The Trunk EFP Support feature provides support for Ethernet flow points (EFPs) on trunk ports. A trunk port allows a range of VLANs to be forwarded on a given interface while still maintaining data-plane segmentation between the VLANs.
Your software release
may not support all the features documented in this module. For the latest
caveats and feature information, see
Bug Search Tool and the
release notes for your platform and software release. To find information about
the features documented in this module, and to see a list of the releases in
which each feature is supported, see the feature information table.
Use Cisco Feature
Navigator to find information about platform support and Cisco software image
support. To access Cisco Feature Navigator, go to
An account on Cisco.com is not required.
Restrictions for Trunk EFP Support
rewrite ingress tag pop 1 symmetric command is the only
rewrite command that is supported for trunk EFP configurations. The
rewrite ingress tag pop 1 symmetric command must be included in the configuration when the Trunk EFP Support feature is enabled.
A bridge-domain number that is part of a trunk EFP configuration cannot be shared by other EFPs under the same port or interface.
Only one trunk EFP can be configured under one port or interface.
All features configured on a trunk EFP (other than encapsulations and bridge-domain assignments) are applied uniformly to all VLANs and bridge domains. If a feature requires VLAN-specific or bridge-domain-specific configuration values, the feature cannot be applied on the trunk EFP. Those special VLANs or bridge domains must be removed from the EFP trunk to form individual EFPs.
The Carrier Ethernet infrastructure supports the following types of Ethernet flow points (EFPs):
Static EFPs that are user-configurable.
Dynamic EFPs that are created and maintained during a Cisco Intelligent Services Gateway ( ISG) session.
With this feature, a new EFP type has been added that is intended for use on a trunk port.
A trunk port allows a range of VLANs to be forwarded on a given interface while maintaining data-plane segmentation between the VLANs.
Trunk EFP (with or without port channel) supports encapsulation of up to 1000 VLANs.
Like a static EFP, this new type of EFP is user-configurable via the
service instance trunk command, the
encapsulation command, and the
bridge-domain from-encapsulation command when the Trunk EFP Support feature is enabled.
Ethernet Flow Points
An Ethernet flow
point (EFP) is a forwarding decision point in the provider edge (PE) router,
which gives network designers flexibility to make many Layer 2 flow decisions
within the interface. Many EFPs can be configured on a single physical port.
(The number varies from one device to another.) EFPs are the logical
demarcation points of an Ethernet virtual connection (EVC) on an interface. An
EVC that uses two or more user network interfaces (UNIs) requires an EFP on the
associated ingress and egress interfaces of every device that the EVC passes
EFPs can be
configured on any Layer 2 traffic port; however, they are usually configured on
UNI ports. The following parameters (matching criteria) can be configured on
Frames of a
specific VLAN, a VLAN range, or a list of VLANs (100-150 or 100,103,110)
Frames with no
identical double-tags (VLAN tags) as specified
identical Class of Service (CoS) values
A frame passes each
configured match criterion until the correct matching point is found. If a
frame does not fit any of the matching criteria, it is dropped. Default
criteria can be configured to avoid dropping frames.
The following types
of commands can be used in an EFP:
commands—In each EFP, VLAN tag management can be specified with the following
Pop—1) pops out a tag; 2)
pops out two tags
Push—1) pushes in a tag; 2)
pushes in two tags
Translate—1 to 1) changes a
tag value; 1 to 2) pops one tag and pushes two tags; 2 to 1) pops two tags and
pushes one tag; 2 to 2) changes the value for two tags
commands—Each EFP specifies the forwarding command for the frames that enter
the EFP. Only one forwarding command can be configured per EFP. The forwarding
options are as follows:
Layer 2 point-to-point
forwarding to a pseudowire tunnel
Multipoint bridge forwarding
to a bridge domain entity
forwarding between two different interfaces
commands—In each EFP, the QoS features or parameters can be changed and the ACL
can be updated.
An Ethernet interface can be configured as a trunk port (interface). A trunk port, also known as a trunk, is a point-to-point link between a networking device and another networking device. Trunks carry the traffic of multiple VLANs over a single link and allow you to extend VLANs across an entire network. A trunk port configured on the interface with two or more VLANs can carry traffic for several VLANs simultaneously.
To correctly deliver the traffic on a trunk port with several VLANs, the device uses the IEEE 802.1Q encapsulation or tagging method.
In the following example, EFP support has been configured on a trunk interface.
Device# configure terminal
Device(config)# interface gigabitethernet2/0/1
Device(config-if)# service instance trunk 1 ethernet
Device(config-if-srv)# encapsulation dot1q 1 - 5, 7, 9 - 12
Device(config-if-srv)# rewrite ingress tag pop 1 symmetric
Device(config-if-srv)# bridge-domain from-encapsulation
Device(config-if-srv)# no shutdown
Example: Verifying the Trunk EFP Support Configuration
The following is sample output from the
show ethernet service instance command. The output displays trunk as the service instance type and indicates that a bridge domain for VLANs in the range of 12 to 1900 (as specified by the encapsulation parameters) has been created for service instance 4000 on a trunk port (interface).
Device# show ethernet service instance id 4000 interface gigabitethernet0/0/5 detail
Service Instance ID: 4000
Service Instance Type: Trunk
Associated Interface: GigabitEthernet0/0/5
Encapsulation: dot1q 12-1900 vlan protocol type 0x8100
Rewrite: ingress tag pop 1 symmetric
Interface Dot1q Tunnel Ethertype: 0x8100
Pkts In Bytes In Pkts Out Bytes Out
168729725 10798985220 160246675 10255787200
Microblock type: Bridge-domain
Configuring Ethernet Connectivity Fault Management in a Service Provider Network
The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to
www.cisco.com/go/cfn. An account on Cisco.com is not required.
Table 1 Feature Information for Trunk EFP Support
Trunk EFP Support
Cisco IOS XE Release 3.5S
This feature provides support for Ethernet Flow Points (EFPs) on trunk ports (interfaces).
In Cisco IOS XE Release 3.5S, support was added for the Cisco ASR 903 Router.
The following commands were introduced or modified:
encapsulation dot1q (service instance),rewrite ingress tag,service instance ethernet,
show ethernet service instance, and
show ethernet service interface.