Cluster Controller (CC)
The Cluster Controller (CC) is written in C and acts as the front end for a cluster within a Eucalyptus cloud and communicates with the Storage Controller (SC) and Node Controller (NC). The CC manages instance (i.e., virtual machines) execution and Service Level Agreements (SLAs) per cluster.
Storage Controller (SC)
The Storage Controller (SC) is written in Java and is the Eucalyptus equivalent to AWS Elastic Block Store (EBS). The SC communicates with the Cluster Controller (CC) and Node Controller (NC) within the distributed cloud architecture and manages Eucalyptus block volumes and snapshots to the instances within its specific cluster. If an instance requires writing persistent data to memory outside of the cluster, it would need to write to Walrus, which is available to any instance in any cluster. The SC interfaces with storage systems, including local, NFS, iSCSI, and SAN.
VMware Broker (Optional)
The VMware Broker is an optional component that provides an AWS-compatible interface for VMware environments and physically runs on the Cluster Controller (CC) within the distributed cloud computing architecture. The VMware Broker overlays existing ESX/ESXi hosts and transforms Eucalyptus Machine Images (EMIs) to VMware virtual disks. The VMware Broker mediates interactions between the CC and VMware and can connect directly to either ESX/ESXi hosts or to vCenter Server.