HP 6125G User manual

HP 6125 Blade Switch Series
High Availability
Configuration Guide
Part number: 5998-3161
Software version: Release 2103
Document version: 6W100-20120907

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© Copyright 2012 Hewlett-Packard Development Company, L.P.
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The information contained herein is subject to change without notice.
HEWLETT-PACKARD COMPANY MAKES NO WARRANTY OF ANY KIND WITH REGARD TO THIS
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AND FITNESS FOR A PARTICULAR PURPOSE. Hewlett-Packard shall not be liable for errors contained
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herein.

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Contents
High availability overview··········································································································································· 1
Availability requirements··················································································································································1
Availability evaluation······················································································································································1
High availability technologies ·········································································································································2
Fault detection technologies ····································································································································2
Protection switchover technologies·························································································································3
Configuring Ethernet OAM ········································································································································· 5
Ethernet OAM overview···················································································································································5
Major functions of Ethernet OAM ··························································································································5
Ethernet OAMPDUs··················································································································································5
How Ethernet OAM works ······································································································································6
Standards and protocols ·········································································································································8
Ethernet OAM configuration task list ······························································································································8
Configuring basic Ethernet OAM functions····················································································································9
Configuring link monitoring ·············································································································································9
Configuring errored symbol event detection ·········································································································9
Configuring errored frame event detection ········································································································ 10
Configuring errored frame period event detection···························································································· 10
Configuring errored frame seconds event detection ························································································· 10
Configuring Ethernet OAM remote loopback············································································································· 10
Enabling Ethernet OAM remote loopback ········································································································· 10
Rejecting the Ethernet OAM remote loopback request from a remote port···················································· 12
Displaying and maintaining Ethernet OAM configuration ························································································ 12
Ethernet OAM configuration example ························································································································· 13
Configuring CFD ························································································································································15
Overview········································································································································································· 15
Basic CFD concepts··············································································································································· 15
CFD functions························································································································································· 17
Protocols and standards ······································································································································· 18
CFD configuration task list ············································································································································ 18
Configuring basic CFD settings ···································································································································· 19
Enabling CFD························································································································································· 19
Configuring the CFD protocol version················································································································· 19
Configuring service instances ······························································································································ 19
Configuring MEPs·················································································································································· 20
Configuring MIP generation rules························································································································ 21
Configuring CFD functions············································································································································ 21
Configuration prerequisites ·································································································································· 21
Configuring CC on MEPs ····································································································································· 21
Configuring LB on MEPs ······································································································································· 22
Configuring LT on MEPs········································································································································ 22
Displaying and maintaining CFD ································································································································· 23
CFD configuration example ·········································································································································· 24
Configuring DLDP·······················································································································································28
DLDP overview································································································································································ 28
Background···························································································································································· 28
How DLDP works ··················································································································································· 29

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DLDP configuration task list··········································································································································· 35
Configuring the duplex mode and speed of an Ethernet interface··········································································· 35
Enabling DLDP ································································································································································ 36
Setting DLDP mode························································································································································· 36
Setting the interval to send advertisement packets ····································································································· 36
Setting the delaydown timer ········································································································································· 37
Setting the port shutdown mode ··································································································································· 37
Configuring DLDP authentication·································································································································· 38
Resetting DLDP state······················································································································································· 38
Displaying and maintaining DLDP································································································································ 39
DLDP configuration examples ······································································································································· 39
Automatically shutting down unidirectional links······························································································· 39
Manually shutting down unidirectional links ······································································································ 43
Troubleshooting DLDP···················································································································································· 46
Configuring RRPP ·······················································································································································47
RRPP overview ································································································································································ 47
Background···························································································································································· 47
Basic concepts in RRPP ········································································································································· 47
RRPPDUS································································································································································· 49
RRPP timers····························································································································································· 50
How RRPP works···················································································································································· 50
Typical RRPP networking······································································································································· 52
Protocols and standards ······································································································································· 55
RRPP configuration task list············································································································································ 55
Creating an RRPP domain············································································································································· 56
Configuring control VLANs ··········································································································································· 56
Configuration guidelines ······································································································································ 56
Configuration procedure ······································································································································ 57
Configuring protected VLANs······································································································································· 57
Configuring RRPP rings·················································································································································· 58
Configuring RRPP ports ········································································································································· 58
Configuring RRPP nodes ······································································································································· 59
Activating an RRPP domain··········································································································································· 60
Configuring RRPP timers ················································································································································ 61
Configuring an RRPP ring group ·································································································································· 61
Configuration restrictions and guidelines ··········································································································· 61
Configuration procedure ······································································································································ 62
Displaying and maintaining RRPP ································································································································ 62
RRPP configuration examples········································································································································ 62
Single ring configuration example ······················································································································ 62
Intersecting ring configuration example·············································································································· 65
Dual homed rings configuration example ·········································································································· 70
Intersecting-ring load balancing configuration example··················································································· 80
Troubleshooting······························································································································································ 89
Configuring Smart Link ··············································································································································90
Smart Link overview ······················································································································································· 90
Background···························································································································································· 90
Terminology ··························································································································································· 91
How Smart Link works ·········································································································································· 92
Smart Link collaboration mechanisms ················································································································· 92
Smart Link configuration task list ·································································································································· 93
Configuring a Smart Link device ·································································································································· 93
Configuration prerequisites ·································································································································· 93

