Technical Documentation

Restricting Broadcast Packets in VPLS

You can configure filters, policers, and broadcast and unknown filters to determine which kind of traffic is allowed into and out of a VPLS domain. You can apply these filters and policers to CE-facing interfaces only.

To restrict the flow of broadcast and unknown unicast packets into a VPLS domain, you must create a firewall filter and apply the filter to one of the forwarding tables of the VPLS routing instance. When you apply a filter in this way, the filter processes traffic from all interfaces in the instance, including vt interfaces. To configure match conditions for a VPLS-based firewall filter, include the source-mac-address, destination-mac-address, interface-group, ethernet-type, or vlan-ethernet-type statements at the [edit firewall family vpls filter filter-name term term-name from] hierarchy level. Then, specify statements to activate the desired action (for example, discard) for the matched packets at the [edit firewall family vpls filter filter-name term term-name then] hierarchy level.

To apply the filter to the broadcast and unknown unicast table of a VPLS routing instance, include the input statement and the name of the filter at the [edit routing-instances instance-name forwarding-options family vpls flood] hierarchy level. To apply the filter to the destination MAC address table of a VPLS routing instance, include the input statement and the name of the filter at the [edit routing-instances instance-name forwarding-options family vpls filter] hierarchy level.

[edit]firewall {family vpls {filter vpls-flood {term 1 {from {destination-mac-address (broadcast | multicast | unknown-unicast) {
# The broadcast, multicast,
# and unknown-unicast options apply to MX Series
# routers only.
00.90.69.dc.95.3b/48;}
}
then discard;}
term 2 {then accept;}}
}
}routing-instances {green {forwarding-options {family vpls {(flood | filter) {input vpls-flood;}}}}}

When you configure VPLS, a priority filter for Spanning Tree Protocol (STP) bridge protocol data units (BPDUs) is enabled by default. This BPDU filter matches on the well-known STP MAC address of 01:80:c2:00:00:00/24 and applies high priority to this traffic.

For more information on VPLS policers and filters, see the Junos Policy Framework Configuration Guide and the Junos VPNs Configuration Guide.

Related Topics


Published: 2010-07-20

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