The storage systems support load balancing within a controller and between controllers.

• Load balancing within a controller: At the transmit end, all the replication links that belong to the same controller have almost the same transmission bandwidth.

  For example, HyperMetro is established between storage arrays A (local) and B (remote) and the total transmission bandwidth is 200 MB/s. Controller A on array A has two replication links, link 0 and link 1.

• If load balancing within controller A is enabled, link 0 and link 1 each has 100 MB/s bandwidth.

• If load balancing within controller A is disabled, the bandwidth of link 0 is 200 MB/s and that of link 1 is 0 MB/s.

Load balancing between controllers: If the bandwidth usage of a controller at the transmit end exceeds 50% of the total bandwidth, services are switched over to the other controller for load balancing.

For example, HyperMetro is established between storage arrays A (local) and B (remote) and the total transmission bandwidth is 200 MB/s. Controller A on array A has one replication link (link 0), while controller B has one replication link (link 256).

• If load balancing between the controllers is enabled, link 0 and link 256 each has 100 MB/s bandwidth.

• If load balancing between the controllers is disabled, the link on the working controller of HyperMetro occupies the entire 200 MB/s bandwidth. If both are working controllers, each controller carries services on its own link independently.

Load balancing within a controller is enabled by default for HyperMetro and cannot be modified by users.