iii
Configuring protected VLANs for a smart link group························································································ 93
Configuring member ports for a smart link group ····························································································· 94
Configuring role preemption for a smart link group·························································································· 95
Enabling the sending of flush messages ············································································································· 95
Configuring an associated device ······························································································································· 96
Configuration prerequisites ·································································································································· 96
Enabling the receiving of flush messages ··········································································································· 96
Displaying and maintaining Smart Link ······················································································································· 96
Smart Link configuration examples ······························································································································ 97
Single smart link group configuration example ································································································· 97
Multiple smart link groups load sharing configuration example····································································101
Configuring Monitor Link········································································································································ 106
Monitor Link overview ·················································································································································106
Terminology ·························································································································································106
How Monitor Link works·····································································································································107
Configuring Monitor Link ············································································································································107
Configuration prerequisites ································································································································107
Creating a monitor link group ···························································································································107
Configuring monitor link group member ports·································································································107
Displaying and maintaining Monitor Link ·················································································································108
Monitor Link configuration example ··························································································································108
Configuring VRRP···················································································································································· 112
VRRP overview······························································································································································112
VRRP standard protocol mode ····································································································································113
Introduction to VRRP group·································································································································113
VRRP timers ··························································································································································114
Packet format ·······················································································································································115
Principles of VRRP················································································································································116
VRRP tracking·······················································································································································116
VRRP application (taking IPv4-based VRRP for example)················································································117
VRRP load balancing mode ········································································································································118
Overview······························································································································································118
Assigning virtual MAC addresses ·····················································································································119
Virtual forwarder ·················································································································································121
Packet types ·························································································································································123
Configuring VRRP for IPv4···········································································································································123
VRRP for IPv4 configuration task list ··················································································································123
Configuring a VRRP operation mode ················································································································124
Specifying the type of MAC addresses mapped to virtual IP addresses·······················································124
Creating a VRRP group and configuring virtual IP address············································································125
Configuring router priority, preemptive mode and tracking function ····························································126
Configuring VF tracking······································································································································127
Configuring VRRP packet attributes···················································································································128
Enabling the trap function for VRRP···················································································································129
Displaying and maintaining VRRP for IPv4·······································································································129
Configuring VRRP for IPv6···········································································································································130
VRRP for IPv6 configuration task list ··················································································································130
Specifying the type of MAC addresses mapped to virtual IPv6 addresses ··················································130
Creating a VRRP group and configuring a virtual IPv6 address ····································································131
Configuring router priority, preemptive mode and tracking function ····························································132
Configuring VF tracking······································································································································133
Configuring VRRP packet attributes···················································································································134
Displaying and maintaining VRRP for IPv6·······································································································135

