Y.1731 and CFM Over EVPN-ELINE Multi-home
Overview
The Multi Home EVPN ELINE Y.1731 CFM over Sub-interface feature enables the monitoring and management of Ethernet Virtual Private Network (EVPN) E-Line services using the Y.1731 Connectivity Fault Management (CFM) protocol over sub-interfaces. This feature enhances fault detection and performance monitoring capabilities for EVPN E-Line services, allowing network operators to ensure high availability and reliability of their networks. By extending Y.1731 CFM functionality to sub-interfaces in multi home EVPN E-Line deployments, this feature provides comprehensive end-to-end visibility and control, enabling proactive fault detection, isolation, and troubleshooting.
CFM multi-homing allows Customer Edge (CE) device to connect more than one Provider Edge (PE) device. Multi-homing ensures redundant connectivity. The redundant PE device ensures that there is no traffic disruption when there is a network failure.
Feature Characteristics
•	Utilizes sub-interfaces to partition Ethernet traffic within the Multi home EVPN ELINE architecture, enabling efficient service delivery and management.
•	Implements EVPN ELINE architecture with multi-homing capabilities, facilitating the creation of Ethernet Virtual Private Networks with simplified configurations and reduced complexity.
•	Provides robust fault detection mechanisms to identify connectivity issues, link failures, and service disruptions in Ethernet networks.
Benefits
•	Provides detailed insights into Ethernet service performance, enabling proactive monitoring and optimization of network resources.
•	Minimizes service downtime by promptly detecting and resolving faults, ensuring uninterrupted service delivery and customer satisfaction.
•	Optimizes network resource utilization and bandwidth allocation by identifying and addressing connectivity issues in a timely manner.
•	Facilitates rapid fault identification and isolation, accelerating troubleshooting processes and reducing mean time to repair (MTTR).
Ensures compliance with Service Level Agreements (SLAs) by maintaining service quality metrics within defined thresholds and objectives.
Configuration
Configure Multi Home EVPN ELINE Y.1731 CFM over Sub-interface for enhanced fault management in EVPN networks.
Topology
The following topology consists of customer edge routers CE1 and CE2 with IPv2 Provider Edge routers PE1 and PE2. These are interconnected through the core router P in the IPv4 MPLS provider networks.
 EVPN ELINE Over CFM Sub-interface
The following sessions displays the detailed information about configurations, and validations for CFM over sub-interface.
1.	Configure Loopback Interface on PE1.
PE1(#configure terminal 
PE1(config)#interface lo 
PE1(config-if)#ip address 1.1.1.1/32
PE1(config-if)#exit 
PE1(config-if)#commit
2.	Configure Global LDP for distributing MPLS labels in the network.
  PE1(config)# router ldp
  PE1(config-router)# router-id 1.1.1.1
  PE1(config-router)# targeted-peer ipv4 7.7.7.7
  PE1(config-router)# targeted-peer ipv4 8.8.8.8
  PE1(config-router-targeted-peer)#exit
  PE1(config-router)# exit
  PE1(config)# commit
3.	Enable EVPN over MPLS and set a global VTEP IP.
PE1(config)# evpn mpls enable
PE1(config)# commit
PE1(config)# evpn mpls vtep-ip-global 1.1.1.1
PE1(config)# commit
4.	Configure the interfaces connecting to the network, enabling LDP and MPLS label switching.
PE1(config)# interface xe6
PE1(config-if)# ip address 10.1.0.1/16
PE1(config-if)# enable-ldp ipv4
PE1(config-if)# label-switching
