- Index
- Preface
- Product Overview
- Virtual Switching Systems (VSS)
- Layer 2 LAN Port Configuration
- Flex Links
- EtherChannels
- IEEE 802.1ak MVRP and MRP
- VLAN Trunking Protocol (VTP)
- VLANs
- Private VLANs (PVLANs)
- Private Hosts
- IEEE 802.1Q Tunneling
- Layer 2 Protocol Tunneling
- Spanning Tree Protocols (STP, MST)
- Optional STP Features
- IP Unicast Layer 3 Switching
- Multiprotocol Label Switching (MPLS)
- MPLS VPN Support
- Ethernet over MPLS (EoMPLS)
- Virtual Private LAN Services (VPLS)
- Ethernet Virtual Connections (EVC)
- Layer 2 over Multipoint GRE (L2omGRE)
- IPv4 Multicast Layer 3 Features
- IPv4 Multicast IGMP Snooping
- IPv4 PIM Snooping
- IPv4 Multicast VLAN Registration (MVR)
- IPv4 IGMP Filtering
- IPv4 Router Guard
- IPv4 Multicast VPN Support
- IPv6 Multicast Layer 3 Features
- IPv6 MLD Snooping
- NetFlow Hardware Support
- Call Home
- System Event Archive (SEA)
- Backplane Platform Monitoring
- Local SPAN, RSPAN, and ERSPAN
- SNMP IfIndex Persistence
- Top-N Reports
- Layer 2 Traceroute Utility
- Mini Protocol Analyzer
- PFC QoS Overview
- PFC QoS Guidelines and Restrictions
- PFC QoS Classification, Marking, and Policing
- PFC QoS Policy Based Queueing
- PFC QoS Global and Interface Options
- AutoQoS
- MPLS QoS
- PFC QoS Statistics Data Export
- Cisco IOS ACL Support
- Cisco TrustSec (CTS)
- AutoSecure
- MAC Address-Based Traffic Blocking
- Port ACLs (PACLs)
- VLAN ACLs (VACLs)
- Policy-Based Forwarding (PBF)
- Denial of Service (DoS) Protection
- Control Plane Policing (CoPP)
- Dynamic Host Configuration Protocol (DHCP) Snooping
- IP Source Guard
- Dynamic ARP Inspection (DAI)
- Traffic Storm Control
- Unknown Unicast and Multicast Flood Control
- IEEE 802.1X Port-Based Authentication
- Configuring Web-Based Authentication
- Port Security
- Lawful Intercept
- Online Diagnostic Tests
- Migrating From a 12.2SX QoS Configuration
Ethernet over MPLS (EoMPLS)
- Prerequisites for EoMPLS
- Restrictions for EoMPLS
- Information About EoMPLS
- Default Settings for EoMPLS
- How to Configure EoMPLS
Note ● For complete syntax and usage information for the commands used in this chapter, see these publications:
http://www.cisco.com/en/US/products/ps11845/prod_command_reference_list.html
- Cisco IOS Release 15.0SY supports only Ethernet interfaces. Cisco IOS Release 15.0SY does not support any WAN features or commands.
http://www.cisco.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.html
Participate in the Technical Documentation Ideas forum
Prerequisites for EoMPLS
Before you configure EoMPLS, ensure that the network is configured as follows:
Restrictions for EoMPLS
- EoMPLS in Cisco IOS Release 15.0SY does not support load balancing at the tunnel ingress; only one Interior Gateway Protocol (IGP) path is selected even if multiple IGP paths are available, but load balancing is available at the MPLS core.
- Ensure that the maximum transmission unit (MTU) of all intermediate links between endpoints is sufficient to carry the largest Layer 2 packet received.
- EoMPLS supports VLAN packets that conform to the IEEE 802.1Q standard. The 802.1Q specification establishes a standard method for inserting VLAN membership information into Ethernet frames.
- When the QoS is enabled on a Layer 2 port, either 802.1q P bits or IP precedence bits can be preserved with the trusted configuration. However, by default the unpreserved bits are overwritten by the value of preserved bits. For instance, if you preserve the P bits, the IP precedence bits are overwritten with the value of the P bits. To preserve the IP precedence bits, use the no platform qos rewrite ip dscp command. The no platform qos rewrite ip dscp command is not compatible with the MPLS and MPLS VPN features.
- EoMPLS is not supported with private VLANs.
- The following restrictions apply to using trunks with EoMPLS:
– To support Ethernet spanning tree bridge protocol data units (BPDUs) across an EoMPLS cloud, you must disable spanning tree for the Ethernet-over-MPLS VLAN. This ensures that the EoMPLS VLANs are carried only on the trunk to the customer switch. Otherwise, the BPDUs are not directed to the EoMPLS cloud.
– The native VLAN of a trunk must not be configured as an EoMPLS VLAN.
- In Cisco IOS Release 15.0SY, all protocols (for example, CDP, VTP, BPDUs) are tunneled across the MPLS cloud without conditions.
- Unique VLANs are required across interfaces. You cannot use the same VLAN ID on different interfaces.
- EoMPLS tunnel destination route in the routing table and the CEF table must be a /32 address (host address where the mask is 255.255.255.255) to ensure that there is a label-switched path (LSP) from PE to PE.
- For a particular EoMPLS connection, both the ingress EoMPLS interface on the ingress PE and the egress EoMPLS interface on the egress PE have to be subinterfaces with dot1Q encapsulation or neither is a subinterface.
