MPLS Pseudowire Status Signaling

The MPLS Pseudowire Status Signaling feature enables you to configure the router so it can send pseudowire status to a peer router, even when the attachment circuit is down.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and 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.

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.

Prerequisites for MPLS Pseudowire Status Signaling

  • Before configuring this feature, make sure that both peer routers are capable of sending and receiving pseudowire status messages.

Restrictions for MPLS Pseudowire Status Signaling

  • Both peer routers must support the ability to send and receive pseudowire status messages in label advertisement and label notification messages. If both peer routers do not support pseudowire status messages, Cisco recommends that you disable the messages with the no status command.

  • This feature is not integrated with Any Transport over MPLS (AToM) Virtual Circuit Connection Verification (VCCV).

  • This feature is not integrated with Bidirectional Forwarding Detection (BFD).

  • The standby and required switchover values from IETF draft-muley-pwe3-redundancy-02.txt are not supported.

Information About MPLS Pseudowire Status Signaling

How MPLS Pseudowire Status Switching Works

The pseudowire status messages are sent in label advertisement and label notification messages if the peer also supports the MPLS Pseudowire Status Signaling feature. You can issue the show mpls l2transport vc detail command to show that both the local and remote routers support pseudowire status messages. The following example shows the line of output to look for: 

Router# show mpls l2transport vc detail 
.
.
.
status TLV support (local/remote): enabled/supported

How MPLS Pseudowire Status Switching Works using the commands associated with the L2VPN Protocol-Based CLIs feature

The pseudowire status messages are sent in label advertisement and label notification messages if the peer also supports the MPLS Pseudowire Status Signaling feature. You can issue the show l2vpn atom vc detail command to show that both the local and remote routers support pseudowire status messages. The following example shows the line of output to look for: 

Device# show l2vpn atom vc detail 
.
.
.
status TLV support (local/remote): enabled/supported

When One Router Does Not Support MPLS Pseudowire Status Signaling

The peer routers must support the ability to send and receive pseudowire status messages in label advertisement and label notification messages. If one router does not support pseudowire status messages, Cisco recommends that you disable the messages with the no status command. This returns the router to label withdraw mode.

If the peer does not support the MPLS Pseudowire Status Signaling feature, the local router changes its mode of operation to label withdraw mode. You can issue the show mpls l2transport vc detail command to show that the remote router does not support pseudowire status messages. The following example shows the line of output to look for: 

Router# show mpls l2transport vc detail 
.
.
.
status TLV support (local/remote): enabled/not supported


 When you issue the following 
		debug 
		  mpls 
		  l2transport 
		  vccommands, the messages show that the peer router does not supportthe MPLS Pseudowire Status Signaling feature and that the local router is changing to withdraw mode, as shown in bold in the following example: 
	 


 Router# debug mpls l2transport vc event Router# 
		debug 
		  mpls 
		  l2transport 
		  vc 
		  status 
		  event 
		  Router# 
		debug 
		  mpls 
		  l2transport 
		  vc 
		  status 
		  fsm 
		  Router# 
		debug 
		  mpls 
		  l2transport 
		  vc 
		  ldp 
	 


 
	 


 *Feb 26 13:41:40.707: AToM LDP [10.1.1.2]: Sending label withdraw msg *Feb 26 13:41:40.707: AToM LDP [10.1.1.2]: VC Type 5, mtu 1500 *Feb 26 13:41:40.707: AToM LDP [10.1.1.2]: VC ID 100, label 18 *Feb 26 13:41:40.707: AToM LDP [10.1.1.2]: Status 0x0000000A [PW Status NOT supported] 
	 






When One Router Does Not Support MPLS Pseudowire Status Signaling using the commands associated with the L2VPN Protocol-Based CLIs feature



The peer routers must support the ability to send and receive pseudowire status messages in label advertisement and label notification messages. If one router does not support pseudowire status messages, we recommend that you disable the messages with the no status command. This returns the router to label withdraw mode. 



If the peer does not support the MPLS Pseudowire Status Signaling feature, the local router changes its mode of operation to label withdraw mode. You can issue the show l2vpn atom vc detail command to show that the remote router does not support pseudowire status messages. The following example shows the line of output to look for:


Device# show l2vpn atom vc detail 


.


.