PE1(config-if)# exit
PE1(config)# commit
5.	Set up OSPF for IP routing within the network. 
PE1(config)# router ospf 1
PE1(config-router)# ospf router-id 1.1.1.1
PE1(config-router)# network 1.1.1.1/32 area 0
PE1(config-router)# network 10.1.0.0/16 area 0
PE1(config-router)# exit
PE1(config)# commit
6.	Set up BGP for EVPN to exchange MAC and IP information.
PE1(config)# router bgp 1
PE1(config-router)# neighbor 7.7.7.7 remote-as 1
PE1(config-router)# neighbor 7.7.7.7 update-source lo
PE1(config-router)# neighbor 8.8.8.8 remote-as 1
PE1(config-router)# neighbor 8.8.8.8 update-source lo
PE1(config-router)# address-family l2vpn evpn
PE1(config-router-af)# neighbor 7.7.7.7 activate
PE1(config-router-af)# neighbor 8.8.8.8 activate
PE1(config-router-af)# exit
PE1(config-router)# exit
PE1(config)# commit
7.	Configure MAC VRF.
PE1(config)# mac vrf vrf2
PE1(config-vrf)# rd 1.1.1.1:2
PE1(config-vrf)# route-target both 2:2
PE1(config-vrf)# exit
PE1(config)# commit
8.	Configure EVPN and map VRF.
PE1(config)# evpn mpls id 52 xconnect target-mpls-id 2
PE1(config-evpn-mpls)# host-reachability-protocol evpn-bgp vrf2
PE1(config)# commit
9.	Configure access port on interface xe33.2
PE1(config-if)# interface xe33.2 switchport
PE1(config-if)# description access-side-int
PE1(config-if)# encapsulation dot1q 2
PE1(config-if)# access-if-evpn
PE1(config-access-if)# map vpn-id 52
PE1(config-access-if)# exit
PE1(config)# commit
10.	Set up CFM to monitor connectivity within the network.
PE1(config)#hardware-profile filter cfm-domain- name-str enable
PE1(config)# ethernet cfm domain-type character-string domain-name 12346 level 7 mip-creation none
PE1(config-ether-cfm-mpls-md)# service ma-type string ma-name 124
PE1(config-ether-cfm-mpls-ma)# ethernet cfm mep up mpid 10 active true xe33.2 vlan 2
PE1(config-ether-cfm-mpls-ma-mep)#cc multicast state enable
PE1(config-ether-cfm-mpls-ma-mep)#exit-ether- ma-mep-mode
    PE1(config-ether-cfm-mpls-ma)#  rmep auto-discovery enable
PE1(config-ether-cfm-mpls-ma)#cc interval 10ms
PE1(config-ether-cfm-mpls-ma)#exit-ether-ma- mode
PE1(config-ether-cfm-mpls)#exit
PE1(config)#exit
PE1(config)#commit
Note:	Similarly follow the same steps to configure respective cfm mep up and other CFM features for PE2 and PE3.
Configuration Snapshot:
PE1:
!
interface lo
 ip address 1.1.1.1/32
!
router ldp
 router-id 1.1.1.1
 targeted-peer 7.7.7.7
 targeted-peer 8.8.8.8
!
router ospf 1
 router-id 1.1.1.1
 network  1.1.1.1/32 area 0
 network  10.1.0.0/16 area 0
!
router bgp 1
 bgp log-neighbor-changes
 neighbor 7.7.7.7 remote-as 1
 neighbor 7.7.7.7 update-source lo
 neighbor 8.8.8.8 remote-as 1
 neighbor 8.8.8.8 update-source lo
 !
 address-family l2vpn evpn
 neighbor 7.7.7.7 activate
 neighbor 8.8.8.8 activate
 exit-address-family
!
evpn mpls enable
evpn mpls vtep-ip-global 1.1.1.1
hardware-profile filter cfm-domain-name-str enable
hardware-profile statistics cfm-ccm enable
!
interface xe6
ip address 10.1.0.1/16
enable-ldp ipv4 
label-switching
!
vrf definition vrf2
 rd 1.1.1.1:2
 route-target both 2:2
!
evpn mpls id 52 xconnect target-mpls-id 2
 host-reachability-protocol evpn-bgp vrf2
!
interface xe33.2 swicthport
 description access-side-int
 encapsulation dot1q 2
 access-if-evpn
  map vpn-id 52
!
ethernet cfm domain-type character-string domain-name 12346 level 7 mip-creation none
 service ma-type string ma-name 124
  ethernet cfm mep up mpid 10 active true xe33.2 vlan 2
   cc multicast state enable
   exit-ether-ma- mode
   rmep auto-discovery enable
   cc interval 10ms
   exit-ether-ma- mode
