example:

Router(config-ip-sla)# path-echo 172.29.139.134

 

Defines a Path Echo operation and enters IP SLA Path Echo configuration mode.

 
Step 5
history buckets-kept size


Example:

Router(config-ip-sla-pathEcho)# history buckets-kept 25

 

(Optional) Sets the number of history buckets that are kept during the lifetime of an IP SLAs operation.

 
Step 6
history distributions-of-statistics-kept size


Example:

Router(config-ip-sla-pathEcho)# history distributions-of-statistics-kept 5

 

(Optional) Sets the number of statistics distributions kept per hop during an IP SLAs operation.

 
Step 7
history enhanced [interval seconds] [buckets number-of-buckets]


Example:

Router(config-ip-sla-pathEcho)# history enhanced interval 900 buckets 100

 

(Optional) Enables enhanced history gathering for an IP SLAs operation.

 
Step 8
history filter {none | all | overThreshold | failures}


Example:

Router(config-ip-sla-pathEcho)# history filter failures

 

(Optional) Defines the type of information kept in the history table for an IP SLAs operation.

 
Step 9
frequency seconds


Example:

Router(config-ip-sla-pathEcho)# frequency 30

 

(Optional) Sets the rate at which a specified IP SLAs operation repeats.

 
Step 10
history hours-of-statistics-kept hours


Example:

Router(config-ip-sla-pathEcho)# history hours-of-statistics-kept 4

 

(Optional) Sets the number of hours for which statistics are maintained for an IP SLAs operation.

 
Step 11
history lives-kept lives


Example:

Router(config-ip-sla-pathEcho)# history lives-kept 5

 

(Optional) Sets the number of lives maintained in the history table for an IP SLAs operation.

 
Step 12
owner owner-id


Example:

Router(config-ip-sla-pathEcho)# owner admin

 

(Optional) Configures the Simple Network Management Protocol (SNMP) owner of an IP SLAs operation.

 
Step 13
paths-of-statistics-kept size


Example:

Router(config-ip-sla-pathEcho)# paths-of-statistics-kept 3

 

(Optional) Sets the number of paths for which statistics are maintained per hour for an IP SLAs operation.

 
Step 14
request-data-size bytes


Example:

Router(config-ip-sla-pathEcho)# request-data-size 64

 

(Optional) Sets the protocol data size in the payload of an IP SLAs operation's request packet.

 
Step 15
samples-of-history-kept samples


Example:

Router(config-ip-sla-pathEcho)# samples-of-history-kept 10

 

(Optional) Sets the number of entries kept in the history table per bucket for an IP SLAs operation.

 
Step 16
history statistics-distribution-interval milliseconds


Example:

Router(config-ip-sla-pathEcho)# history statistics-distribution-interval 10

 

(Optional) Sets the time interval for each statistics distribution kept for an IP SLAs operation.

 
Step 17
tag text


Example:

Router(config-ip-sla-pathEcho)# tag TelnetPollServer1

 

(Optional) Creates a user-specified identifier for an IP SLAs operation.

 
Step 18
threshold milliseconds


Example:

Router(config-ip-sla-pathEcho)# threshold 10000

 

(Optional) Sets the upper threshold value for calculating network monitoring statistics created by an IP SLAs operation.

 
Step 19
timeout milliseconds


Example:

Router(config-ip-sla-pathEcho)# timeout 10000

 

(Optional) Sets the amount of time an IP SLAs operation waits for a response from its request packet.

 
Step 20
tos number


Example:

Router(config-ip-sla-pathEcho)# tos 160

 

(Optional) Defines a type of service (ToS) byte in the IP header of an IP SLAs operation.

 
Step 21
verify-data


Example:

Router(config-ip-sla-pathEcho)# verify-data

 

(Optional) Causes an IP SLAs operation to check each reply packet for data corruption.

 
Step 22
vrf vrf-name


Example:

Router(config-ip-sla-pathEcho)# vrf vpn-A

 

(Optional) Allows monitoring within Multiprotocol Label Switching (MPLS) Virtual Private Networks (VPNs) using IP SLAs operations.

 
Step 23
end


Example:

Router(config-ip-sla-pathEcho)# end

 

Exits to privileged EXEC mode.

