MC-LAG Clustering HA: Key Points for Cisco CCIE Service Provider Exam

MC-LAG Clustering HA

Question

In the MC-LAG environment, which two statements about clustering HA are true? (Choose two.)

Answers

Explanations

Click on the arrows to vote for the correct answer

A. B. C. D. E.

AB.

In a MC-LAG (Multi-Chassis Link Aggregation Group) environment, clustering HA (High Availability) is used to ensure that the network remains highly available even in the event of a failure of one of the nodes in the cluster. Clustering HA is achieved by grouping two or more nodes together into a cluster, where one node acts as the active node and the other nodes act as standby nodes. The active node processes traffic while the standby nodes are idle, waiting for the active node to fail.

Regarding the statements given in the question, the correct answers are A and C. Let's explain why:

A. Private connection is used to connect the nodes of the cluster for private communication: In a clustering HA configuration, the nodes in the cluster must communicate with each other to ensure that the active node is processing traffic and that the standby nodes are ready to take over if the active node fails. This communication is done through a private connection, which is used for cluster control traffic. The private connection is usually a dedicated connection between the nodes of the cluster and is not accessible from outside the cluster.

B. Public connection is used to access the active node of the cluster from the outside cluster: This statement is incorrect. The public connection is used for external traffic and is not used to access the active node of the cluster. Access to the active node is controlled by the private connection.

C. Public connection is used to monitor the health and status of each node in the HA cluster using the heartbeat system: In a clustering HA configuration, the nodes in the cluster must constantly monitor each other's health and status to ensure that the active node is processing traffic and that the standby nodes are ready to take over if the active node fails. This is done through a heartbeat system, which sends periodic messages between the nodes of the cluster. The heartbeat system uses the public connection to monitor the health and status of each node in the HA cluster.

D. Private connection is used to access the active node of the cluster from the outside cluster: This statement is incorrect. Access to the active node is controlled by the private connection and is not accessible from outside the cluster.

E. Public connection is used to connect the nodes of the cluster for private communication: This statement is incorrect. The public connection is used for external traffic, while the private connection is used for cluster control traffic between the nodes in the cluster.