H3C S9500E Series Configuration Manual page 23

The interval to send Information OAMPDUs is determined by a timer. Up to ten Information OAMPDUs can
be sent in a second.
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. Upon 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
Errored symbol event
Errored frame event
Errored frame period event
Errored frame seconds event
The system transforms the period of detecting errored frame period events into the maximum number of
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64-byte frames that a port can send in the specified period, that is, 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).
A second in which errored frames appear is called an errored frame second.
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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 switch failures or
unavailability, the flag field defined in information OAMPDUs allows an Ethernet OAM entity to
send error information to its peer. You can use the log information to track ongoing link status
and troubleshoot problems promptly.
frequencies of the corresponding OAMPDUs.
Description
An errored symbol event occurs when the number of detected symbol
errors over a specified detection interval exceeds the predefined
threshold.
An errored frame event occurs when the number of detected error frames
over a specified interval exceeds the predefined threshold.
An errored frame period event occurs if the number of frame errors in
specified number of received frames exceeds the predefined threshold.
When the number of error frame seconds detected on a port over a
detection interval reaches the error threshold, an errored frame seconds
event occurs.
Table 8 lists critical link events and the transmission
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