!
P:
!
interface lo
 ip address 2.2.2.2/32 
!
interface xe6
ip address 10.1.0.2/16 
enable-ldp ipv4
label-switching
!
interface xe21
 ip address 123.1.1.1/24
 enable-ldp ipv4
label-switching
!
interface xe20
 ip address 124.1.1.1/24
 enable-ldp ipv4
label-switching
!
router ldp
 router-id 2.2.2.2
!
router ospf 1
 router-id 2.2.2.2
 network 2.2.2.2/32 area 0
 network 10.1.0.0/16 area 0
 network 123.1.1.0/24 area 0
 network 124.1.1.0/24 area 0
!
PE2:
!
interface lo
 ip address 7.7.7.7/32
!
interface xe21
 ip address 123.1.1.2/24
 enable-ldp ipv4 
label-switching 
!
router ldp
 router-id 7.7.7.7/32
 targeted-peer ipv4 1.1.1.1
 targeted-peer ipv4 8.8.8.8
!
router ospf 1
 router-id 7.7.7.7
 network  7.7.7.7/32 area 0
 network 123.1.1.0/24 area 0
!
router bgp 1
 bgp log-neighbor-changes
 neighbor 1.1.1.1 remote-as 1
 neighbor 1.1.1.1 update-source lo
 neighbor 8.8.8.8 remote-as 1
 neighbor 8.8.8.8 update-source lo
 address-family l2vpn evpn
 neighbor 1.1.1.1 activate
 neighbor 8.8.8.8 activate
 exit-address-family
!
evpn mpls enable
evpn mpls vtep-ip-global 7.7.7.7
hardware-profile filter evpn-mpls-mh enable
evpn mpls multihoming enable
!
vrf definition vrf2
 rd 7.7.7.7:2
 route-target both 2:2
!
interface Po1
 load-interval 30
 evpn multi-homed system-mac 0000.aaaa.bbbc
!
interface Po1.2 switchport
 encapsulation dot1q 2
 access-if-evpn
  map vpn-id 2
!
interface xe5
 channel-group 1 mode active
!
ethernet cfm domain-type character-string domain-name 12346 level 7 mip-creation none
 service ma-type string ma-name 124
  ethernet cfm mep up mpid 20 active true po1.2 vlan 2
   cc multicast state enable
    ethernet cfm loss-measurement reply slm
    ethernet cfm delay-measurement reply dmm
   exit-ether-ma- mode
   rmep auto-discovery enable
   cc interval 10ms
   exit-ether-ma- mode
!
PE3:
!
interface lo
 ip address 8.8.8.8/32
!
interface xe20
 ip address 124.1.1.2/24
 enable-ldp ipv4 
label-switching
!
interface xe4
 channel-group 1 mode active
!
router ldp
 router-id 8.8.8.8
 targeted-peer ipv4 1.1.1.1
 targeted-peer ipv4 7.7.7.7
!
router ospf 1
 router-id 8.8.8.8
 network  8.8.8.8/32 area 0
 network network 124.1.1.0/24 area 0
!
router bgp 1
 bgp log-neighbor-changes
 neighbor 1.1.1.1 remote-as 1
 neighbor 1.1.1.1 update-source lo
 neighbor 7.7.7.7 remote-as 1
 neighbor 7.7.7.7 update-source lo
 address-family l2vpn evpn
 neighbor 1.1.1.1 activate
 neighbor 7.7.7.7 activate
 exit-address-family
!
evpn mpls enable
evpn mpls vtep-ip-global 8.8.8.8
hardware-profile filter evpn-mpls-mh enable
evpn mpls multihoming enable
!
vrf definition vrf2
 rd 8.8.8.8:2
 route-target both 2:2
!
interface Po1
 load-interval 30
 evpn multi-homed system-mac 0000.aaaa.bbbc
!
interface Po1.2 switchport
 encapsulation dot1q 2
 access-if-evpn
  map vpn-id 2
!
ethernet cfm domain-type character-string domain-name 12346 level 7 mip-creation none
 service ma-type string ma-name 124
  ethernet cfm mep up mpid 30 active true po1.2 vlan 2
   cc multicast state enable
    ethernet cfm loss-measurement reply slm
    ethernet cfm delay-measurement reply dmm
   exit-ether-ma- mode
   rmep auto-discovery enable
   cc interval 10ms
   exit-ether-ma- mode
   !
Validation
The following are the validations for PE1 and PE2.
PE1 
The following validation is for PE1.
PE1#SH evpn mpls xconnect
EVPN Xconnect Info
========================
AC-AC: Local-Cross-connect
AC-NW: Cross-connect to Network
AC-UP: Access-port is up
AC-DN: Access-port is down
NW-UP: Network is up
NW-DN: Network is down
NW-SET: Network and AC both are up
 
