BGP-AD VPWS or BGP Auto Discovery Virtual Private Wire Service is a way for a PE router to automatically discover other PE routers that are providing L2VPN services but to just one other PE and not 2 or more.
CSR1
interface GigabitEthernet3
service instance 100 ethernet
encapsulation dot1q 100
!
l2vpn vfi context VPWS
vpn id 100
autodiscovery bgp signaling ldp
!
bridge-domain 100
member GigabitEthernet3 service-instance 100
member vfi VPWS
!
router bgp 100
!
address-family l2vpn vpls
neighbor 192.0.2.3 activate
neighbor 192.0.2.9 activate
neighbor 192.0.2.9 prefix-length-size 2
exit-address-family
CSR5
interface GigabitEthernet3
service instance 100 ethernet
encapsulation dot1q 100
!
l2vpn vfi context VPWS
vpn id 100
autodiscovery bgp signaling ldp
!
bridge-domain 100
member GigabitEthernet3 service-instance 100
member vfi VPWS
!
router bgp 100
!
address-family l2vpn vpls
neighbor 192.0.2.3 activate
neighbor 192.0.2.9 activate
neighbor 192.0.2.9 prefix-length-size 2
exit-address-family
CSR3
router bgp 100
neighbor IBGP peer-group
neighbor IBGP remote-as 100
neighbor IBGP update-source Loopback0
neighbor 192.0.2.1 peer-group IBGP
neighbor 192.0.2.5 peer-group IBGP
!
address-family l2vpn vpls
neighbor IBGP route-reflector-client
neighbor 192.0.2.1 activate
neighbor 192.0.2.5 activate
XR9
router bgp 100
address-family l2vpn vpls-vpws
!
neighbor 192.0.2.1
remote-as 100
update-source Loopback0
!
address-family l2vpn vpls-vpws
route-reflector-client
Signalling bgp disable
!
neighbor 192.0.2.5
remote-as 100
update-source Loopback0
!
address-family l2vpn vpls-vpws
route-reflector-client
Signalling bgp disable
CSR1#show xconnect all
Legend: XC ST=Xconnect State S1=Segment1 State S2=Segment2 State
UP=Up DN=Down AD=Admin Down IA=Inactive
SB=Standby HS=Hot Standby RV=Recovering NH=No Hardware
XC ST Segment 1 S1 Segment 2 S2
------+---------------------------------+--+---------------------------------+--
UP pri vfi VPWS UP mpls 192.0.2.5:100 UP
CSR1#show bridge-domain 100
Bridge-domain 100 (2 ports in all)
State: UP Mac learning: Enabled
Aging-Timer: 300 second(s)
GigabitEthernet3 service instance 100
vfi VPWS neighbor 192.0.2.5 100
AED MAC address Policy Tag Age Pseudoport
0 5000.0011.0001 forward dynamic 298 GigabitEthernet3.EFP100
0 5000.0012.0002 forward dynamic 300 VPWS.1004045
CSR5#show xconnect all
Legend: XC ST=Xconnect State S1=Segment1 State S2=Segment2 State
UP=Up DN=Down AD=Admin Down IA=Inactive
SB=Standby HS=Hot Standby RV=Recovering NH=No Hardware
XC ST Segment 1 S1 Segment 2 S2
------+---------------------------------+--+---------------------------------+--
UP pri vfi VPWS UP mpls 192.0.2.1:100 UP
CSR5#show bridge-domain 100
Bridge-domain 100 (2 ports in all)
State: UP Mac learning: Enabled
Aging-Timer: 300 second(s)
GigabitEthernet3 service instance 100
vfi VPWS neighbor 192.0.2.1 100
AED MAC address Policy Tag Age Pseudoport
0 5000.0011.0001 forward dynamic 298 VPWS.100401b
0 5000.0012.0002 forward dynamic 298 GigabitEthernet3.EFP100
IOS17
interface GigabitEthernet0/1.100
encapsulation dot1Q 100
ip address 10.100.100.17 255.255.255.0
!
router eigrp 100
network 10.100.100.0 0.0.0.255
IOS18
interface GigabitEthernet0/2.100
encapsulation dot1Q 100
ip address 10.100.100.18 255.255.255.0
!
router eigrp 100
network 10.100.100.0 0.0.0.255
IOS18#sh ip eigrp 100 neighbors
EIGRP-IPv4 Neighbors for AS(100)
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.100.100.17 Gi0/2.100 14 5d21h 91 819 0 12
CSR1
interface GigabitEthernet3
service instance 100 ethernet
encapsulation dot1q 100
!