iv
IPv4-based VRRP configuration examples ·················································································································135
Single VRRP group configuration example·······································································································135
VRRP interface tracking configuration example ·······························································································138
VRRP with multiple VLANs configuration example···························································································142
VRRP load balancing mode configuration example ························································································144
IPv6-based VRRP configuration examples ·················································································································154
Single VRRP group configuration example·······································································································154
VRRP interface tracking configuration example ·······························································································157
VRRP with multiple VLANs configuration example···························································································161
VRRP load balancing mode configuration example ························································································165
Troubleshooting VRRP··················································································································································174
The screen frequently displays error prompts. ·································································································174
Multiple masters are present in the same VRRP group.···················································································174
Frequent VRRP state transition.···························································································································174
Configuring BFD······················································································································································ 175
BFD overview································································································································································175
How BFD works ···················································································································································175
BFD packet format···············································································································································177
Supported features ··············································································································································179
Protocols and standards ·····································································································································179
Configuring BFD basic functions ································································································································179
Configuration prerequisites ································································································································179
Configuration procedure ····································································································································179
Displaying and maintaining BFD································································································································181
Configuring track ···················································································································································· 182
Track overview ·····························································································································································182
Introduction to collaboration ······························································································································182
Collaboration fundamentals·······························································································································182
Collaboration application example···················································································································183
Track configuration task list·········································································································································183
Associating the track module with a detection module ···························································································184
Associating track with NQA ······························································································································184
Associating track with BFD·································································································································184
Associating track with interface management ·································································································185
Associating the track module with an application module······················································································186
Associating track with VRRP·······························································································································186
Associating track with static routing··················································································································188
Displaying and maintaining track entries··················································································································189
Track configuration examples·····································································································································189
VRRP-track-NQA collaboration configuration example (the master monitors the uplink) ····························189
Configuring BFD for a VRRP backup to monitor the master············································································193
Configuring BFD for the VRRP master to monitor the uplinks··········································································196
Static routing-track-NQA collaboration configuration example ·····································································199
Static routing-Track-BFD collaboration configuration example·······································································204
VRRP-track-interface management collaboration configuration example (the master monitors the uplink
interface)·······························································································································································207
Support and other resources ·································································································································· 211
Contacting HP ······························································································································································211
Subscription service ············································································································································211
Related information······················································································································································211
Documents····························································································································································211
Websites·······························································································································································211
Conventions ··································································································································································212

v
Index ········································································································································································ 214

1
High availability overview
Communication interruptions can seriously affect widely-deployed value-added services such as IPTV
and video conference. Therefore, the basic network infrastructures must be able to provide high
availability.
The following are the effective ways to improve availability:
•Increasing fault tolerance
•Speeding up fault recovery
•Reducing impact of faults on services
Availability requirements
Availability requirements fall into three levels based on purpose and implementation.
Table 1 Availability requirements
Level Re
q
uirement Solution
1 Decrease system software and
hardware faults
•Hardware—Simplifying circuit design, enhancing
production techniques, and performing reliability tests.
•Software—Reliability design and test
2 Protect system functions from being
affected if faults occur
Device and link redundancy and deployment of switchover
strategies
3 Enable the system to recover as fast
as possible
Performing fault detection, diagnosis, isolation, and
recovery technologies
The level 1 availability requirement should be considered during the design and production process of
network devices. Level 2 should be considered during network design. Level 3 should be considered
during network deployment, according to the network infrastructure and service characteristics.
Availability evaluation
Mean Time Between Failures (MTBF) and Mean Time to Repair (MTTR) are used to evaluate the
availability of a network.
MTBF
MTBF is the predicted elapsed time between inherent failures of a system during operation. It is typically
in the unit of hours. A higher MTBF means a high availability.
MTTR
MTTR is the average time required to repair a failed system. MTTR in a broad sense also involves spare
parts management and customer services.
MTTR = fault detection time + hardware replacement time + system initialization time + link recovery time
+ routing time + forwarding recovery time. A smaller value of each item means a smaller MTTR and a
higher availability.

