Juniper JUNOSE 11.1.X - LINK LAYER CONFIGURATION 4-7-2010, Руководство по настройке

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You can configure the OAM discovery function in JUNOSe Software per Ethernet
major interface as either active or passive mode. The OAM state machine labels a
port to be in the operational down state until the discovery process is completed
successfully. You can configure the PDU timer, which is the rate at which Information
OAM PDUs are sent to the remote peer to keep the OAM association active, in the
range of milliseconds with a maximum value of 1000 (the default value) and a
minimum value of 100. Also, you can configure the local OAM function with a packet
loss threshold, which specifies the number of Information OAM PDUs that an interface
can miss before the link between peers is considered down. When the PDU loss
threshold is exceeded, 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.
When the PDU loss threshold is exceeded, the OAM function signals a problem with
the link and the link is immediately transitioned to the down state. When the OAM
association with the peer is rediscovered after a successful discovery operation, the
link transitions to the up state.
NOTE: The operational status displayed in the output of the show commands related
to interface settings will be down if the OAM session is down owing to loss of
association.
Related Topics
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OAM Feature Overview on page 234
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OAM Messages on page 230
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Configuring 802.3ah OAM Link-Fault Management on page 242
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Monitoring OAM Link-Fault Management Discovery Settings for an Interface on
page 250
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ethernet oam lfm
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ethernet oam lfm mode
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ethernet oam lfm pdu-lost-threshold
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ethernet oam lfm pdu-transmit-interval
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show ethernet oam lfm discovery
OAM Link Monitoring Feature
The router performs link monitoring by sending periodic Information OAM PDUs to
advertise OAM mode, configuration, and capabilities. Link monitoring uses the Event
Notification OAM PDU and sends events to the remote OAM entity when problems
are observed on the link. You can configure the OAM application to track frame and
symbol errors on the link to analyze the overall health and quality of the link. Frame
errors include frameTooLong, lengthError (runts), alignmentError, and
frameCheckSequence errors.
236 ■
OAM Link Monitoring Feature
JUNOSe 11.1.x Link Layer Configuration Guide