ATM OAM Ping

The ATM OAM Ping feature sends an ATM Operation, Administration, and Maintenance (OAM) packet to confirm the connectivity of a specific permanent virtual circuit (PVC). The status of the PVC is displayed when a response to the OAM packet is received. The ATM OAM Ping feature allows the network administrator to verify PVC integrity and facilitates ATM network troubleshooting.

Prerequisites for the ATM OAM Ping Feature

A PVC corresponding to the virtual path identifier (VPI) and virtual channel identifier (VCI) values entered with the ping command should already exist.

Restrictions for the ATM OAM Ping Feature

The ATM OAM Ping feature does not support pings based on the following criteria:

  • Network service access point (NSAP) addresses

  • Multiple-hop loopbacks

  • Loopback location identification

Information About the ATM OAM Ping Feature

Benefits of the ATM OAM Ping Feature

The ATM OAM Ping feature modifies the ping command, which can be used to send an OAM packet to verify PVC connectivity. The status of the PVC is displayed when a response to the OAM packet is received. This is a common method for testing the accessibility of devices.

The ping atm interface atm command provides two ATM OAM ping options:

  • End loopback--Verifies end-to-end PVC integrity.

  • Segment loopback--Verifies PVC integrity to the immediate neighboring ATM device.

The ping atm interface atm command is used to determine the following:

  • Whether a remote host is active or inactive.

  • The round-trip delay in communicating with the host.

  • Packet loss.

The simpler ping command provides an interactive mode for testing ATM network connectivity. The ping command first sends an OAM command loopback cell to the destination and then waits for an OAM response loopback cell. The ping is successful only when the following criteria are met:

  • The OAM command loopback cell reaches the destination.

  • The destination is able to send an OAM loopback response cell back to the source within a predetermined time called a timeout . The default value of the timeout is 2 seconds on Cisco routers.

How to Use the ATM OAM Ping Feature

Testing Network Connectivity Using Ping in Normal Mode

Perform this task to test the network connectivity by using the ping atm interface atm command in normal mode; that is, by entering all values for the ping test on the command line.

SUMMARY STEPS

  1. enable
  2. ping atm interface atm interface-number vpi-value [vci-value [end-loopback [repeat [timeout ]]| seg-loopback [repeat [timeout ]]]]

DETAILED STEPS

  Command or Action Purpose

Step 1

enable

Example:


Router> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

ping atm interface atm interface-number vpi-value [vci-value [end-loopback [repeat [timeout ]]| seg-loopback [repeat [timeout ]]]]

Example:


ping atm interface atm 1/1/0.100 0 500

Example:


end-loopback 1 2

Example:

Displays a response to confirm the connectivity of a specific PVC for the ASR 1000 series router.

  • atm interface-number --ATM interface name.

  • vpi-value --Virtual path identifier. Range: 0 to 255.

  • vci-value --Virtual channel identifier. Range: 0 to 65535.

  • end-loopback --Sends ATM end loopback cells. This is the default.

  • seg-loopback --Sends ATM segment loopback cells.

  • repeat --Number of ping packets that are sent to the destination. Range: 1 to 1000. Default: 5.

  • timeout --Timeout interval, in seconds. Range: 1 to 30. Default: 2.

Testing Network Connectivity Using Ping in Interactive Mode

Perform this task to test network connectivity by using the ping command; that is, by providing values for the ping test by typing the value after the prompts displayed and pressing the Enter key. Press the Enter key without supplying a value to use the default.

SUMMARY STEPS

  1. enable
  2. ping

DETAILED STEPS

  Command or Action Purpose

Step 1

enable

Example:


Router> enable

Enables privileged EXEC mode.

  • Enter your password if prompted.

Step 2

ping

Example:


Router# ping

Displays a response to confirm the connectivity of a specific PVC.

Terminating a Ping Session

To terminate a ping session, type the escape sequence--by default, Ctrl-Shift-6.

Configuration Examples for ATM OAM Ping

Verifying the Connectivity of a Specific PVC Example

The following example verifies the connectivity of a specific PVC by sending an ATM OAM packet and confirms the connectivity when it is successful: 


Router# show atm pvc 10/100 
ATM1/1/0.100: VCD: 3, VPI: 10, VCI: 100 
UBR, PeakRate: 100000 (235850 cps) 
AAL5-LLC/SNAP, etype:0x0, Flags: 0x40, VCmode: 0x0, Encapsize: 12 
OAM frequency: 0 second(s), OAM retry frequency: 1 second(s) 
OAM up retry count: 3, OAM down retry count: 5 
OAM Loopback status: OAM Disabled 
Last cell looped No 
Loop detect state 0, Last cell looped 0, OAM Retries 0, Loop Retries 0 
OAM VC Status: Not Managed 
ILMI VC status: Not Managed 
InARP frequency: 15 minutes(s) 
Transmit priority 3 
InPkts: 78310, OutPkts: 78310, InBytes: 218651435, OutBytes: 218651435 
InPRoc: 0, OutPRoc: 16, Broadcasts: 15 
InFast: 0, OutFast: 0, InAS: 78310, OutAS: 78281 
InPktDrops: 0, OutPktDrops: 0 
CrcErrors: 0, SarTimeOuts: 0, OverSizedSDUs: 0, LengthViolation: 0, CPIErrors: 0 
Out CLP=1 Pkts: 0 
OAM cells received: 315 
F5 InEndloop: 310, F5 InSegloop: 5, F5 InAIS: 0, F5 InRDI: 0 
OAM cells sent: 315 
F5 OutEndloop: 310, F5 OutSegloop: 5, F5 OutAIS: 0, F5 OutRDI: 0 
OAM cell drops: 0 
Status: UP 
VC 10/100 doesn't exist on 2 of 3 ATM interface(s) 
Router#

