HP 5500 Ei 5500 Si Switch Series Configuration Guide

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By cooperating with MEPs, a MIP can perform a function similar to ping and traceroute. Like a MEP, 
a MIP forwards packets of a diffe rent level without any processing and only processes packets of 
its level.  
Figure 6  dem
 onstrates a grading example of the CF D module. Six devices, labeled A through F 
respectively, exist. Suppose each device has tw o ports, and MEPs and MIPs are configured on 
some of these ports. Four levels of MDs are desi gned in this example, the bigger the number, the...

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Continuity check 
Connectivity faults are usually caused by device faults or configuration errors. Continuity check checks 
the connectivity between MEPs. This function is implemented through periodic sending of continuity 
check messages (CCMs) by the MEPs. As a multicast message, a CCM sent by one MEP is intended to 
be received by all the other MEPs in the same MA. If a MEP fails to receive the CCMs within 3.5 times 
the sending interval, the link is considered faulty and a log is generated. When...

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time, and calculates the link transmission delay and jitter according to the DMR reception time and 
DMM transmission time. DMM frames an d DMR frames are multicast frames.  
TST 
The TST function tests the bit errors between two MEPs. The source MEP sends a TST frame, which carries 
t h e  t e s t  p a t t e r n ,  s u c h  a s  p s e u d o  r a n d o m  b i t  s e q u e n c e  ( P R B S )  o r  a l l - z e r o ,  t o  t h e  t a r g e t  M E P.  U p o n  r e c e i v i n g  
the TST frame, the...

 21 
Tasks Remarks 
Configuring LM Optional 
Configuring one-way DM Optional 
Configuring two-way DM Optional 
Configuring TST Optional 
 
 NOTE: 
Typically, a port blocked by STP cannot receive or  send CFD messages except in the following cases: 
•   The port is configured as an outward-facing MEP.  
•   The port is configured as a MIP or inward-facin
g MEP, which can still receive and send CFD messages
except CCM messages.  
 
Configuring basic CFD settings 
Enabling CFD 
Enable CFD on all concerned...

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Configuring service instances 
Before configuring the MEPs and MIPs, you must first configure service instances. A service instance is a 
set of service access points (SAPs), and it belongs to an MA in an MD.  
A service instance is indicated by an integer to represent an MA in an MD. The MD and MA define the 
level and VLAN attribute of the messages handled by the MPs in a service instance. 
Service instances fall into two types: 
•   Service instance with the MD name, which  takes effect in any...

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Before creating MEPs, configure the MEP list. An MEP list is a collection of local MEPs allowed to be 
configured in an MA and the remote MEPs to be monitored. 
 
 IMPORTANT: 
You cannot create a MEP if the MEP ID is not incl
uded in the MEP list of the service instance.  
 
To  c o n fig u re  a  M E P :   
Step Command Remarks 
1.  Enter system view.  system-view  N/A 
2.  Configure a MEP list.  cfd meplist 
mep-list 
service-instance  instance-id  By default, no MEP list is 
configured.  
3....

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Step Command Remarks 
1.  Enter system view.  system-view  N/A 
2.  Configure the rules for 
generating MIPs.  cfd mip-rule 
{ explicit  | default  } 
service-instance  instance-id By default, neither MIPs nor the 
rules for generating MIPs are 
configured.  
 
Any of the following actions or cases can cause MIPs to be created or deleted after you have configured 
the 
cfd mip-rule  command: 
•   Enabling CFD (use the  cfd enable command) 
•   Creating or deleting the MEPs on a port 
•   Changes...

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Table 9 Relationship between the interval field value, the interval between CCM messages, and the 
timeout time of the remote MEP 
The interval field value  The interval between CCM 
messa
ges 
The timeout time of the remote 
MEP
 
4 
1 second  3.5 seconds 
5 10 second  35 seconds 
6 60 seconds  210 seconds 
7 600 seconds  2100 seconds 
 
Configuring LB on MEPs 
The LB function can verify the link state between the local MEP and the remote MEP or MIP. 
To configure LB on a MEP: 
 
Task Command...

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Configuring AIS 
The AIS function suppresses the number of error alarms reported by MEPs.  
To make an MEP in the service instance send AIS frames, you must configure the AIS frame transmission 
level to be higher than the MD level of the MEP.  
Enable AIS and configure the proper AIS frame transmission level on the target MEP, so the target MEP 
can suppress the error alarms and send the AIS frame to the MD of a higher level. If you enable AIS but 
do not configure the proper AIS frame transmission...

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To view the test result, use the display cfd dm one-way history command on the target MEP.  
To configure one-way DM: 
 
Step Command Remarks 
1.   Enter system view. 
system-view  N/A 
2.  Configure one-way 
DM.  cfd dm one-way service-instance 
instance-id
 mep mep-id  { target-mac 
mac-address |  target-mep 
target-mep-id  } [ number number ]  Disabled by default. 
The 
target-mep  target-mep-id  option is 
not supported if an outward-facing MEP 
is configured on the switch.  
 
Configuring...