SNR S2940-8G-v2, Руководство по настройке

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SNR S2940-8G-v2 Switch Configuration Guide
CFM-OAM Configuration
• MEP received the failure MEPID or MAID, represent there is exist of internal configuration
failure in MA or cross connection failure;
• MEP receive the lower level of the CCM messages, represent there is exist of internal con-
figuration failure in MA or cross connection failure;
• MEP receive the CCM message which carries MAC status information, can investigate the
outside failure of MA;
C
CM
MEP3
CCM
MEP2
MEP1
CCM
MIP
MIP
MEP
MA
Figure 15.3: Connectedness inspection sketch map
15.3.2 Path Discovery
MEP and MIP will through the Linktrace to complete. The function of 802.1ag Linktrace is more
or less the same with IP Traceroute. Through send the testing messages and receive replay
messages to check the path of destination facilities or orientate the failure point. The processes
as follow: MEP send LTM to the target MP (MEP or MIP), each of the MIP after receiving the LTM
will also send a LTR to source MEP. And then, transmit the LTM messages, until the LTM arrive to
destination MP or cannot transmit at all. Source MEP according to feedback LTR to confirm the
status of the linkage, and obtains the paths to target MAC. It shows in the Figure 15.4.
LTM destination MAC address is the group broadcast address. The last 3 bit in the group
broadcast address represents the level of different maintenance domain. LTR is the one way
messages, the destination address as the LTM source MAC address.
15.3.3 Confirmation and Orientation of Failure
It can be actualizing by the 802.1ag Linktrace function that mention above. Also it can be actu-
alizing by 802.1ag Loopback function as well. The circulation function is more or less the same
with IP Ping, through out the sending of testing messages and receiving the replay messages to
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