Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010 Configuration Manual page 275

messages or OAM PDUs are of standard length, untagged Ethernet frames within
the normal frame length limits in the range 64–1518 bytes.
To configure OAM link-fault management on an Ethernet interface:
Specify a Fast Ethernet, Gigabit Ethernet, or 10-Gigabit Ethernet interface, and
1.
enable IEEE 802.3ah OAM support on the interface. When the IEEE 802.3ah
OAM protocol is enabled on a physical interface, the discovery process is
automatically triggered. The default discovery mode of a local interface is active.
host1(config)#interface GigabitEthernet 6/0
host1(config-if)#ethernet oam lfm
NOTE: You must enable the OAM link-fault management feature to be able to
configure parameters that govern the link monitoring and management process.
All of the following steps are optional. You can choose which of the OAM
configurations you want to set up on the interface to enable link-fault administration.
If you enable OAM support on the interface without specifying any of the other
parameters, such as discovery mode and threshold settings, default values are
assumed for those attributes.
Specify whether the interface or the peer initiates the discovery process by
2.
configuring the link discovery mode to active or passive.
host1(config-if)#ethernet oam lfm mode active
In this case, the discovery mode of the interface is set as active. In active mode,
the interface discovers and monitors the peer on the link if the peer also supports
IEEE 802.3ah OAM functionality. An OAM entity in active mode initiates the
discovery process by sending an Information OAM PDU to the multicast address
of the slow protocol (0180.c200.0002) at a configured rate. In a carrier
environment, the customer edge (CE) devices are normally configured for passive
mode operation, whereas the provider edge (PE) equipment is configured for
active mode operation.
Specify the frequency, in milliseconds, at which OAM PDUs are sent to the peer
3.
to keep the OAM association alive.
host1(config-if)#ethernet oam lfm pdu-transmit-interval 200
In this example, the local interface is configured to send Information OAM PDUs
every 200 milliseconds to the remote peer. This OAM PDU includes local, remote,
and organization-specific information, and contains a local-information TLV.
The rate of transmission of OAM PDUs can be a number in the range 100–1000
milliseconds; the default value is 1000 milliseconds.
Specify the number of OAM PDUs that a local OAM client can fail to receive from
4.
a remote peer before a link-fault event is triggered. The product of the PDU timer
and the PDU loss threshold equals the lost-link timer value, which is used to reset
the Discovery state diagram that maintains the states of the OAM entities and
determines the condition of the link based on various stored values.
Chapter 7: Configuring IEEE 802.3ah OAM Link-Fault Management
Configuring 802.3ah OAM Link-Fault Management
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