 
 
Local                            Remote       Connection-Details
===================================================================================
VPN-ID       EVI-Name      MTU   VPN-ID       Source       Destination                   PE-IP           MTU   Type   NW-Status
===================================================================================
52           ----          1500  2            xe33.2       00:00:00:aa:aa:bb:bb:00:00:00 7.7.7.7         1500  AC-NW  NW-SET
                                                                                         8.8.8.8         1500  ----   ----
PE1#show ethernet cfm errors domain 12346
 
Domain Name         Level     MEPID     Defects
-----------------------------------------------
12346               7         20        .....
 
PE1#show ethernet cfm ma status domain 12346 ma-name 124
MA NAME                  STATUS
-------------------------------
    124                  Active
PE1#show ethernet cfm maintenance-points remote domain 12346 ma-name 124
 MEPID     RMEPID     LEVEL     Rx CCM    RDI    PEER-MAC        TYPE
----------------------------------------------------------------------
 10        20         7         Yes       False  00aa.bb00.0002 Learnt
 10        30         7         Yes       False  00aa.dd00.0003 Learnt
 
 
PE1#show ethernet cfm maintenance-points local mep domain 12346 ma-name 124
MPID Dir Lvl CC-Stat HW-Status  CC-Intvl MAC-Address    Def Port  MD Name
---------------------------------------------------------------------------
10   Up  7   Enable  Installed  100 ms   3417.ebe4.af22 F   xe33.2 12346
 
PE1#ping ethernet mac 00aa.bb00.0002 unicast source 10 domain 12346 ma 124
 success rate is  100 (5/5)
 
 
PE1#traceroute ethernet 00aa.bb00.0002 mepid 10 domain 12346 ma 124
MP Mac         Hops  Relay-action          Ingress/Egress  Ingress/Egress action
00aa.bb00.0002   1     RlyHit                Ingress         IngOK
 
PE1#ping ethernet mac 00aa.dd00.0003 unicast source 10 domain 12346 ma 124
 success rate is  100 (5/5)
PE1-7011#traceroute ethernet 00aa.dd00.0003 mepid 10 domain 12346 ma 124
MP Mac         Hops  Relay-action          Ingress/Egress  Ingress/Egress action
00aa.dd00.0003   1     RlyHit                Ingress         IngOK
Verify Delay Measurement:
PE1#delay-measurement type proactive profile-name DM rmep 20 mep 10 domain 12346 ma 124
PE1-7011#2019 Feb 14 10:34:53.935 : PE2-7033 : ONMD : INFO : [CFM_PM_SESSION_INFO_5]: CFM Frame Delay Measurement session started for MEP Id 10 and RMEP Id 20
 
PE1#show ethernet cfm delay-measurement mep 10 domain 12346 ma-name 124
 MD                     : 12346
 MA                     : 124
 MEP                    : 10
 VLAN ID                : 2
 Interface              : xe33.2
 Peer MAC Address       : 00aa.bb00.0002
 
CURRENT:
======================
 RMEP ID        : 20
 Measurement ID : 3
 Measurement Type            : DMM
 Elapsed time(sec)           : 16
 Start Time                  : 2019 Feb 14 10:36:53
 Suspect Flag                : FALSE
 Min Frame Delay(usec)       : 23
 Max Frame Delay(usec)       : 24
 Avg Frame Delay(usec)       : 23
 Min Inter FD Variation(usec): 0
 Max Inter FD Variation(usec): 1
 Avg Inter FD Variation(usec): 0
 
             FRAME DELAY BINS
 Bin Number    Bin Threshold(usec)          Bin Counter
========================================================
 1             0          - < 4999           16
 2             5000       - < 9999           0
 3             10000      - < 4294967295     0
 
           INTER-FRAME DELAY BINS
 Bin Number    Bin Threshold(usec)          Bin Counter
========================================================
 1             0          - < 4999           15
 2             5000       - < 4294967295     0
 
 
HISTORY STATISTICS
======================
 MD                     : 12346
 MA                     : 124
 MEP                    : 10
 VLAN ID                : 2
 Interface              : xe33.2
 RMEP ID        : 20
 Measurement ID              : 1
 Measurement Type            : DMM
 Elapsed time(sec)           : 60
 End Time                    : 2019 Feb 14 10:35:53
 Suspect Flag                : FALSE
 Min Frame Delay(usec)       : 23
 Max Frame Delay(usec)       : 24
 Avg Frame Delay(usec)       : 23
 Min Inter FD Variation(usec): 0
 Max Inter FD Variation(usec): 1
 Avg Inter FD Variation(usec): 0
 
             FRAME DELAY BINS
 Bin Number    Bin Threshold(usec)          Bin Counter
========================================================
 1             0          - < 4999           59
 2             5000       - < 9999           0
 3             10000      - < 4294967295     0
 
           INTER-FRAME DELAY BINS
 Bin Number    Bin Threshold(usec)          Bin Counter
========================================================
 1             0          - < 4999           58
 2             5000       - < 4294967295     0
 
 RMEP ID        : 20
 Measurement ID              : 2
 Measurement Type            : DMM
 Elapsed time(sec)           : 60
 End Time                    : 2019 Feb 14 10:36:53
 Suspect Flag                : FALSE
 Min Frame Delay(usec)       : 23
 Max Frame Delay(usec)       : 24
 Avg Frame Delay(usec)       : 23
 Min Inter FD Variation(usec): 0
 Max Inter FD Variation(usec): 1
 Avg Inter FD Variation(usec): 0
 