2
High availability technologies
Increasing MTBF or decreasing MTTR can enhance the availability of a network. The high availability
technologies described in this section meet the level 2 and level 3 high availability requirements by
decreasing MTTR.
High availability technologies can be classified as fault detection technologies or protection switchover
technologies.
Fault detection technologies
Fault detection technologies enable detection and diagnosis of network faults. CFD, DLDP, and Ethernet
OAM are data link layer fault detection technologies. BFD is a generic fault detection technology that
can be used at any layer. NQA is used for diagnosis and evaluation of network quality. Monitor Link and
Track work along with other high availability technologies to detect faults through a collaboration
mechanism.
Table 2 Fault detection technologies
Technolo
gy
Introduction Reference
CFD
Connectivity Fault Detection (CFD), which conforms to IEEE
802.1ag Connectivity Fault Management (CFM), is an end-to-end
per-VLAN link layer Operations, Administration and Maintenance
(OAM) mechanism used for link connectivity detection, fault
verification, and fault location.
"Configuring CFD" in
High Availability
Configuration Guide
DLDP
The Device link detection protocol (DLDP) deals with unidirectional
links that may occur in a network. Upon detecting a unidirectional
link, DLDP, as configured, can shut down the related port
automatically or prompt users to take actions to avoid network
problems.
"Configuring DLDP" in
High Availability
Configuration Guide
Ethernet OAM
As a tool monitoring Layer 2 link status, Ethernet OAM is mainly
used to address common link-related issues on the "last mile". You
can monitor the status of the point-to-point link between two directly
connected devices by enabling Ethernet OAM on them.
"Configuring Ethernet
OAM" in High
Availability
Configuration Guide
BFD
Bidirectional forwarding detection (BFD) provides a single
mechanism to quickly detect and monitor the connectivity of links
or IP forwarding in networks. To improve network performance,
devices must quickly detect communication failures to restore
communication through backup paths as soon as possible.
"Configuring BFD" in
High Availability
Configuration Guide
NQA
Network Quality Analyzer (NQA) analyzes network performance,
services and service quality through sending test packets, and
provides you with network performance and service quality
parameters such as jitter, TCP connection delay, FTP connection
delay and file transfer rate.
"Configuring NQA"
in Network
Management and
Monitoring
Configuration Guide
Monitor Link
Monitor Link works together with Layer 2 topology protocols to
adapt the up/down state of a downlink port to the state of an uplink
port. This feature enables fast link switchover on a downstream
device in response to the uplink state change on its upstream
device.
"Configuring Monitor
Link" in High
Availability
Configuration Guide

3
Technolo
gy
Introduction Reference
Track
The track module is used to implement collaboration between
different modules. The collaboration here involves three parts: the
application modules, the track module, and the detection modules.
These modules collaborate with one another through collaboration
entries. That is, the detection modules trigger the application
modules to perform certain operations through the track module.
More specifically, the detection modules probe the link status,
network performance and so on, and inform the application
modules of the detection result through the track module. Once
notified of network status changes, the application modules deal
with the changes to avoid communication interruption and network
performance degradation.
"Configuring track" in
High Availability
Configuration Guide
Protection switchover technologies
Protection switchover technologies aim at recovering network faults. They back up hardware, link, routing,
and service information for switchover in case of network faults, to ensure continuity of network services.
Table 3 Protection switchover technologies
Technolo
gy
Introduction Reference
Ethernet Link
Aggregation
Ethernet link aggregation, most often simply called link
aggregation, aggregates multiple physical Ethernet links into one
logical link to increase link bandwidth beyond the limits of any one
single link. This logical link is an aggregate link. It allows for link
redundancy because the member physical links can dynamically
back up one another.
"Configuring Ethernet
ink aggregation" in
Layer 2
—
LAN
Switching
Configuration Guide
Smart Link
Smart Link is a feature developed to address the slow convergence
issue with STP. It provides link redundancy as well as fast
convergence in a dual uplink network, allowing the backup link to
take over quickly when the primary link fails.
"Configuring Smart
Link" in High
Availability
Configuration Guide
MSTP
As a Layer 2 management protocol, the Multiple Spanning Tree
Protocol (MSTP) eliminates Layer 2 loops by selectively blocking
redundant links in a network, and in the mean time, allows for link
redundancy.
"Configuring
spanning tree" in
Layer 2—LAN
Switching
Configuration Guide
RRPP
The Rapid Ring Protection Protocol (RRPP) is a link layer protocol
designed for Ethernet rings. RRPP can prevent broadcast storms
caused by data loops when an Ethernet ring is healthy, and rapidly
restore the communication paths between the nodes in the event
that a link is disconnected on the ring.
"Configuring RRPP" in
High Availability
Configuration Guide
GR
Graceful Restart (GR) ensures the continuity of packet forwarding
when a protocol, such as BGP, OSPF, IPv6 BGP, or OSPFv3,
restarts or during an active/standby switchover process. It needs
other devices to implement routing information backup and
recovery.
Layer 3—IP Routing
Configuration
Guide/Configuration
Guide of the
corresponding
protocols