Normal Mode ping atm interface atm Command Example

The following example shows sample output for the ping atm interface atm command in normal mode: 


Router# ping atm interface atm1/1/0.1 500
Type escape sequence to abort.
Sending 5, 53-byte end-to-end OAM echoes, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/16/52 ms
Router# ping atm interface atm1/1/0.1 0 500 seg-loopback
Type escape sequence to abort.
Sending 5, 53-byte segment OAM echoes, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms
Router# ping atm interface atm1/1/0.1 0 500 end-loopback 100 25
Type escape sequence to abort.
Sending 100, 53-byte end-to-end OAM echoes, timeout is 25 seconds:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!
Success rate is 100 percent (100/100), round-trip min/avg/max = 4/13/180 ms
Router# ping atm interface atm1/1/0.1 0 500 seg-loopback 50 20
Type escape sequence to abort.
Sending 50, 53-byte segment OAM echoes, timeout is 20 seconds:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Success rate is 100 percent (50/50), round-trip min/avg/max = 1/1/4 ms
Router# show atm pvc 10/100
 
ATM1/1/0.100: VCD: 3, VPI: 10, VCI: 100 
UBR, PeakRate: 100000 (235850 cps) 
AAL5-LLC/SNAP, etype:0x0, Flags: 0x40, VCmode: 0x0, Encapsize: 12 
OAM frequency: 10 second(s), OAM retry frequency: 1 second(s) 
OAM up retry count: 3, OAM down retry count: 5 
OAM Loopback status: OAM Received 
Last cell looped No 
Loop detect state 0, Last cell looped 0, OAM Retries 0, Loop Retries 0 
OAM VC Status: Verified 
ILMI VC status: Not Managed 
VC is managed by OAM. 
InARP frequency: 15 minutes(s) 
Transmit priority 3 
InPkts: 78310, OutPkts: 78310, InBytes: 218651435, OutBytes: 218651435 
InPRoc: 0, OutPRoc: 16, Broadcasts: 15 
InFast: 0, OutFast: 0, InAS: 78310, OutAS: 78281 
InPktDrops: 0, OutPktDrops: 0 
CrcErrors: 0, SarTimeOuts: 0, OverSizedSDUs: 0, LengthViolation: 0, CPIErrors: 0 
Out CLP=1 Pkts: 0 
OAM cells received: 331 
F5 InEndloop: 326, F5 InSegloop: 5, F5 InAIS: 0, F5 InRDI: 0 
OAM cells sent: 331 
F5 OutEndloop: 326, F5 OutSegloop: 5, F5 OutAIS: 0, F5 OutRDI: 0 
OAM cell drops: 0 
Status: UP 
VC 10/100 doesn't exist on 2 of 3 ATM interface(s) 
Router#

Interactive ping Command Example

The following is sample output for the ping command in the interactive mode: 


router# ping
 
Protocol [ip]: atm 
ATM Interface: atm1/1/0.100 
VPI value [0]: 10 
VCI value [1]: 100 
Loopback - End(0), Segment(1) [0]: 
Repeat Count [5]: 
Timeout [2]: 
Type escape sequence to abort. 
Sending 5, 53-byte end-to-end OAM echoes, timeout is 2 seconds: 
!!!!! 
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/1 ms 
Router#

Additional References

Related Documents

Related Topic

Document Title

ATM commands

Cisco IOS Asynchronous Transfer Mode Command Reference

ATM Overview

"Overview of the ATM SPAs"

Configuring ATM OAM traffic reduction

"ATM OAM Traffic Reduction"

Detecting failures when using OAM cells and PVC management

"Troubleshooting PVC Failures When Using OAM Cells and PVC Management"

Standards

Standard

Title

ITU-T Specification I.610 (ITU-T specification for B-ISDN operation and maintenance principles and functions).

I.610 Series I: Integrated Services Digital Network Maintenance principles

MIBs

MIB

MIBs Link

None

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

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

RFCs

RFC

Title

None

--

Technical Assistance

Description

Link

The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.

To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.

Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.

http://www.cisco.com/techsupport

Feature Information for ATM OAM Ping

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 ATM OAM Ping

Feature Name

Releases

Feature Information

ATM OAM Ping

Cisco IOS XE Release 2.3

The ATM OAM Ping feature sends an ATM OAM packet to confirm the connectivity of a specific PVC. The status of the PVC is displayed when a response to the OAM packet is received. The ATM OAM Ping feature allows the network administrator to verify PVC integrity and facilitates ATM network troubleshooting.

The following command was introduced or modified: ping atm interface atm .