.


status TLV support (local/remote): enabled/not supported





When you issue the following debug l2vpn atom vc commands, the messages show that the peer router does not support the MPLS Pseudowire Status Signaling feature and that the local router is changing to withdraw mode, as shown in the following example: 


Device# debug l2vpn atom vc event
Device# debug l2vpn atom vc status event
Device# debug l2vpn atom vc status fsm
Device# debug l2vpn atom vc ldp


*Feb 26 13:41:40.707: AToM LDP [110.1.1.2]: Sending label withdraw msg
*Feb 26 13:41:40.707: AToM LDP [110.1.1.2]:   VC Type   5, mtu 1500
*Feb 26 13:41:40.707: AToM LDP [110.1.1.2]:   VC ID     100, label 18
*Feb 26 13:41:40.707: AToM LDP [110.1.1.2]:   Status 0x0000000A [PW Status NOT supported]







Status Messages Indicating That the Attachment Circuit Is Down



When the attachment circuit is down between the two routers, the output of the show mpls l2transport vc detail command shows the following status:


Router# show mpls l2transport vc detail 


.


.


.


Last remote LDP TLV    status rcvd: AC DOWN(rx,tx faults)





The debug messages also indicate that the attachment circuit is down, as shown in bold in the command output:



Router# debug mpls l2transport vc event
Router# debug mpls l2transport vc status event
Router# debug mpls l2transport vc status fsm
Router# debug mpls l2transport vc ldp


*Feb 26 11:51:42.427: AToM LDP [10.1.1.1]: Received notif msg, id 88
*Feb 26 11:51:42.427: AToM LDP [10.1.1.1]:   Status    0x00000007 [PW Status]
*Feb 26 11:51:42.427: AToM LDP [10.1.1.1]:   PW Status 0x00000006 [AC DOWN(rx,tx faults)]




Other pseudowire status messages include not-forwarding, pw-tx-fault, and pw-rx-fault. 






Status Messages Indicating That the Attachment Circuit Is Down using the commands associated with the L2VPN Protocol-Based CLIs feature



When the attachment circuit is down between the two routers, the output of the show l2vpn atom vc detail command shows the following status:


Device# show l2vpn atom vc detail 


.


.


.


Last remote LDP TLV    status rcvd: AC DOWN(rx,tx faults)





The debug messages also indicate that the attachment circuit is down, as shown in bold in the command output:


Device# debug l2vpn atom  vc event
Device# debug l2vpn atom  vc status event 
Device# debug l2vpn atom vc status fsm 
Device# debug l2vpn atom vc ldp




*Feb 26 11:51:42.427: AToM LDP [10.1.1.1]: Received notif msg, id 88
*Feb 26 11:51:42.427: AToM LDP [10.1.1.1]:   Status    0x00000007 [PW Status]
*Feb 26 11:51:42.427: AToM LDP [10.1.1.1]:   PW Status 0x00000006 [AC DOWN(rx,tx faults)]




Other pseudowire status messages include not-forwarding, pw-tx-fault, and pw-rx-fault. 






Message Codes in the Pseudowire Status Messages



The debug mpls l2transport vcand the show mpls l2transport vc detail commands show output that contains message codes. For example: 


    Label/status state machine: established, LruRru



    


AToM MGR [10.9.9.9, 100]: S:Evt local up, LndRru->LnuRru



    



The message codes (LruRru, LndRru, and LnuRru) indicate the status of the local and remote routers. You can use the following key to interpret the message codes:


  • 
L--local router
    

    • 

  • 
R--remote router
    

    • 

  • 
r or n--ready (r) or not ready (n)
    

    • 

  • 
u or d--up (u) or down (d) status
    

    • 




The output also includes other values:


  • 
D--Dataplane 
    

    • 

  • 
S--Local shutdown
    

    • 







Message Codes in the Pseudowire Status Messages using the commands associated with the L2VPN Protocol-Based CLIs feature



The debug l2vpn atom vc and the show l2vpn atom vc detail commands show output that contains message codes. For example: 


    Label/status state machine: established, LruRru



    


AToM MGR [10.9.9.9, 100]: S:Evt local up, LndRru->LnuRru



    



The message codes (LruRru, LndRru, and LnuRru) indicate the status of the local and remote routers. You can use the following key to interpret the message codes:



L—local router



R—remote router



r or n—ready (r) or not ready (n)



u or d—up (u) or down (d) status



The output also includes other values:



D—Dataplane 



S—Local shutdown








How to Configure MPLS Pseudowire Status Signaling




Enabling MPLS Pseudowire Status Signaling


 
		
 Perform the following task to enable the router to send pseudowire status to a peer router even when the attachment circuit is down. If both routers do not support pseudowire status messages, then disable the messages with the 
		  no 
			 status command. 
		