4
Technolo
gy
Introduction Reference
VRRP
Virtual Router Redundancy Protocol (VRRP) is an error-tolerant
protocol that provides highly reliable default links on multicast and
broadcast LANs such as Ethernet, avoiding network interruption
due to failure of a single link.
"Configuring VRRP"
in High Availability
Configuration Guide
A single availability technology cannot solve all problems. Therefore, a combination of availability
technologies, chosen on the basis of detailed analysis of network environments and user requirements,
should be used to enhance network availability. For example, access-layer devices should be connected
to distribution-layer devices over redundant links, and core-layer devices should be fully meshed. Also,
network availability should be considered during planning prior to building a network.

5
Configuring Ethernet OAM
Ethernet OAM overview
Ethernet Operation, Administration and Maintenance (OAM) is a tool that monitors Layer 2 link status
and addresses common link-related issues on the "last mile." You can use it to monitor the status of the
point-to-point link between two directly connected devices.
Major functions of Ethernet OAM
Ethernet OAM provides the following functions:
•Link performance monitoring—Monitors the performance indices of a link, including packet loss,
delay, and jitter, and collects traffic statistics of various types
•Fault detection and alarm—Checks the connectivity of a link by sending OAM protocol data units
(OAMPDUs) and reports to the network administrators when a link error occurs
•Remote loopback—Checks link quality and locates link errors by looping back OAMPDUs
Ethernet OAMPDUs
Ethernet OAM works on the data link layer. Ethernet OAM reports the link status by periodically
exchanging OAMPDUs between devices so that the administrator can effectively manage the network.
Ethernet OAMPDUs fall into the following types: Information, Event Notification, and Loopback Control.
Figure 1 Formats of different types of Ethernet OAMPDUs
Table 4 Fields in an OAMPDU
Field Descri
p
tion
Dest addr
Destination MAC address of the Ethernet OAMPDU
It is a slow protocol multicast address, 0180c2000002. Bridges cannot forward
slow protocol packets, so Ethernet OAMPDUs cannot be forwarded.
Source addr Source MAC address of the Ethernet OAMPDU
It is the bridge MAC address of the sending side and is a unicast MAC address.
Type Type of the encapsulated protocol in the Ethernet OAMPDU
The value is 0x8809.

6
Field Descri
p
tion
Subtype The specific protocol being encapsulated in the Ethernet OAMPDU
The value is 0x03.
Flags Status information of an Ethernet OAM entity
Code Type of the Ethernet OAMPDU
NOTE:
Throughout this document, a port with Ethernet OAM enabled is an Ethernet OAM entity or an OAM
entity.
Table 5 Functions of different types of OAMPDUs
OAMPDU t
yp
e Function
Information OAMPDU
Used for transmitting state information of an Ethernet OAM entity—including the
information about the local device and remote devices and customized
information—to the remote Ethernet OAM entity and maintaining OAM connections.
Event Notification
OAMPDU
Used by link monitoring to notify the remote OAM entity when it detects problems on
the link in between.
Loopback Control
OAMPDU
Used for remote loopback control. By inserting the information used to
enable/disable loopback to a loopback control OAMPDU, you can enable/disable
loopback on a remote OAM entity.
How Ethernet OAM works
This section describes the working procedures of Ethernet OAM.
Ethernet OAM connection establishment
Ethernet OAM connection is the basis of all the other Ethernet OAM functions. OAM connection
establishment is also known as the "Discovery phase", where an Ethernet OAM entity discovers remote
OAM entities and establishes sessions with them.
In this phase, interconnected OAM entities determine whether Ethernet OAM connections can be
established, by exchanging Information OAMPDUs to notify the peer of their OAM configuration
information and the OAM capabilities of the local nodes. An Ethernet OAM connection can be
established between entities that have matching Loopback, link detecting, and link event settings. After
an Ethernet OAM connection is established, Ethernet OAM takes effect on both sides.
For Ethernet OAM connection establishment, a device can operate in active Ethernet OAM mode or
passive Ethernet OAM mode, but a switch role will be somewhat different depending on the mode.
Table 6 Active Ethernet OAM mode and passive Ethernet OAM mode
Item Active Ethernet OAM mode
Passive Ethernet OAM mode
Initiating OAM Discovery Available Unavailable
Responding to OAM Discovery Available Available
Transmitting Information
OAMPDUs Available Available

