This section provides an example to configure PW port based capture SAP that is used in ESM. For more information about PXC Based PW ports, see the 7450 ESS, 7750 SR, 7950 XRS, and VSR Layer 2 Services and EVPN Guide.
PXC Configuration
The following is a PXC configuration example:
configure
port-xc
pxc 1 create
port 1/1/1
no shutdown
pxc 2 create
port 2/1/1
no shutdown
With this configuration, ports 1/1/1 and 2/1/1 are auto-provisioned in hybrid mode operating as individual loopback ports. The SR OS system automatically creates a pair of sub-ports per PXC. Those sub-ports are, by default, are in the shutdown state, and must be explicitly enabled (no shutdown) by the operator.
configure
port pxc-1.a
shutdown
port pxc-1.b
shutdown
port pxc-2.a
shutdown
port pxc-2.a
shutdown
For redundancy purposes or increased bandwidth, the PXC sub-ports are aggregated in a LAG:
configure
lag 1 create
port pxc-1.a
port pxc-2.a
lag 2 create
port pxc-1.b
port pxc-2.b
FPE Configuration
A PW port is associated with PXC by an FPE configuration. FPE configuration facilitates creation of an internal tunnel over PXC. This tunnel is used to map the external PW to the PW port. For more information about FPE, see 7450 ESS, 7750 SR, 7950 XRS, and VSR Interface Configuration Guide.
The following is an FPE configuration example:
configure
fwd-path-ext
fpe 1 create
path xc-a lag-1 xc-b lag-2
pw-port
The association between xc-a/b (cross-connects) and LAG IDs is performed arbitrarily by the operator. For example, it can associate xc-a with lag-id 2 (which includes PXC sub-ports on the .b side) and xc-b with lag-id 1 (which includes PXC sub-ports on the .a side). However, the FPE always assigns the .a side of the pxc sub-ports to the transit side of the cross-connect, while the .b side of the pxc subport is assigned to the termination side of the cross-connect. See the PXC Based PW port sections in the 7450 ESS, 7750 SR, 7950 XRS, and VSR Layer 2 Services and EVPN Guide, for further information about transit/termination side of the cross-connect.
PW port creation
The PW port must be explicitly created in the SR OS, before mapping between PW and PW port can be performed.
pw-port 100 create
encap-type qinq
SDP creation for the external PW
The following displays an SDP configuration for the external PW.
configure
service
sdp 1 create
signaling tldp
far-end 10.1.1.1
The PW can be static or dynamically signaled, with MPLS or GRE transport.
Mapping between the external PW and the PW port
The stitching of the external PW and PW port is configured through an Epipe in vc-switching mode.
configure
service
epipe 10 customer 1 vc-switching create
spoke-sdp 1:100 create
pw-port 100 fpe 1
Capture PW-SAP creation
PW-SAPs can be configured as capture SAPs. In this example, a capture PW-SAP with s-tag 3 is created on the pw-port 100.
configure
service vpls 2 create
sap pw-port-100:3.* capture-sap create
From here, ESM functionality is applied to the PW-SAP in the same manner as on any other regular SAP.
Cross-connecting SAPs to PW ports
In addition to PW termination, a PW port can become a terminating point for a regular SAP. For example:
configure
service
epipe 10 customer 1 vc-switching create
sap 1/1/1:10.* create
pw-port 100 fpe 1
In this example, the outer VLAN tag 10 in the payload is removed on ingress and the payload is delivered to the PW port where it can be mapped to a capture PW-SAP. This scenario allows traffic distribution from a single I/O port to different EMS termination points (anchor line cards) based on outer VLANs.