Technical Documentation

Example: Configuring Ethernet OAM Link Fault Management on EX Series Switches

JUNOS Software for EX Series switches allows the Ethernet interfaces on these switches to support the IEEE 802.3ah standard for the Operation, Administration, and Maintenance (OAM) of Ethernet in access networks. The standard defines OAM link fault management (LFM). You can configure IEEE 802.3ah OAM LFM on point-to-point Ethernet links that are connected either directly or through Ethernet repeaters.

This example describes how to enable and configure OAM LFM on a Gigabit Ethernet interface:

Requirements

This example uses the following hardware and software components:

  • JUNOS Release 9.4 or later for EX Series switches
  • Two EX3200 or EX4200 switches connected directly

Overview and Topology

JUNOS Software for EX Series switches allows the Ethernet interfaces on these switches to support the IEEE 802.3ah standard for the Operation, Administration, and Maintenance (OAM) of Ethernet in access networks. The standard defines OAM link fault management (LFM). You can configure IEEE 802.3ah OAM LFM on point-to-point Ethernet links that are connected either directly or through Ethernet repeaters.

This example uses two EX4200 switches connected directly. Before you begin configuring Ethernet OAM LFM on two switches, connect the two switches directly through a trunk interface.

Configuring Ethernet OAM Link Fault Management on Switch 1

CLI Quick Configuration

To quickly configure Ethernet OAM LFM, copy the following commands and paste them into the switch terminal window:


[edit protocols oam ethernet link-fault-management]
set interface ge-0/0/0
set interface ge-0/0/0 link-discovery active
set interface ge-0/0/0 pdu-interval 800
set interface ge-0/0/0 remote-loopback

Step-by-Step Procedure

To configure Ethernet OAM LFM on switch 1:

  1. Enable IEEE 802.3ah OAM support on an interface:

    [edit protocols oam ethernet link-fault-management]
    user@switch1# set interface ge-0/0/0

  2. Specify that the interface initiates the discovery process by configuring the link discovery mode to active:

    [edit protocols oam ethernet link-fault-management]
    user@switch1# set interface ge-0/0/0 link-discovery active

  3. Set the periodic OAM PDU-sending interval (in milliseconds) to 800 on switch 1:

    [edit protocols oam ethernet link-fault-management]
    user@switch1# set interface pdu-interval 800

  4. Set a remote interface into loopback mode so that all frames except OAM PDUs are looped back without any changes made to the frames. Ensure that the remote DTE supports remote loopback mode. To set the remote DTE in loopback mode

    [edit protocols oam ethernet link-fault-management]
    user@switch1# set interface ge-0/0/0.0 remote-loopback

Results

Check the results of the configuration:


[edit]


user@switch1# show
protocols {
oam {
ethernet {
link-fault-management {
interface ge-0/0/0 {
pdu-interval 800;
link-discovery active;
remote-loopback;
}
}
}
}

Configuring Ethernet OAM Link Fault Management on Switch 2

CLI Quick Configuration

To quickly configure Ethernet OAM LFM on switch 2, copy the following commands and paste them into the switch terminal window:


[edit protocols oam ethernet link-fault-management ]
set interface ge-0/0/1
set interface ge-0/0/1 negotiation-options allow-remote-loopback

Step-by-Step Procedure

To configure Ethernet OAM LFM on switch 2:

  1. Enable OAM on the peer interface on switch 2:

    [edit protocols oam ethernet link-fault-management]
    user@switch2# set interface ge-0/0/1

  2. Enable remote loopback support for the local interface:

    [edit protocols oam ethernet link-fault-management]
    user@switch2# set interface ge-0/0/1 negotiation-options allow-remote-loopback

Results

Check the results of the configuration:

[edit]
user@switch2# show
protocols {
oam {
ethernet {
link-fault-management {
interface ge-0/0/1 {
negotiation-options {
allow-remote-loopback;
}
}
}
}
}

Verification

Verifying That OAM LFM Has Been Configured Properly

Purpose

Verify that OAM LFM has been configured properly.

Action

Use the show oam ethernet link-fault-management command:

Sample Output

Interface: ge-0/0/0.0
Status: Running, Discovery state: Send Any
Peer address: 00:19:e2:50:3b:e1
Flags:Remote-Stable Remote-State-Valid Local-Stable 0x50
Remote entity information:
Remote MUX action: forwarding, Remote parser action: forwarding
Discovery mode: active, Unidirectional mode: unsupported
Remote loopback mode: supported, Link events: supported
Variable requests: unsupported

Meaning

When the output displays the MAC address and the discover state is Send Any, it means that OAM LFM has been configured properly.


Published: 2009-07-27