7
Item Active Ethernet OAM mode
Passive Ethernet OAM mode
Transmitting Event Notification
OAMPDUs Available Available
Transmitting Information
OAMPDUs without any TLV Available Available
Transmitting Loopback Control
OAMPDUs Available Unavailable
Responding to Loopback Control
OAMPDUs
Available—if both sides operate in
active OAM mode Available
NOTE:
•Only OAM entities operating in active OAM mode can initiate OAM connections. OAM entities
operating in passive mode wait and respond to the connection requests sent by their peers.
•No OAM connection can be established between OAM entities operating in passive OAM mode.
After an Ethernet OAM connection is established, the Ethernet OAM entities on both sides exchange
Information OAMPDUs at the handshake packet transmission interval to check whether the Ethernet
OAM connection is normal. If an Ethernet OAM entity receives no Information OAMPDU within the
Ethernet OAM connection timeout time, the Ethernet OAM connection is considered disconnected.
Link monitoring
Error detection in an Ethernet is difficult, especially when the physical connection in the network is not
disconnected but network performance is degrading gradually. Link monitoring is used to detect and
indicate link faults in various environments. Ethernet OAM implements link monitoring through the
exchange of Event Notification OAMPDUs. When detecting one of the link error events listed in Table 7,
the local OAM entity sends an Event Notification OAMPDU to notify the remote OAM entity. With the
log information, network administrators can keep track of network status promptly.
Table 7 Ethernet OAM link error events
Ethernet OAM link events Descri
p
tion
Errored symbol event
An errored symbol event occurs when the number of detected symbol
errors during a specified detection interval exceeds the predefined
threshold.
Errored frame event An errored frame event occurs when the number of detected error
frames during a specified interval exceeds the predefined threshold.
Errored frame period event
An errored frame period event occurs if the number of frame errors in
a specific number of received frames exceeds the predefined
threshold.
Errored frame seconds event
An errored frame seconds event occurs when the number of error
frame seconds detected on a port during a specified detection
interval reaches the error threshold.
The system transforms the period of detecting errored frame period events into the maximum number of
64-byte frames (excluding the interframe spacing and preamble) that a port can send in the specified
period. The system takes the maximum number of frames sent as the period. The maximum number of
frames sent is calculated using this formula: the maximum number of frames = interface bandwidth (bps)
× errored frame period event detection period (in ms)/(64 × 8 × 1000).

8
A second in which errored frames appear is called an "errored frame second."
Remote fault detection
Information OAMPDUs are exchanged periodically among Ethernet OAM entities across established
OAM connections. In a network where traffic is interrupted due to device failures or unavailability, the
flag field defined in information OAMPDUs allows an Ethernet OAM entity to send error
information—the critical link event type—to its peer. You can use the log information to track ongoing link
status and troubleshoot problems promptly.
Table 8 Critical link events
T
yp
e Descri
p
tion OAMPDU transmission fre
q
uencies
Link Fault Peer link signal is lost. Once per second
Dying Gasp A power failure or other unexpected error
occurred. Non-stop
Critical Event An undetermined critical event occurred. Non-stop
This Switch Series is able to receive information OAMPDUs carrying the critical link events listed in Table
8.
Only the Gigabit fiber ports are able to send information OAMPDUs carrying Link Fault events.
This Switch Series is able to send information OAMPDUs carrying Dying Gasp events when the device is
rebooted or relevant ports are manually shut down. Physical IRF ports, however, are unable to send this
type of OAMPDU. For more information about physical IRF ports, see IRF Configuration Guide.
This Switch Series is unable to send information OAMPDUs carrying Critical Events.
Remote loopback
Remote loopback is available only after the Ethernet OAM connection is established. With remote
loopback enabled, the Ethernet OAM entity operating in active Ethernet OAM mode sends
non-OAMPDUs to its peer. After receiving these frames, the peer does not forward them according to
their destination addresses. Instead, it returns them to the sender along the original path.
Remote loopback enables you to check the link status and locate link failures. Performing remote
loopback periodically helps to detect network faults promptly. Furthermore, performing remote loopback
by network segments helps to locate network faults.
Standards and protocols
Ethernet OAM is defined in IEEE 802.3ah (Carrier Sense Multiple Access with Collision Detection
(CSMA/CD) Access Method and Physical Layer Specifications.
Ethernet OAM configuration task list
Task Remarks
Configuring basic Ethernet OAM functions Required
Configuring link
monitoring
Configuring errored symbol event detection Optional
Configuring errored frame event detection Optional
Configuring errored frame period event detection Optional

