Cisco Cisco ASR 5000
one PMIPv6 session with a corresponding LMA. Similarly, the LMA also initiates a heartbeat exchange with
the MAG by sending a Heartbeat Request message to check if the MAG is reachable.
the MAG by sending a Heartbeat Request message to check if the MAG is reachable.
Figure 11: MAG and LMA exchange Heartbeat messages
Refer to the heartbeat CLI command in the LMA Service mode or MAG Service mode respectively to enable
this heartbeat and configure the heartbeat variables.
this heartbeat and configure the heartbeat variables.
The heartbeat messages are used only for checking reachability between the MAG and the LMA. They do
not carry information that is useful for eavesdroppers on the path. Therefore, confidentiality protection is not
required.
not carry information that is useful for eavesdroppers on the path. Therefore, confidentiality protection is not
required.
Failure Detection
The sequence number sent in the Heartbeat Request message is matched when the Heartbeat response is
received at the MAG/LMA. Before sending the next Heartbeat Request, the missing heartbeat counter is
incremented if it has not received a Heartbeat Response for the previous request.
received at the MAG/LMA. Before sending the next Heartbeat Request, the missing heartbeat counter is
incremented if it has not received a Heartbeat Response for the previous request.
When the missing heartbeat counter exceeds the configurable parameter max-heartbeat-retransmission, the
MAG/LMA concludes that the peer is not reachable. The heartbeat request to the peer will be stopped and a
notification trap is triggered to indicate the failure.
MAG/LMA concludes that the peer is not reachable. The heartbeat request to the peer will be stopped and a
notification trap is triggered to indicate the failure.
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PMIPv6 Heartbeat
Failure Detection