 
	 

SUMMARY STEPS
    1.   
       
			  
				enable 
			  
		  
    

    2.   
       
			  
				configure 
			  
			  
				terminal 
			  
		  
    

    3.   
       
			  
				pseudowire-class 
			  
			  
				name 
			  
		  
    

    4.   
       
			  
				status 
			  
		  
    

    5.   
       
			  
				encapsulation 
				mpls 
			  
		  
    

    6.   
       
			  
				exit 
			  
		  
    

    7.   
       
			  
				exit 
			  
		  
    

    8.   
       
			  
				show 
				mpls 
				l2transport 
				vc 
				detail 
			  
		  
    


DETAILED STEPS
     Command or ActionPurpose
    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 
			  
				pseudowire-class 
			  
			  
				name 
			  
		  
     

    Example:
     
			 
    Router(config)# pseudowire-class atom 
    
 
		  
    
 
          		  
			 
     Establishes a pseudowire class with a name that you specify and enters pseudowire class configuration mode. 
			 
    
 
		   
      
    

    Step 4 
			  
				status 
			  
		  
     

    Example:
     
			 
    Router(config-pw)# status 
    
 
		  
    
 
          		  
			 
     (Optional) Enables the router to send pseudowire status messages to the peer router through label advertisement and label notification messages.
			 
    
 
			 
    Note   
                
              
     By default, status messages are enabled. This step is included only in case status messages have been disabled. 
			 
    

    
 
			 
     If you need to disable status messages because both peer routers do not support this functionality, enter the 
				no 
				  statuscommand. 
			 
    
 
		   
      
    

    Step 5 
			  
				encapsulation 
				mpls 
			  
		  
     

    Example:
     
			 
    Router(config-pw)# encapsulation mpls
    
 
		  
    
 
          		  
			 
     Specifies the tunneling encapsulation. 
			 
    
 
		   
      
    

    Step 6 
			  
				exit 
			  
		  
     

    Example:
     
			 
    Router(config-pw)# exit
    
 
		  
    
 
          		  
			 
     Exits pseudowire class configuration mode.
			 
    
 
		   
      
    

    Step 7 
			  
				exit 
			  
		  
     

    Example:
     
			 
    Router(config)# exit
    
 
		  
    
 
          		  
			 
     Exits global configuration mode.
			 
    
 
		   
      
    

    Step 8 
			  
				show 
				mpls 
				l2transport 
				vc 
				detail 
			  
		  
     

    Example:
     
			 
    Router# show mpls l2transport vc detail 
    
 
		  
    
 
          		  
			 
     Validates that pseudowire messages can be sent and received. 
			 
    
 
		   
      
    

    

    

    

    Enabling MPLS Pseudowire Status Signaling using the commands associated with the L2VPN Protocol-Based CLIs feature
    

     
		
     Perform this task to enable the router to send pseudowire status to a peer router even when the attachment circuit is down. If both routers do not support pseudowire status messages, then disable the messages with the 
		  no 
			 status command. 
		
    
 
	 
    
SUMMARY STEPS
      1.   
       
			  
				enable 
			  
		  
      

      2.   
       
			  
				configure 
			  
			  
				terminal 
			  
		  
      

      3.   
       
			  
				interface pseudowire 
			  
				number 
			  
		  
      

      4.   
       
			  
				status 
			  
		  
      

      5.   
       
			  
				encapsulation 
				mpls 
			  
		  
      

      6.   
       
			  
				neighbor 
		   
				peer-address   
				vcid-value
      

      7.   
       
			  
				exit 
			  
		  
      

      8.   
       
			  
				exit 
			  
		  
      

      9.   
       
			  
				show 
				l2vpn 
				atom 
				vc 
				detail 
			  
		  
      


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 
			  
				enable 
			  
		  
       

      Example:
       
			 
      Router> enable
      
 
		  
      
 
            		  
			 
       Enables privileged EXEC mode. 
			 
      
 
			 
      •  Enter your password if prompted.
				