9
Task Remarks
Configuring errored frame seconds event detection
Optional
Configuring Ethernet
OAM remote
loopback
Enabling Ethernet OAM remote loopback Optional
Rejecting the Ethernet OAM remote loopback
request from a remote port Optional
Configuring basic Ethernet OAM functions
For Ethernet OAM connection establishment, an Ethernet OAM entity operates in active mode or passive
mode. Only an Ethernet OAM entity in active mode can initiate connection establishment. After Ethernet
OAM is enabled on an Ethernet port, according to its Ethernet OAM mode, the Ethernet port establishes
an Ethernet OAM connection with its peer port.
To change the Ethernet OAM mode on an Ethernet OAM-enabled port, you must first disable Ethernet
OAM on the port.
To configure basic Ethernet OAM functions:
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Enter Layer 2 Ethernet
interface view.
interface interface-type
interface-number N/A
3. Set the Ethernet OAM mode. oam mode { active | passive }
Optional.
The default is active Ethernet OAM
mode.
4. Enable Ethernet OAM on the
current port. oam enable Ethernet OAM is disabled by
default.
Configuring link monitoring
After Ethernet OAM connections are established, the link monitoring periods and thresholds configured
in this section take effect on all Ethernet ports automatically.
Configuring errored symbol event detection
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Configure the errored
symbol event detection
interval. oam errored-symbol period period-value Optional.
1 second by default.
3. Configure the errored
symbol event triggering
threshold.
oam errored-symbol threshold
threshold-value
Optional.
1 by default.

10
Configuring errored frame event detection
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Configure the errored frame
event detection interval. oam errored-frame period
period-value
Optional.
1 second by default.
3. Configure the errored frame
event triggering threshold. oam errored-frame threshold
threshold-value
Optional.
1 by default.
Configuring errored frame period event detection
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Configure the errored
frame period event
detection period.
oam errored-frame-period period
period-value
Optional.
1000 milliseconds by default.
3. Configure the errored
frame period event
triggering threshold.
oam errored-frame-period threshold
threshold-value
Optional.
1 by default.
Configuring errored frame seconds event detection
IMPORTANT:
Make sure the errored frame seconds tri
gg
erin
g
threshold is less than the errored frame seconds detection
interval. Otherwise, no errored frame seconds event can be generated.
To configure errored frame seconds event detection:
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Configure the errored frame
seconds event detection
interval.
oam errored-frame-seconds
period period-value
Optional.
60 second by default.
3. Configure the errored frame
seconds event triggering
threshold.
oam errored-frame-seconds
threshold threshold-value
Optional.
1 by default.
Configuring Ethernet OAM remote loopback
Enabling Ethernet OAM remote loopback

11
CAUTION:
Use this function with caution, because enabling Ethernet OAM remote loopback impacts other services.
When you enable Ethernet OAM remote loopback on a port, the port sends Loopback Control
OAMPDUs to a remote port, and the remote port enters the loopback state. The port then sends test
frames to the remote port. By observing how many of these test frames return, you can calculate the
packet loss ratio on the link to evaluate the link performance.
You can enable Ethernet OAM remote loopback on a specific port in user view, system view, or Layer 2
Ethernet interface view. The configuration effects are the same.
Configuration guidelines
•Ethernet OAM remote loopback is available only after the Ethernet OAM connection is established
and can be performed only by Ethernet OAM entities operating in active Ethernet OAM mode.
•Remote loopback is available only on full-duplex links that support remote loopback at both ends.
•Ethernet OAM remote loopback must be supported by both the remote port and the sending port.
•Enabling Ethernet OAM remote loopback interrupts data communications. After Ethernet OAM
remote loopback is disabled, all the ports involved will shut down and then come up. Ethernet OAM
remote loopback can be disabled by any of the following actions: executing the undo oam enable
command to disable Ethernet OAM; executing the undo oam loopback interface or undo oam
loopback command to disable Ethernet OAM remote loopback; and Ethernet OAM connection
timing out.
•Ethernet OAM remote loopback is only applicable to individual links. It is not applicable to link
aggregation member ports or service loopback group member ports. In addition, do not assign
ports where Ethernet OAM remote loopback is being performed to link aggregation groups or
service loopback groups. For more information about link aggregation groups and service
loopback groups, see Layer 2—LAN Switching Configuration Guide.
•Enabling internal loopback test on a port in remote loopback test can terminate the remote
loopback test. For more information about loopback test, see Layer 2—LAN Switching
Configuration Guide.
Configuration procedure
To enable Ethernet OAM remote loopback in user view:
Task Command
Remarks
Enable Ethernet OAM remote
loopback on a specific port.
oam loopback interface
interface-type interface-number Disabled by default.
To enable Ethernet OAM remote loopback in system view:
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Enable Ethernet OAM remote
loopback on a specific port.
oam loopback interface
interface-type interface-number Disabled by default.
To enable Ethernet OAM remote loopback in Layer 2 Ethernet interface view:

