Juniper JUNOS OS 10.4 - FOR EX REV 1 Manual page 1685

Copyright © 2010, Juniper Networks, Inc.
This example uses MVRP to dynamically create VLANs on the switching network. You
can disable dynamic VLAN creation and create VLANs statically, if desired. Enabling
MVRP on the trunk interface of each switch in your switching network ensures that the
active VLAN information for the switches in the network is propagated to each switch
through the trunk interfaces, assuming dynamic VLAN creation is enabled for MVRP.
MVRP ensures that the VLAN membership information on the trunk interface is updated
as the switch's access interfaces become active or inactive in the configured VLANs in a
static or dynamic VLAN creation setup.
You do not need to explicitly bind a VLAN to the trunk interface. When MVRP is enabled,
the trunk interface advertises all the VLANs that are active (bound to access interfaces)
on that switch. An MVRP-enabled trunk interface does not advertise VLANs that have
been configured on the switch but that are not currently bound to an access interface.
Thus, MVRP provides the benefit of reducing network overhead—by limiting the scope
of broadcast, unknown unicast, and multicast (BUM) traffic to interested devices only.
When VLAN access interfaces become active or inactive, MVRP ensures that the updated
information is advertised on the trunk interface. Thus, in this example, distribution Switch
C does not forward traffic to inactive VLANs.
This example shows a network with three VLANs:
Access Switch A has been configured to support all three VLANS and all three VLANS
are active, bound to interfaces that are connected to personal computers:
—Connects PC1 as a member of
ge-0/0/1
ge-0/0/2 —Connects PC2 as a member of
—Connects PC3 as a member of
ge-0/0/3
Access Switch B has also been configured to support three VLANS. However, currently
only two VLANs are active, bound to interfaces that are connected to personal computers:
ge-0/0/0 —Connects PC4 as a member of
—Connects PC5 as a member of
ge-0/0/1
Distribution Switch C learns the VLANs dynamically using MVRP through the connection
to the access switches. Distribution Switch C has two trunk interfaces:
xe-0/1/1 —Connects the switch to access Switch A.
—Connects the switch to access Switch B.
xe-0/1/0
Figure 42 on page 1582 shows MVRP configured on two access switches and one distribution
switch.
Chapter 64: Examples: Bridging and VLAN Configuration
, , and
finance sales
, VLAN ID 100
finance
lab , VLAN ID 200
, VLAN ID 300
sales
finance , VLAN ID 100
, VLAN ID 200
lab
.
lab
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