l2vpn vfi context VPWS
vpn id 100
autodiscovery bgp signaling ldp
!
bridge-domain 100
member GigabitEthernet3 service-instance 100
member vfi VPWS
!
router bgp 100
!
address-family l2vpn vpls
neighbor 192.0.2.3 activate
neighbor 192.0.2.9 activate
neighbor 192.0.2.9 prefix-length-size 2
exit-address-family
CSR5
interface GigabitEthernet3
service instance 100 ethernet
encapsulation dot1q 100
!
l2vpn vfi context VPWS
vpn id 100
autodiscovery bgp signaling ldp
!
bridge-domain 100
member GigabitEthernet3 service-instance 100
member vfi VPWS
!
router bgp 100
!
address-family l2vpn vpls
neighbor 192.0.2.3 activate
neighbor 192.0.2.9 activate
neighbor 192.0.2.9 prefix-length-size 2
exit-address-family
CSR3
router bgp 100
neighbor IBGP peer-group
neighbor IBGP remote-as 100
neighbor IBGP update-source Loopback0
neighbor 192.0.2.1 peer-group IBGP
neighbor 192.0.2.5 peer-group IBGP
!
address-family l2vpn vpls
neighbor IBGP route-reflector-client
neighbor 192.0.2.1 activate
neighbor 192.0.2.5 activate
XR9
router bgp 100
address-family l2vpn vpls-vpws
!
neighbor 192.0.2.1
remote-as 100
update-source Loopback0
!
address-family l2vpn vpls-vpws
route-reflector-client
Signalling bgp disable
!
neighbor 192.0.2.5
remote-as 100
update-source Loopback0
!
address-family l2vpn vpls-vpws
route-reflector-client
Signalling bgp disable
CSR1#show xconnect all
Legend: XC ST=Xconnect State S1=Segment1 State S2=Segment2 State
UP=Up DN=Down AD=Admin Down IA=Inactive
SB=Standby HS=Hot Standby RV=Recovering NH=No Hardware
XC ST Segment 1 S1 Segment 2 S2
------+---------------------------------+--+---------------------------------+--
UP pri vfi VPWS UP mpls 192.0.2.5:100 UP
CSR1#show bridge-domain 100
Bridge-domain 100 (2 ports in all)
State: UP Mac learning: Enabled
Aging-Timer: 300 second(s)
GigabitEthernet3 service instance 100
vfi VPWS neighbor 192.0.2.5 100
AED MAC address Policy Tag Age Pseudoport
0 5000.0011.0001 forward dynamic 298 GigabitEthernet3.EFP100
0 5000.0012.0002 forward dynamic 300 VPWS.1004045
CSR5#show xconnect all
Legend: XC ST=Xconnect State S1=Segment1 State S2=Segment2 State
UP=Up DN=Down AD=Admin Down IA=Inactive
SB=Standby HS=Hot Standby RV=Recovering NH=No Hardware
XC ST Segment 1 S1 Segment 2 S2
------+---------------------------------+--+---------------------------------+--
UP pri vfi VPWS UP mpls 192.0.2.1:100 UP
CSR5#show bridge-domain 100
Bridge-domain 100 (2 ports in all)
State: UP Mac learning: Enabled
Aging-Timer: 300 second(s)
GigabitEthernet3 service instance 100
vfi VPWS neighbor 192.0.2.1 100
AED MAC address Policy Tag Age Pseudoport
0 5000.0011.0001 forward dynamic 298 VPWS.100401b
0 5000.0012.0002 forward dynamic 298 GigabitEthernet3.EFP100
IOS17
interface GigabitEthernet0/1.100
encapsulation dot1Q 100
ip address 10.100.100.17 255.255.255.0
!
router eigrp 100
network 10.100.100.0 0.0.0.255
IOS18
interface GigabitEthernet0/2.100
encapsulation dot1Q 100
ip address 10.100.100.18 255.255.255.0
!
router eigrp 100
network 10.100.100.0 0.0.0.255
IOS18#sh ip eigrp 100 neighbors
EIGRP-IPv4 Neighbors for AS(100)
H Address Interface Hold Uptime SRTT RTO Q Seq
(sec) (ms) Cnt Num
0 10.100.100.17 Gi0/2.100 14 5d21h 91 819 0 12