Alcatel-Lucent 7750 SR OS Service Manual page 634

VPLS Service Configuration Commands
mode is used for VPLS interfaces participating in IGMP snooping and is represented by an IP
multicast [s,g] record.
vpls
Syntax vpls vpls-service-id mda card/slot
vpls vpls-service-id mda card/slot [igmp-record group ip-address {source ip-address |
starg}]
Context show>egress-replication
Description
The vpls vpls-service-id mda slot/mda command displays the flooding list used by the Layer 2
flooding mode for the VPLS service on the specified MDA. The Layer 2 flooding list is limited to
SAPs, spoke-SDP and mesh-SDP bindings that exist on the egress forwarding complex serviced by
the specified MDA. For the 10G IOM, two MDAs share the same egress forwarding plane. In this
case the Layer 2 flooding list will contain destinations for both MDAs (if entries exist). The only
VPLS interfaces that will not be included in the list are residential SAPs because Layer 2 replication
is not permitted to a residential SAP. A packet processed by the egress Layer 2 flooding list may not
be replicated to each destination. A packet will not be replicated to an interface on the Layer 2
flooding list because of the following:
The ingress interface is the same as egress interface (source squelching rule)
Destination SAPs in the list may be displayed in a chain context representing common replication
behavior. All SAPs in a single chain are processed a single time through the egress forwarding plane.
If a discard decision is made for the first SAP in the chain, no replication processing is done for any of
the chain members. If the forwarding plane decides to replicate the first SAP in the chain, it will
replicate to all SAPs in the chain.
The vpls vpls-service-id mda card/slot igmp-record grp-address {source source-ip-address | starg}
command displays the IGMP record based flooding list for the vpls-service-id on the specified MDA.
Unlike the Layer 2 flooding list for the VPLS context, an IGMP record list may contain interfaces
from other VPLS contexts due to MVR (Multicast VPLS Registration) events on the individual VPLS
interfaces. VPLS interfaces in other VPLS contexts become associated with the specified vpls-
service-id based on the MVR from-vpls definition. Another difference between the VPLS Layer 2
flooding list and IGMP lists is that many IGMP lists may exist (each associated with a different [s,g]
record) and the lists may contain residential SAPs. The SAP chaining and replication behavior is
similar to the VPLS Layer 2 flooding list.
IP multicast packets ingressing the vpls-service-id must match either a [*,g] or [s,g] record to be
associated with the record's egress IP multicast IGMP flooding list. A [*,g] record will match any
ingress IP multicast packet destined to the class D destination IP address represented by "g". An [s,g]
record will match any ingress IP multicast packet with a source IP address matching "s" and a
destination IP address matching "g". In the case that a packet could match both a [*,g] and [s,g]
record, the [s,g] record takes precedence. Each [*,g] and [s,g] record has its own IGMP flooding list.
The list will only appear on an egress forwarding plane (MDA) when a member of the list (VPLS
interface) exists on the forwarding plane.
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• The ingress interface split horizon group is the same as the egress interface (residential bridging
rule)
• The egress interface is down or blocking
• The packet matches a discard event while processing that destination interface
• An egress MTU violation occurs for the destination interface
7750 SR OS Services Guide