Final answer:
Servers in an NLB cluster should have two NICs to handle user traffic and internal cluster operations separately, ensuring improved performance, redundancy, and security. Dual NICs help in balancing the network load and preventing a single point of failure.
Step-by-step explanation:
The configuration of Network Load Balancing (NLB) clusters with two Network Interface Cards (NICs) can provide distinct advantages. One of the main reasons for this configuration is to enhance both the performance and reliability of the server cluster. Having multiple NICs allows one to be dedicated to handling user traffic while the other manages internal cluster operations such as inter-node communication, which is essential for maintaining cluster health and synchronization.
Another reason for utilizing dual NICs is redundancy. If one NIC fails, the other can continue to operate, reducing the risk of downtime. This setup can also improve security, as traffic types can be segregated; one NIC can be exposed to a public network while the other operates on a secure, private network.
Frequently, when configuring an NLB cluster, traffic is distributed among the servers based on the destination IP address and port number of the incoming packets. By using two NICs, you can ensure that high volumes of network traffic do not overwhelm a single card, which could lead to performance bottlenecks or service interruptions.