Which port is used for full synchronization between cluster members in the Firewall Kernel?

In a Check Point cluster, full synchronization between cluster members occurs over TCP port 256. This port is specifically designated for the synchronization of the state information and configuration data among the cluster nodes. This process ensures that all members of the cluster maintain consistent state information and configuration, which is critical for redundancy and failover functionality.

Using TCP for this communication is important because TCP provides reliability and ensures that data packets are delivered in the correct order without loss. This is essential for maintaining the integrity of the cluster's operational data. The synchronization process involves sending a substantial amount of state information, which benefits from the connection-oriented nature of TCP.

In contrast, the other options provided involve UDP, a connectionless protocol that does not guarantee delivery or order. While UDP may be suitable for other types of communications that can tolerate packet loss or out-of-order messages, it is not utilized for the crucial task of full synchronization in Check Point clusters, where data integrity is paramount.