        

        • 

      
 
		   
      
      

      Step 2 
			  
				configure 
			  
			  
				terminal 
			  
		  
       

      Example:
       
			 
      Device# configure terminal
      
 
		  
      
 
            		  
			 
       Enters global configuration mode.
			 
      
 
		   
      
      

      Step 3 
			  
				interface pseudowire 
			  
				number 
			  
		  
       

      Example:
       
			 
      Device(config)# interface pseudowire 1 
      
 
		  
      
 
            		  
			 
       Establishes an interface pseudowire with a value that you specify and enters pseudowire configuration mode. 
			 
      
 
		   
      
      

      Step 4 
			  
				status 
			  
		  
       

      Example:
       
			 
      Device(config-pw)# status 
      
 
		  
      
 
            		  
			 
       (Optional) Enables the router to send pseudowire status messages to the peer router through label advertisement and label notification messages.
			 
      
 
			 
      Note   
                
              
       By default, status messages are enabled. This step is included only in case status messages have been disabled. 
			 
      

      
 
			 
       If you need to disable status messages because both peer routers do not support this functionality, enter the 
				no 
				  statuscommand. 
			 
      
 
		   
      
      

      Step 5 
			  
				encapsulation 
				mpls 
			  
		  
       

      Example:
       
			 
      Device(config-pw)# encapsulation mpls
      
 
		  
      
 
            		  
			 
       Specifies the tunneling encapsulation. 
			 
      
 
		   
      
      

      Step 6 
			  
				neighbor 
		   
				peer-address   
				vcid-value
       

      Example:
       
			 
      Device(config-pw)#  neighbor 10.0.0.1 123
      
 
		  
      
 
            		  
			 
       Specifies the peer IP address and virtual circuit (VC) ID value of a Layer 2 VPN (L2VPN) pseudowire. 
			 
      
 
		   
      
      

      Step 7 
			  
				exit 
			  
		  
       

      Example:
       
			 
      Device(config-pw)# exit
      
 
		  
      
 
            		  
			 
       Exits pseudowire class configuration mode.
			 
      
 
		   
      
      

      Step 8 
			  
				exit 
			  
		  
       

      Example:
       
			 
      Device(config)# exit
      
 
		  
      
 
            		  
			 
       Exits global configuration mode.
			 
      
 
		   
      
      

      Step 9 
			  
				show 
				l2vpn 
				atom 
				vc 
				detail 
			  
		  
       

      Example:
       
			 
      Device# show l2vpn atom vc detail 
      
 
		  
      
 
            		  
			 
       Validates that pseudowire messages can be sent and received. 
			 
      
 
		   
      
      

      

      

      

      

      Configuration Examples for MPLS Pseudowire Status Signaling
      

       
	 
      

      

      Example MPLS Pseudowire Status Signaling
      

       
		
       The following example configures the MPLS Pseudowire Status Signaling feature on two PE routers. By default, status messages are enabled. The 
		  status command is included in this example in case status messages have been disabled. 
		
      
 
	 
      

      PE1
       
		 
		
      interface Loopback0
 ip address 10.1.1.1 255.255.255.255
!
pseudowire-class atomstatus
 encapsulation mpls
 status
!
interface GigabitEthernet0/0/1
 xconnect 10.1.1.2 123 pw-class atomstatus
      
 
	 
      

      PE2
       
		 
		
      interface Loopback0
 ip address 10.1.1.2 255.255.255.255
!
pseudowire-class atomstatus
 encapsulation mpls
 status
!
interface GigabitEthernet3/3/0
 xconnect 10.1.1.1 123 pw-class atomstatus
      
 
	 
      

      

      

      Example MPLS Pseudowire Status Signaling using the commands associated with the L2VPN Protocol-Based CLIs feature
      

       
		
       The following example configures the MPLS Pseudowire Status Signaling feature on two PE routers. By default, status messages are enabled. The 
		  status command is included in this example in case status messages have been disabled. 
		