- 802.1Q in 802.1Q over EoMPLS is supported if the outgoing interface connecting to MPLS network is a port on an Layer 2 card.
- Shaping EoMPLS traffic is not supported if the egress interface connecting to an MPLS network is a Layer 2 LAN port (a mode known as PFC-based EoMPLS).
- EoMPLS based on a PFC does not perform any Layer 2 lookup to determine if the destination MAC address resides on the local or remote segment and does not perform any Layer 2 address learning (as traditional LAN bridging does).
- The AToM control word is not supported.
- Ethernet packets with hardware-level cyclic redundancy check (CRC) errors, framing errors, and runt packets are discarded on input.
- You must configure VLAN-based EoMPLS on subinterfaces.
- Port-based EoMPLS and VLAN-based EoMPLS are mutually exclusive. If you enable a main interface for port-to-port transport, you also cannot enter commands on a subinterface.
- EoMPLS is not supported on Layer 3 VLAN interfaces.
- Point-to-point EoMPLS works with a physical interface and subinterfaces.
Information About EoMPLS
AToM Overview
Any Transport over MPLS (AToM) transports Layer 2 packets over an MPLS backbone. AToM uses a directed Label Distribution Protocol (LDP) session between edge routers for setting up and maintaining connections. Forwarding occurs through the use of two level labels that provide switching between the edge routers. The external label (tunnel label) routes the packet over the MPLS backbone to the egress PE at the ingress PE. The VC label is a demuxing label that determines the connection at the tunnel endpoint (the particular egress interface on the egress PE as well as the VLAN identifier for an Ethernet frame).
EoMPLS Overview
EoMPLS is one of the AToM transport types. EoMPLS works by encapsulating Ethernet PDUs in MPLS packets and forwarding them across the MPLS network. Each PDU is transported as a single packet. Cisco IOS Release 15.0SY supports two EoMPLS modes:
- VLAN mode—Transports Ethernet traffic from a source 802.1Q VLAN to a destination 802.1Q VLAN through a single VC over an MPLS network. VLAN mode uses VC type 5 as default (no dot1q tag) and VC type 4 (transport dot1 tag) if the remote PE does not support VC type 5 for subinterface (VLAN) based EoMPLS.
- Port mode—Allows all traffic on a port to share a single VC across an MPLS network. Port mode uses VC type 5.
Note For both VLAN mode and port mode, EoMPLS in Cisco IOS Release 15.0SY does not allow local switching of packets between interfaces unless you use loopback interfaces.
LAN ports can receive Layer 2 traffic, impose labels, and switch the frames into the MPLS core.
Default Settings for EoMPLS
How to Configure EoMPLS
Configuring VLAN-Based EoMPLS
To configure VLAN-based EoMPLS, perform this task on the provider edge (PE) routers:
This is a VLAN-based EoMPLS configuration sample:
Note The IP address is configured on subinterfaces of the CE devices.
To verify and display the configuration of Layer 2 VLAN transport over MPLS tunnels, perform the following:
- To display a single line for each VLAN, naming the VLAN, status, and ports, enter the show vlan brief command.
- To verify that the PE router endpoints have discovered each other, enter the show mpls ldp discovery command. When an PE router receives an LDP hello message from another PE router, it considers that router and the specified label space to be “discovered.”
- To verify that the label distribution session has been established, enter the show mpls ldp neighbor command. The third line of the output shows that the state of the LDP session is operational and shows that messages are being sent and received.
- To verify that the label forwarding table is built correctly, enter the show mpls forwarding-table command to verify that a label has been learned for the remote PE and that the label is going from the correct interface to the correct next-hop.
The output shows the following data:
– Local tag—Label assigned by this router.
– Outgoing tag or VC—Label assigned by next hop.
– Prefix or Tunnel Id—Address or tunnel to which packets with this label are going.
– Bytes tag switched— Number of bytes switched out with this incoming label.
– Outgoing interface—Interface through which packets with this label are sent.
– Next Hop—IP address of neighbor that assigned the outgoing label.
To display detailed information about each VC, add the keyword detail.
Configuring Port-Based EoMPLS
To support 802.1Q-in-802.1Q traffic and Ethernet traffic over EoMPLS in Cisco IOS Release 15.0SY, configure port-based EoMPLS by performing this task:
The following is an example of a port-based configuration:
To verify and display the configuration of Layer 2 VLAN transport over MPLS tunnels, perform the following:
- To display a single line for each VLAN, naming the VLAN, status, and ports, enter the show vlan brief command.
- To verify that the PE router endpoints have discovered each other, enter the show mpls ldp discovery command. When an PE router receives an LDP Hello message from another PE router, it considers that router and the specified label space to be “discovered.”
- To verify that the label distribution session has been established, enter the show mpls ldp neighbor command. The third line of the output shows that the state of the LDP session is operational and shows that messages are being sent and received.
- To verify that the label forwarding table is built correctly, enter the show mpls forwarding-table command.
– Local tag—Label assigned by this router.
– Outgoing tag or VC—Label assigned by next hop.
– Prefix or Tunnel Id—Address or tunnel to which packets with this label are going.
– Bytes tag switched— Number of bytes switched out with this incoming label.
– Outgoing interface—Interface through which packets with this label are sent.
– Next Hop—IP address of neighbor that assigned the outgoing label.
http://www.cisco.com/en/US/products/hw/switches/ps708/tsd_products_support_series_home.html
Participate in the Technical Documentation Ideas forum