- Title
- 3800x3600xscgTOC
- Preface
- Overview
- Using the Command-Line Interface
- Assigning the Switch IP Address and Default Gateway
- Configuring Cisco IOS Configuration Engine
- Administering the Switch
- Configuring Synchronous Ethernet
- Configuring the Switch External Alarms
- Configuring SDM Templates
- Configuring Switch-Based Authentication
- Configuring Interfaces
- Configuring VLANs
- Configuring Ethernet Virtual Connections (EVCs)
- Configuring Command Macros
- Configuring STP
- Configuring MSTP
- Configuring Optional Spanning-Tree Features
- Configuring Resilient Ethernet Protocol
- Configuring DHCP Features
- Configuring Dynamic ARP Inspection
- Configuring IGMP Snooping
- Configuring PIM Snooping
- Configuring IEEE 802.1x Port-Based Authentication
- Configuring IEEE 802.1ad
- Configuring Traffic Control
- Configuring CDP
- Configuring LLDP and LLDP-MED
- Configuring UDLD
- Configuring System Message Logging
- Configuring RMON
- Using the SD Flash Memory Module
- Configuring SNMP
- Configuring Embedded Event Manager
- Configuring Network Security with ACLs
- Configuring IPv6 ACLs
- Configuring Quality of Service (QoS)
- Hierarchical Color-Aware Policing
- Configuring Multi-level Priority Queues
- Configuring Policy-Based Routing (PBR)
- Configuring Control Plane Policing (CoPP)
- Configuring EtherChannels
- Configuring IP Unicast Routing
- Configuring IPv6 Unicast Routing
- Configuring IPv6 VPN over MPLS
- Configuring Virtual Router Redundancy Protocol
- Configuring HSRP
- Configuring Cisco IOS IP SLAs Operations
- Configuring Enhanced Object Tracking
- Configuring Ethernet OAM, CFM, and E-LMI
- Configuring Y.1731 Performance Monitoring
- Configuring Ethernet Data Plane Loopback
- L2VPN Protocol-Based CLIs
- Configuring IP Multicast Routing
- Configuring Multicast VPN
- Configuring MPLS, MPLS VPN, MPLS OAM, and EoMPLS
- Multiprotocol Label Switching Load Balancing
- MPLS Traffic Engineering Bundled Interface Support
- Configuring OSPF TTL Security Check
- Configuring Switched Port Analyzer (SPAN)
- Configuring Ethernet Ring Protection
- Auto-IP
- Troubleshooting
- Configuring Online Diagnostics
- Supported MIBs
- Working with the Cisco IOS File System, Configuration Files, and Software Images
- Configuring MPLS Transport Profile
- Unsupported Commands
- Index
Cisco ME 3800x and ME 3600x Switches Software Configuration Guide, Cisco IOS Release 15.4(2)S
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- Updated:
- April 7, 2021
Chapter: Configuring Ethernet Data Plane Loopback
Configuring Ethernet Data Plane Loopback
The Ethernet Data Plane Loopback feature provides a means for remotely testing the throughput of an Ethernet port. You can verify the maximum rate of frame transmission with no frame loss. This feature allows for bidirectional or unidirectional throughput measurement, and on-demand/out-of-service (intrusive) operation during service turn-up.
Limitations and Configuration Guidelines
The following limitations and configuration guidelines apply when configuring Ethernet Data Plane Loopback on the Cisco ME 3600X and ME 3800X:
- The switch does not support data plane loopback on routed port infrastructure.
- The switch does not support Etype, src-mac, or llc-oui based loopback traffic filtering.
- In external loopback on service instances, the ingress qos on the service instance will be bypassed but not the port level qos. Similarly, the egress port shaper cannot be bypassed.
- In internal loopback, the expected sequence is ingress qos, egress qos (egress port), but the ingress port shaper will also take effect.
- The switch cannot bypass the port shaper on the ingress port in both external and internal loopback.
- The switch supports one active session per EFP, per port.
- Internal session on the switchport is not supported.
- Internal session is supported only of EFPs (service instances, Ethernet flow points, EVCs).
- While configuring internal sessions on EFPs, dot1q tags are mandatory. Therefore, internal loopback is not supported on a range of dot1q tags. However, loopback sessions can be configured using dot1q/QinQ, even if the underlying EFP has the dot1q/QinQ range configured.
- Multiple external loopback sessions can be configured on the same EFP or switchport (VLAN).
- Enabling Ethernet loopback command in an untagged service instance is accepted at the service instance level but you cannot start the Ethernet loopback globally since dot1q filter is mandatory.
- Enabling or running Ethernet loopback in encapsulation default service instance is supported for tagged frames only when you give a specific dot1q filter value in the Ethernet loopback start command. The restriction is only for untagged traffic but you cannot start Ethernet Data Plane Loopback for untagged traffic as the dot1q filter is mandatory.
- Enabling Ethernet loopback command at interface level for both internal and external does not prompt any message for unsupported configurations.
- At one time, only one terminal loopback session can be active on an EFP.
- Egress span on the port and internal loopback on an EFP on the same port cannot be configured at the same time.
- The switch has only 1 Gigabit of bandwidth reserved for internal loopback. All internal sessions traffic has to be within this limit. There is an additional 18 bytes of overhead per packet in the internal loopback path.
Configuring Ethernet Data Plane Loopback
To enable and start Ethernet Data Plane Loopback on an interface, perform the following steps:
Note
By default the Session would be running for 300 seconds unless explicitly specified by the user and automatically stopped after the session time expiry.
To stop an active session on an interface or to stop all sessions use the ethernet loopback stop command.
Displaying Ethernet Dataplane Loopback Information
To verify the configuration on the switch use the show ethernet loopback command.
Sample Configurations
The example below enables and starts loopback, vlan 100 on the switchport trunk interface gigabitethernet 0/1 for external loopback.
Note Note: By default the Session would be running for 300 seconds unless explicitly specified by the user and automatically stopped after the session time expiry.
This example shows the default behavior of ethernet data plane loopback. The VLAN keyword is not specified, therefore packets with all VLAN tags and untagged packets will be loopbacked:
This example shows data plane loopback on a switch port. In this example, the packets tagged with VLAN 2 coming from the wire on ethernet 1/0 will be loopbacked:
In this example, packets tagged with VLAN 3/4/5 coming from the wire on ethernet1/0 will be loopbacked:
In this example, packets tagged with VLAN 3/4/5 coming from the relay on ethernet1/0 will be loopbacked:
In this example, untagged packets from the wire on ethernet 1/0 will be loopbacked:
In this example, external loopback for VLAN 100 on the switch port trunk GigabitEthernet 0/1 is enabled:
In this example, internal loopback for EFP 100 on GigabitEthernet 0/5 is enabled:
In this example, both internal and external loopback for EFP 100 on GigabitEthernet 0/5 is enabled:
In this example, internal loopback is started on an EFP:
In these examples, external loopback is started on an EFP:
In this example, external loopback is started on a switchport trunk VLAN:
In this example, all active sessions on the switch are displayed:
The following example displays the loopback capabilities per interface:
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