Huawei Quidway S3700 Series Configuration Manual page 165

Quidway S3700 Series Ethernet Switches
Configuration Guide - Reliability
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Issue 01 (2011-10-26)
– MD
A maintenance domain (MD) is a network or a part of the network where CFM is
performed. Devices in an MD are managed by a single ISP.
– Default MD
According to IEEE Standard 802.1ag-2007, each device can be configured with one
default MD. The default MD must be of a higher level than all MDs to which MEPs
configured on the local device belong. In addition, the default MD must be of the same
level as the high-level MD. The default MD transmits high-level CCMs and creates
MIPs to reply LTR packets.
– MA
A maintenance association (MA) is a part of an MD. An MD can be divided into one
or multiple MAs. On the S3700, an MA is associated with a VLAN. Ethernet CFM
checks connectivity in each MA.
– MEP
A maintenance association end point (MEP) is an edge node of an MA.
For a network device running Ethernet CFM, its MEP is called the local MEP. For the
other devices in the same MA, their MEPs are called the remote maintenance association
end points (RMEPs).
CAUTION
One Trunk interface can be configured with only one MEP.
– MIP
A maintenance association intermediate point (MIP) is an internal node of an MA.
MIPs reside on the interfaces on the S3700 and are automatically created by the
S3700.
Connectivity check
Ethernet CFM divides a network into one MD or multiple MDs. Each MD is divided into
one MA or multiple MAs. The MEPs in an MA exchange Continuity Check messages
(CCMs) periodically to detect the connectivity between them.
Fault acknowledgement
– 802.1ag MAC ping
Similar to ping, 802.1ag MAC ping sends test packets and waits for a reply to test
whether the destination device is reachable. 802.1ag MAC ping is initiated by a MEP
and destined for an RMEP or MIP in the same MA.
– Gmac ping
Gmac ping works similarly to 802.1ag MAC ping. A MEP, however, is not required to
initiate Gmac ping. The destination node may not be an RMEP or a MIP. Gmac ping
can be implemented without configuring the MD, MA, or MEP on the source device,
the intermediate device, and the destination device.
Fault location
– 802.1ag MAC trace
Similar to traceroute (or tracert for short), 802.1ag MAC trace sends test packets and
waits for a reply to test the path between the local device and the destination device and
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4 Ethernet OAM Configuration
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