 

Scheduling IP SLAs Operations


Note
  • All IP SLAs operations to be scheduled must be already configured.
  • The frequency of all operations scheduled in a multioperation group must be the same.
  • List of one or more operation ID numbers to be added to a multioperation group is limited to a maximum of 125 characters, including commas (,).
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    Do one of the following:

  • ip sla schedule operation-number [life {forever | seconds}] [start-time {hh : mm[: ss] [month day | day month] | pending | now | after hh : mm : ss}] [ageout seconds] [recurring]
  • ip sla group schedule group-operation-number operation-id-numbers schedule-period schedule-period-range [ageout seconds] [frequency group-operation-frequency] [life{forever | seconds}] [start-time{hh:mm[:ss] [month day | day month] | pending | now | after hh:mm:ss}]

4.    exit

5.    show ip sla group schedule

6.    show ip sla configuration


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
Do one of the following:
  • ip sla schedule operation-number [life {forever | seconds}] [start-time {hh : mm[: ss] [month day | day month] | pending | now | after hh : mm : ss}] [ageout seconds] [recurring]
  • ip sla group schedule group-operation-number operation-id-numbers schedule-period schedule-period-range [ageout seconds] [frequency group-operation-frequency] [life{forever | seconds}] [start-time{hh:mm[:ss] [month day | day month] | pending | now | after hh:mm:ss}]


Example:

Router(config)# ip sla schedule 10 start-time now life forever



Example:

Router(config)# ip sla group schedule 1 3,4,6-9

 

For individual IP SLAs operations only:

Configures the scheduling parameters for an individual IP SLAs operation.

or

For multioperation scheduler only:

Specifies an IP SLAs operation group number and the range of operation numbers to be scheduled in global configuration mode.

 
Step 4
exit


Example:

Router(config)# exit

 

Exits to privileged EXEC mode.

 
Step 5
show ip sla group schedule


Example:

Router# show ip sla group schedule

 

(Optional) Displays the IP SLAs group schedule details.

 
Step 6
show ip sla configuration


Example:

Router# show ip sla configuration

 

(Optional) Displays the IP SLAs configuration details.

 

Troubleshooting Tips

  • If the IP SLAs operation is not running and generating statistics, add the verify-data command to the configuration of the operation (while configuring in IP SLA configuration mode) to enable data verification. When enabled, each operation response is checked for corruption. Use the verify-data command with caution during normal operations because it generates unnecessary overhead.
  • Use the debugipsla trace and debug ip sla error commands to help troubleshoot issues with an IP SLAs operation.

What to Do Next

To add proactive threshold conditions and reactive triggering for generating traps, or for starting another operation, to an IP SLAs operation, see the "Configuring Proactive Threshold Monitoring" section.

To view and interpret the results of an IP SLAs operation use the show ip sla statistics command. Checking the output for fields that correspond to criteria in your service level agreement will help you determine whether the service metrics are acceptable.

Configuration Examples for IP SLAs ICMP Path Echo Operations

Example Configuring an ICMP Path Echo Operation

The following example shows how to configure an IP SLAs operation type of ICMP Path Echo that will start after 30 seconds and run for 5 minutes. The figure below depicts the ICMP Path Echo operation.

Figure 2 ICMP Path Echo Operation


This example sets a Path Echo operation (ip sla 3) from Router B to Router A using IP/ICMP. The operation attempts to execute three times in 25 seconds (first attempt at 0 seconds).

Router B Configuration

ip sla 3
 path-echo 172.29.139.134
 frequency 10
 tag SGN-RO
 timeout 1000
ip sla schedule 3 life 25

Additional References

Related Documents

Related Topic

Document Title

Cisco IOS commands

Cisco IOS Master Commands List, All Releases

Cisco IOS IP SLAs commands

Cisco IOS IP SLAs Command Reference

Cisco IOS IP SLAs: general information

Cisco IOS IP SLAs Overview chapter of the Cisco IOS IP SLAs Configuration Guide

Standards

Standards

Title

No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.

--

MIBs

MIBs

MIBs Link

CISCO-RTTMON-MIB

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs

RFCs

RFCs

Title

RFC 862

Echo Protocol

Technical Assistance

Description

Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

http://www.cisco.com/cisco/web/support/index.html

Feature Information for IP SLAs ICMP Path Echo Operations

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Table 1 Feature Information for IP SLAs ICMP Path Echo Operations

Feature Name

Releases

Feature Information

IP SLAs ICMP Path Echo Operation

12.2(31)SB2

12.2(33)SRB1

12.2(33)SXH

12.3(14)T

15.0(1)S

Cisco IOS XE 3.1.0SG

The Cisco IOS IP SLAs Internet Control Message Protocol (ICMP) path echo operation allows you to measure end-to-end and hop-by-hop network response time between a Cisco device and other devices using IP.

Cisco and the Cisco Logo are trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and other countries. A listing of Cisco's trademarks can be found at www.cisco.com/go/trademarks. Third party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1005R)

Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.