Juniper JUNOSE 11.1.X MULTICAST ROUTING, Configuration Manual

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Each high-density Ethernet module has eight physical ports, numbered 0–7. A logical
port is available for the hardware multicast packet replication feature, numbered
port 8.
JUNOSe tracks the OIFs in an mroute that have been redirected to use the hardware
multicast packet replication hardware. The system accepts only egress multicast
traffic to traverse the interface stack on the enabled port. The system drops unicast
traffic that is routed to this port.
Each port on the I/O module or IOA displayed in Figure 5 on page 19 has two queues.
These queues are further down the egress path than the queues found on the line
module and populated by the FC.
The low-priority queue is dedicated to packets that are received from the line module
queues that are dedicated to the physical ports. This queue blocks when full and
provides backpressure to the line module. This queue services unicast and multicast
traffic that is not using the hardware multicast packet replication feature.
The high-priority queue is dedicated to packets that are received from the line module
queue for port 8. This queue is serviced at a higher priority than the first queue, and
drops packets when full.
For more information about high-density Ethernet, see Configuring Ethernet Interfaces
in the JUNOSe Physical Layer Configuration Guide .
Supported Modules and Encapsulations
You can enable hardware multicast packet replication on port 8 of the following
high-density Ethernet modules:
■
GE-8 I/O module (pairs with the GE-HDE line module)
■
ES2-S1 GE-8 IOA (pairs with the ES2 4G LM and the ES2 10G LM)
When enabled, the hardware multicast packet replication feature defines the
encapsulation of the egress multicast packet. The following encapsulations are
supported:
■
IPv4 over Gigabit Ethernet
■
IPv4 over VLAN
■
IPv4 over S-VLAN
NOTE: 802.3ad link aggregation group (LAG) bundles do not support hardware
multicast packet replication.
The hardware multicast packet replication feature also provides an interface over
which you can configure the following:
■
IP MTU
■
Ethernet MTU
20 ■
Configuring Hardware Multicast Packet Replication
JUNOSe 11.1.x Multicast Routing Configuration Guide