SSR Cluster Configurations Overview
For the highest level of redundancy, each data node must run on its own C Series Controller. Each C Series Controller configured as a client node supports the SSR client components and at least one client node must be configured to host the management server. The management server can run only on a client node. Separation is required so that management arbitration services continue if one of the data node fails. However, for full redundancy, two client nodes should be configured to host management servers.
Using these separation guidelines, we recommend a minimum SSR cluster size of:
Two client nodes, each running an instance of the management server and a client component
Two data nodes, each running on its own C Series Controller
This configuration is shown in Figure 1:
For small-scale deployments, the minimum SSR configuration requires three C Series Controllers set up in the two-shared-data-node geometry. In this configuration, there are two data-client-nodes and two management servers. One management server must be running on the third C Series Controller and the other one can reside on any data-client-node. You also need to run redundant SAEs, SICs, and other components such as NIC to maintain redundancy. Each C Series Controller acts as a backup for the other. This solution requires you to configure the data node memory size because memory is shared with other components.