             FRAME DELAY BINS
 Bin Number    Bin Threshold(usec)          Bin Counter
========================================================
 1             0          - < 4999           60
 2             5000       - < 9999           0
 3             10000      - < 4294967295     0
 
           INTER-FRAME DELAY BINS
 Bin Number    Bin Threshold(usec)          Bin Counter
========================================================
 1             0          - < 4999           59
 2             5000       - < 4294967295     0
 
Verify Synthetic Loss Measurement:
PE1#loss-measurement type proactive profile-name SLM rmep 20 mep 10 domain 12346 ma 124
PE1#2019 Feb 14 10:35:17.758 : PE2-7011 : ONMD : INFO : [CFM_DEFECT_INFO_5]: CFM Frame Loss Measurement  started for MEP:10 MA:124 MD:12346
PE1-7011#show ethernet cfm loss-measurement mep 10 domain 12346 ma-name 124
MEP: 10 MA: 124
CURRENT:
 Measurement ID : 3
  Suspect                    : False
  Measurement Type           : slm
  Elapsed time(sec)          : 19
  Start Time                 : 2019 Feb 14 10:37:16
  Near End loss              : 0
  Far End loss               : 0
  Near End accumulated loss  : 0
  Far End accumulated loss   : 0
  Near End frame loss ratio  : 0
  Far End frame loss ratio   : 0
 
HISTORY:
 
 Measurement ID : 1
  Suspect                    : False
  Measurement Type           : slm
  Elapsed time(sec)          : 60
  End Time                   : 2019 Feb 14 10:36:16
  Near End loss              : 0
  Far End loss               : 0
  Near End accumulated loss  : 0
  Far End accumulated loss   : 0
  Near End frame loss ratio  : 0
  Far End frame loss ratio   : 0
  Near End frame loss ratio min  : 0
  Far End frame loss ratio min  : 0
  Near End frame loss ratio max  : 0
  Far End frame loss ratio max  : 0
 
 Measurement ID : 2
  Suspect                    : False
  Measurement Type           : slm
  Elapsed time(sec)          : 60
  End Time                   : 2019 Feb 14 10:37:16
  Near End loss              : 0
  Far End loss               : 0
  Near End accumulated loss  : 0
  Far End accumulated loss   : 0
  Near End frame loss ratio  : 0
  Far End frame loss ratio   : 0
  Near End frame loss ratio min  : 0
  Far End frame loss ratio min  : 0
  Near End frame loss ratio max  : 0
  Far End frame loss ratio max  : 0
PE2/PE3
The following validations for PE2 and PE3.
PE2#show evpn mpls xconnect
EVPN Xconnect Info
========================
AC-AC: Local-Cross-connect
AC-NW: Cross-connect to Network
AC-UP: Access-port is up
AC-DN: Access-port is down
NW-UP: Network is up
NW-DN: Network is down
NW-SET: Network and AC both are up
 
Local                            Remote       Connection-Details
================================ ============ ===================================================================================
VPN-ID       EVI-Name      MTU   VPN-ID       Source       Destination                   PE-IP           MTU   Type   NW-Status
===================================================================================
2            ----          1500  52           po1.2        --- Single Homed Port ---     1.1.1.1         1500  AC-NW  NW-SET
PE2#show ethernet cfm errors domain 12346
 
Domain Name         Level     MEPID     Defects
-----------------------------------------------
12346               7         20        .....
PE2#show ethernet cfm ma status domain 12346 ma-name 124
MA NAME                  STATUS
-------------------------------
    124                  Active
PE2#show ethernet cfm maintenance-points local mep domain 12346 ma-name 124
MPID Dir Lvl CC-Stat HW-Status  CC-Intvl MAC-Address    Def Port  MD Name
---------------------------------------------------------------------------
20   Up  7   Enable  Installed  100 ms   00aa.bb00.0002 F   po1.2 12346
PE2#show ethernet cfm maintenance-points remote domain 12346 ma-name 124
 MEPID     RMEPID     LEVEL     Rx CCM    RDI    PEER-MAC        TYPE
----------------------------------------------------------------------
 20        10         7         Yes       False  3417.ebe4.af22 Learnt
 
PE2#ping ethernet mac 3417.ebe4.af22 unicast source 10 domain 12346 ma 124
 success rate is  100 (5/5)
PE2#traceroute ethernet 3417.ebe4.af22 mepid 10 domain 12346 ma 124
 MP Mac         Hops  Relay-action          Ingress/Egress  Ingress/Egress action
3417.ebe4.af22   1     RlyHit                Ingress         IngOK