H3C S3610-28F, Operation Manual

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Operation Manual – OAM
H3C S3610&S5510 Series Ethernet Switches
Chapter 1 OAM Configuration
1-3
As for OAM connection establishment, a device can operate in two modes: active OAM
mode and passive OAM mode. Only devices operating in active OAM mode can initiate
OAM connection establishment processes. Those operating in passive OAM mode,
however, wait and respond to OAM connection establishment requests and take
corresponding operations. Table 1-1 compares active OAM mode with passive OAM
mode.
Table 1-1 Active OAM mode and passive OAM mode
Item Active OAM mode Passive OAM mode
Initiating OAM Discovery Available Unavailable
Responding to OAM Discovery Available Available
Transmitting Information OAMPDUs Available Available
Transmitting Event Notification
OAMPDUs
Available Available
Transmitting Information OAMPDUs
with the Data/Pad field being empty
Available Available
Transmitting Loopback Control
OAMPDUs
Available Unavailable
Responding to Loopback Control
OAMPDUs
Available (if both
sides operate in
active OAM mode)
Available
Transmitting organization-specific
OAMPDUs
Available Available
After an OAM connection is established, the OAM entities on both sides exchange
Information OAMPDUs periodically to keep the OAM connection valid. If an OAM entity
receives no Information OAMPDU for five seconds, the OAM connection is considered
invalid. In this case, to enable the OAM entities to communicate with each other again,
a new OAM connection is required.
The interval to send Information OAMPDUs is determined by a timer. Up to ten
Information OAMPDUs can be sent in a second.
II. Link Monitoring
Link monitoring is used to detect and locate link faults in various environments. In OAM,
link faults are categorized into link events.
OAM implements link monitoring through the exchange of Event Notification
OAMPDUs. Upon detecting a link fault, the local device sends an Event Notification
OAMPDU to the remote OAM entity to report the fault event. Link monitoring enables
network administrators to be informed of network status in time. Table 1-2 describes the
link events.