Continuity Check Messages - Dell S4048–ON Configuration Manual

MP ID: 900
Sender Chassis ID: Force10
MEP Interface status: Up
MEP Port status: Forwarding
Receive RDI: FALSE
MP Status: Active
Setting the MP Database Persistence
To set the database persistence, use the following command.
• Set the amount of time that data from a missing MEP is kept in the continuity check database.
ECFM DOMAIN
database hold-time minutes
The default is 100 minutes.
The range is from 100 to 65535 minutes.

Continuity Check Messages

Continuity check messages (CCM) are periodic hellos.
Continuity check messages:
• discover MEPs and MIPs within a maintenance domain
• detect loss of connectivity between MEPs
• detect misconfiguration, such as VLAN ID mismatch between MEPs
• detect unauthorized MEPs in a maintenance domain
CCMs are multicast Ethernet frames sent at regular intervals from each MEP. They have a destination address based on the MD
level (01:80:C2:00:00:3X where X is the MD level of the transmitting MEP from 0 to 7). All MEPs must listen to these multicast MAC
addresses and process these messages. MIPs may optionally process the CCM messages the MEPs originate and construct a MIP
CCM database.
MEPs and MIPs filter CCMs from higher and lower domain levels as described in the following table.
Table 7. Continuity Check Message Processing
Frames at
Less than my level
My level
My level
Greater than my level
All the remote MEPs in the maintenance domain are defined on each MEP. Each MEP then expects a periodic CCM from the
configured list of MEPs. A connectivity failure is then defined as:
• Loss of three consecutive CCMs from any of the remote MEP, which indicates a network failure.
• Reception of a CCM with an incorrect CCM transmission interval, which indicates a configuration error.
• Reception of a CCM with an incorrect MEP ID or MAID, which indicates a configuration or cross-connect error. This error could
happen when different VLANs are cross-connected due to a configuration error.
Frames from
Bridge-relay side or Wire
side
Bridge-relay side
Wire side
Bridge-relay side or Wire
side
UP-MEP Action
Drop
Consume
Drop
Forward
Down-MEP Action
Drop
Drop
Consume
Forward
MIP Action
Drop
Add to MIP-DB and
forward
add to MIP-DB and
forward
Forward
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