Asynchronous Transfer Mode Configuration Guide, Cisco IOS Release 15S
OAM Segment Endpoint
OAM Segment Endpoint
Last Updated: November 29, 2012
The OAM Segment Endpoint feature terminates segment Operation, Administration and Maintenance (OAM) cells arriving on the Layer 2 transport virtual circuit (VC). The OAM Segment Endpoint feature helps in checking the segment connectivity. This feature can be used with Any Transport over MPLS (AToM) and Layer 2 Tunnel Protocol Version 3 (L2TPv3).
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 for OAM Segment Endpoint.
Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn . An account on Cisco.com is not required.
Prerequisites for OAM Segment Endpoint
This feature can be enabled under Layer 2 transport permanent virtual circuit (PVC) submode and virtual circuit (VC) class configuration mode.
Restrictions for OAM Segment Endpoint
The following restrictions apply to the OAM Segment Endpoint feature:
Information About OAM Segment Endpoint
To configure the OAM Segment Endpoint feature, you should understand the following concept:
VP VC Segment Endpoint
The Cisco 12000 series Internet router or Cisco 7200 router responds to the incoming segment cells, if the OAM Segment Endpoint feature is configured; otherwise they are transferred on the pseudowire.
Irrespective of whether the is feature is enabled or not, End OAM cells for both VPs and VCs are transferred on the pseudowire. To terminate End OAM cells, you need to enable OAM-emulation.
The figure below shows ATM transport over MPLS.
How to Configure OAM Segment Endpoint
See the following sections for tasks that use the oam-ac segment endpointcommand to terminate the segment OAM cells on a VC:
Configuring OAM Segment Endpoint
This feature coexists with OAM emulation for Layer 2 VCs. If OAM emulation is already enabled, segment endpoint configuration is redundant. On the Cisco 12000 series router, F4/F5 distributed Operations, Administration and Maintenance (dOAM) is enabled by default.
2. configure terminal
3. interface atm slot / port . subinterface-number
4. pvc vpi / vci l2transport
5. oam-ac segment endpoint
6. encapsulation aal5
7. xconnect peer-router-id vcid encapsulation mpls
Verifying OAM Segment Endpoint
To verify whether the OAM Segment Endpoint feature is working correctly, use the following steps to monitor the segment cells (arriving on the Layer 2 transport VC) that are being terminated on ATM links in a network.
2. show atm pvc [ppp | [interface atm interface-number[.subinterface]] [connection-name | vpi / vci [vaccess [detail]] | vci]]
Configuration Examples for OAM Segment Endpoint
This section contains the following configuration and verification examples:
OAM Segment Endpoint Configuration Example
VC Layer 2 Transport
Router(config)# interface atm1/1 Router(config-if)# pvc 0/100 l2transport Router(cfg-if-atm-l2trans-pvc)# oam-ac segment endpoint Router(cfg-if-atm-l2trans-pvc)# end
Router(config)# vc-class atm test Router(config-vc-class)# oam-ac segment endpoint Router(config-vc-class)# end
The following is sample output for the show running-config interfacecommand:
Router# show running-config interface atm1/1 Building configuration... Current configuration : 177 bytes ! interface ATM1/1 no ip address no ip directed-broadcast atm pvp 40 l2transport oam-ac segment endpoint no atm enable-ilmi-trap no atm ilmi-keepalive pvc 0/100 l2transport oam-ac segment endpoint end Router# show running-config Building configuration... Current configuration : 4251 bytes ! vc-class atm test oam-ac segment endpoint oam-pvc manage !
The following is sample output from the show atm pvccommand. It provides the segment OAM cell configuration and status information.
Router# show atm pvc 12/122 VC 12/122 doesn't exist on interface ATM1/0 - cannot display VC 12/122 doesn't exist on interface ATM1/1 - cannot display ATM1/2.3: VCD: 7, VPI: 12, VCI: 122 UBR, PeakRate: N/A (UBR VC) AAL5 L2transport, etype:0xF, Flags: 0x10000C2E, VCmode: 0x0 OAM Cell Emulation: not configured OAM Segment Endpoint: enabled ============> oam-ac segment endpoint enabled Interworking Method: Not Configured Remote Circuit Status = No Alarm, Alarm Type = None InPkts: 0, OutPkts: 0, InBytes: 0, OutBytes: 0 InPRoc: 0, OutPRoc: 0 InFast: 0, OutFast: 0, InAS: 0, OutAS: 0 Out CLP=1 Pkts: 0 OAM cells received: 0 F5 InEndloop: 0, F5 InSegloop: 0, F5 InEndcc: 0, F5 InSegcc: 0, F5 InAIS: 0, F5 InRDI: 0 OAM cells sent: 0 F5 OutEndloop: 0, F5 OutSegloop: 0, F5 OutEndcc: 0, F5 OutSegcc: 0, F5 OutAIS: 0, F5 OutRDI: 0 OAM cell drops: 0 Status: UP Router# show atm pvc 40/3 ATM1/1: VCD: 48, VPI: 40, VCI: 3 UBR, PeakRate: N/A (UBR VC) AAL5-MUX, etype:0x0, Flags: 0xD2C, VCmode: 0x0 OAM frequency: 0 second(s), OAM retry frequency: 0 second(s) OAM up retry count: 0, OAM down retry count: 0 OAM Segment Endpoint: enabled OAM END CC Activate retry count: 0, OAM END CC Deactivate retry count: 0 OAM END CC retry frequency: 0 second(s), OAM SEGMENT CC Activate retry count: 0, OAM SEGMENT CC Deactivate retry count: 0 OAM SEGMENT CC retry frequency: 0 second(s), OAM Loopback status: OAM Disabled OAM VC state: Not Managed ILMI VC state: Not Managed OAM END CC status: OAM CC Ready OAM END CC VC state: Not Managed OAM SEGMENT CC status: OAM CC Ready OAM SEGMENT CC VC state: Not Managed InARP DISABLED InPkts: 0, OutPkts: 0, InBytes: 0, OutBytes: 0 InPRoc: 0, OutPRoc: 0, Broadcasts: 0 InFast: 0, OutFast: 0, InAS: 0, OutAS: 0 Out CLP=1 Pkts: 0 OAM cells received: 0 F4 InEndloop: 0, F4 InSegloop: 0, F4 InAIS: 0, F4 InRDI: 0 OAM cells sent: 0 F4 OutEndloop: 0, F4 OutSegloop: 0, F4 OutAIS: 0, F4 OutRDI: 0 OAM cell drops: 0 Status: UP
1 Not all supported standards are listed.
Feature Information for OAM Segment Endpoint
GUID-00BF69F0-570E-4878-95D9-380735A1F459A lists the features in this module and provides links to specific configuration information.
Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which Cisco IOS and Catalyst OS 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.
customer edge (CE) router --A router that belongs to a customer network, which connects to a provider edge (PE) router to utilize Multiprotocol Label Switching (MPLS) Virtual Private Network (VPN) network services.
provider edge (PE) router --Entry point into the service provider network. The PE router is typically deployed on the edge of the network and is administered by the service provider. The PE router is the redistribution point between Enhanced Interior Gateway Routing Protocol (EIGRP) and Border Gateway Protocol (BGP) in PE to CE networking.
pseudowire (PW)--A mechanism that carries the elements of an emulated service from one provider edge (PE) to one or more PEs over a packet-switched network (PSN).
VPN --virtual private network. Allows IP traffic to travel securely over public TCP/IP networks and the Internet by encapsulating and encrypting all IP packets. VPN uses a tunnel to encrypt all information at the IP level.
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