Riverstone Networks WICT1-12 - Manual (Page 374)

17-66 Riverstone Networks RS Switch Router User Guide Release 8.0
Configuring L2 Tunnels MPLS Configuration
Note The MTU size for MPLS ports must be at least 22 bytes more than the MTU size
of incoming non-MPLS traffic; additional bytes are required for multiple labels.
The default maximum transmission unit (MTU) size for non-MPLS ports on the
RS is 1522 bytes. The default MTU size for ports on MPLS-enabled line cards on
the RS is 1568 bytes, which allows for multiple MPLS labels).
The MPLS network must be configured with an MTU that is large enough to
transport the maximum size frame that will be transported in the tunnel LSP (this
can be at least 12 bytes more than the largest frame size). If an MPLS packet
exceeds the tunnel MTU, it will be dropped. If an egress LSR receives a packet
that exceeds the MTU of the destination L2 interface, the packet will be dropped.
FEC-Label Bindings
On the RS, the following can be used to identify the FEC-to-label binding for a virtual circuit:
• VLAN ID assigned to a customer by a service provider
• incoming port
• incoming port and the customer-specific VLAN ID assigned by the customer
This section includes example configurations for each type of FEC-to-label binding.
Ingress and Egress LSR Configuration for L2 Dynamic Labels
On the ingress and egress LSRs, configure the following:
1. Configure the L2 FEC.
- If you are using the VLAN ID as the FEC, create the VLAN with the
vlan create
and
vlan
add ports
commands.
- If you are using the incoming port as the FEC, use the
ldp map ports
command to map the
port to a logical customer ID number.
Note The ports that are mapped to a single customer ID number must be either all trunk
ports or all access ports.
A port cannot be mapped to more than one customer ID number.
- If you are using a combination of customer VLAN ID and incoming port as the FEC, create the
VLAN with the
vlan create
and
vlan add ports
commands and use the
ldp map ports
command to map the port to a logical customer ID number.
2. Advertise the FEC-to-label mapping via LDP to the remote peers. Enable and start LDP.
- Specify the remote LDP peer with the
ldp add remote-peer
command. Specify the router
ID of the remote LDP peer, which must be one of the loopback addresses of the remote router.