12
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Enter Layer 2 Ethernet
interface view.
interface interface-type
interface-number N/A
3. Enable Ethernet OAM remote
loopback on the port. oam loopback Disabled by default.
Rejecting the Ethernet OAM remote loopback request from a
remote port
The Ethernet OAM remote loopback function impacts other services. To solve this problem, you can
disable a port from being controlled by the Loopback Control OAMPDUs sent by a remote port. The local
port then rejects the Ethernet OAM remote loopback request from the remote port.
To reject the Ethernet OAM remote loopback request from a remote port:
Ste
p
Command
Remarks
1. Enter system view. system-view N/A
2. Enter Layer 2 Ethernet
interface view.
interface interface-type
interface-number N/A
3. Reject the Ethernet OAM
remote loopback request from
a remote port.
oam loopback reject-request
By default, a port does not reject
the Ethernet OAM remote
loopback request from a remote
port.
Displaying and maintaining Ethernet OAM
configuration
Task Command
Remarks
Display global Ethernet OAM
configuration.
display oam configuration [ |{ begin
| exclude | include }
regular-expression ]
Available in any view
Display the statistics on critical
events after an Ethernet OAM
connection is established.
display oam critical-event [interface
interface-type interface-number ] [ |
{ begin | exclude | include }
regular-expression ]
Available in any view
Display the statistics on Ethernet
OAM link error events after an
Ethernet OAM connection is
established.
display oam link-event {local |
remote } [ interface interface-type
interface-number ] [ |{ begin |
exclude | include }
regular-expression ]
Available in any view

13
Task Command
Remarks
Display the information about an
Ethernet OAM connection.
display oam {local | remote }
[interface interface-type
interface-number ] [ |{ begin |
exclude | include }
regular-expression ]
Available in any view
Clear statistics on Ethernet OAM
packets and Ethernet OAM link
error events.
reset oam [interface interface-type
interface-number ]Available in user view
Ethernet OAM configuration example
Network requirements
On the network shown in Figure 2, perform the following operations:
•Enable Ethernet OAM on Device A and Device B to auto-detect link errors between the two devices
•Monitor the performance of the link between Device A and Device B by collecting statistics about
the error frames received by Device A
Figure 2 Network diagram
Configuration procedure
1. Configure Device A:
# Configure GigabitEthernet 1/0/1 to operate in passive Ethernet OAM mode and enable
Ethernet OAM for it.
<DeviceA> system-view
[DeviceA] interface gigabitethernet 1/0/1
[DeviceA-GigabitEthernet1/0/1] oam mode passive
[DeviceA-GigabitEthernet1/0/1] oam enable
[DeviceA-GigabitEthernet1/0/1] quit
# Set the errored frame detection interval to 20 seconds and set the errored frame event triggering
threshold to 10.
[DeviceA] oam errored-frame period 20
[DeviceA] oam errored-frame threshold 10
2. Configure Device B:
# Configure GigabitEthernet 1/0/1 to operate in active Ethernet OAM mode (the default) and
enable Ethernet OAM for it.
<DeviceB> system-view
[DeviceB] interface gigabitethernet 1/0/1
[DeviceA-GigabitEthernet1/0/1] oam mode active
[DeviceB-GigabitEthernet1/0/1] oam enable
[DeviceB-GigabitEthernet1/0/1] quit
3. Verify the configuration: