H3C Technologies H3C S3100 Series Switches - Manual (Page 1030)

1-5
z The system transforms the period of detecting errored frame period events into the maximum
number of 64-byte frames that a port can send in the specific 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)
z If errored frames appear in a certain second, this second is called an errored frame second.
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 device failures or unavailability, the
flag field defined in information OAMPDUs allows an Ethernet OAM entity to send error information to
its peer. In this way, you can keep track of link status in time through the log information and
troubleshoot in time. Table 1-5 lists the critical link events and the transmission frequencies of the
corresponding OAMPDUs.
Table 1-5 Critical link error events
Ethernet OAM link events Description
Link Fault Peer link signal is lost.
Dying Gasp An unexpected fault, such as power failure, occurred.
Critical event An undetermined critical event happened.
Remote loopback
Remote loopback is available only after the Ethernet OAM connection is established. With remote
loopback enabled, the Ethernet OAM entity operating in active Ethernet OAM mode sends
non-OAMPDUs to its peer. After receiving these PDUs, the peer does not forward them according to
their destination addresses. Instead, it returns them to the sender along the original path.
Remote loopback enables you to check the link status and locate link failures. Performing remote
loopback periodically helps to detect network faults in time. Furthermore, performing remote loopback
by network segments helps to locate network faults.
Standards and Protocols
Ethernet OAM is defined in IEEE 802.3h (Carrier Sense Multiple Access with Collision Detection
(CSMA/CD) Access Method and Physical Layer Specifications).
Ethernet OAM Configuration Task List
Complete the following tasks to configure Ethernet OAM:
Task Remarks
Configuring Basic Ethernet OAM Functions Required
Configuring the Ethernet OAM Connection Detection Timers Required