      
 
	 
      

      PE1
       
		 
		
      interface Loopback0
 ip address 10.1.1.1 255.255.255.255
!
template type pseudowire atomstatus
 encapsulation mpls
 status
!
interface pseudowire 100
 source template type pseudowire atomstatus
interface GigabitEthernet0/0/1
	service instance 300 ethernet
l2vpn xconnect context con1
 member GigabitEthernet2/1/1 service-instance 300
 member Pseudowire 100
      
 
	 
      

      PE2
       
		 
		
      interface Loopback0
 ip address 10.1.1.2 255.255.255.255
!
template type pseudowire atomstatus
 encapsulation mpls
 status
!
interface Pseudowire 100
 source template type pseudowire atomstatus
interface GigabitEthernet3/3/0
	service instance 300 ethernet
l2vpn xconnect context con1
 member GigabitEthernet2/1/1 service-instance 300
 member Pseudowire 100
      
 
	 
      

      

      

      Example  Verifying That Both Routers Support Pseudowire Status Messages
      

      
      
      
You can issue the show mpls l2transport vc detail command to show that both the local and remote routers support pseudowire status messages. The following example shows the line of output to look for: 
      

      
      Router# show mpls l2transport vc detail 
      

      
      .
      

      
      .
      

      
      .
      

      
      status TLV support (local/remote): enabled/supported
      

      
      

    
      

      

      

      Example  Verifying That Both Routers Support Pseudowire Status Messages using the commands associated with the L2VPN Protocol-Based CLIs feature
      

      
      
      
You can issue the show l2vpn atom vc detail command to show that both the local and remote routers support pseudowire status messages. The following example shows the line of output to look for: 
      

      
      Device# show l2vpn atom vc detail 
      

      
      .
      

      
      .
      

      
      .
      

      
      status TLV support (local/remote): enabled/supported
      

      
    
      

      

      

      

      Additional References
      

       
	 
      

      Related Documents
       
		 
		

       
					 
       Related Topic
					 
      
 
				        		
 
					 
       Document Title
					 
      
 
				        		

      
      

       
					 
       Cisco IOS commands
					 
      
 
				        		
 
					 
       
						Cisco IOS Master Commands List, All Releases 
					 
      
 
				        		

      

       
					 
       Description of commands associated with MPLS and MPLS applications
					 
      
 
				        		
 
					 
       
						Cisco IOS Multiprotocol Label Switching Command Reference 
					 
      
 
				        		

      

       
					 
       Any Transport over MPLS 
					 
      
 
				        		
 
					 
       Any Transport over MPLS 
					 
      
 
				        		

      
      

      

      
 
	 
      

      Standards
       
		 
		

       
					 
       Standard
					 
      
 
				        		
 
					 
       Title
					 
      
 
				        		

      
      

       
					 
       draft-ietf-pwe3-control-protocol-15.txt
					 
      
 
				        		
 
					 
       Pseudowire Setup and Maintenance Using LDP
					 
      
 
				        		

      

       
					 
       draft-ietf-pwe3-iana-allocation-08.txt
					 
      
 
				        		
 
					 
       IANA Allocations for Pseudo Wire Edge to Edge Emulation (PWE3)
					 
      
 
				        		

      

       
					 
       draft-martini-pwe3-pw-switching-03.txt
					 
      
 
				        		
 
					 
       Pseudo Wire Switching
					 
      
 
				        		

      
      

      

      
 
	 
      

      MIBs
       
		 
		

       
					 
       MIB
					 
      
 
				        		
 
					 
       MIBs Link
					 
      
 
				        		

      
      

       
					 
       Pseudowire Emulation Edge-to-Edge MIBs for Ethernet, Frame Relay, and ATM Services
					 
      
 
				        		
 
					 
       To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL:
					 
      
 
					 
       
						http:/​/​www.cisco.com/​go/​mibs 
					 
      
 
				        		

      
      

      

      
 
	 
      

      RFCs
       
		 
		

       
					 
       RFC
					 
      
 
				        		
 
					 
       Title
					 
      
 
				        		

      
      

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

      
      

      

      
 
	 
      

      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
      

      
			
      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 MPLS Pseudowire Status Signaling
       
				  
       Feature Name 
				  
      
 
				      		
 
				  
       Releases 
				  
      
 
				      		
 
				  
       Feature Information 
				  
      
 
				      		

      
      

       
				  
       MPLS Pseudowire Status Signaling 
				  
      
 
				      		
 
				  
       Cisco IOS XE Release 2.3 
				  
      
 
				      		
 
				  
       The MPLS Pseudowire Status Signaling feature enables you to configure the router so it can send pseudowire status to a peer router, even when the attachment circuit is down. 
				  
      
 
				  
       The following commands were introduced or modified: 
					 debug 
						mpls 
						l2transport 
						vc, 
					 show 
						mpls 
						l2transport 
						vc, 
					 status (pseudowire class).