Each cluster has an associated security group that specifies the addresses from which the cluster will accept connections. By default, the security group exposes only port 9999 (the load balancing port) to the outside world, while allowing inter-cluster communication, and console-to-cluster communication between the servers in the cluster.You can modify the security group, strategically exposing other ports for client connection. For example, you may wish to open port 22 to allow ssh connections to a server, or port 5444 to allow connections to the listener port of the Advanced Server database server that resides on a replica node.EDB Ark assigns the same security group to every member of a cluster. By default, the security group contains rules that specify that any cluster member may connect to any other member's ICMP port, TCP port or UDP port. These rules do not permit connections from hosts on the public Internet. You must not alter these security rules.Additional rules open TCP ports 7800-7802 to the cluster manager, allowing the cluster manager to perform maintenance and administrative tasks. Please note that the rules governing connections from the cluster manager must remain open to allow:The rule for TCP port 9999 uses a CIDR mask (0.0.0.0/0) to specify that port 9999 is open for connections from any IP address. You can customize this rule, selectively restricting the IP addresses from which computers are allowed to connect to a given port within the cluster.