What's the relationship between FusionStorage components?

Hello,  Asjad!

Have a nice day!

Matedata controller(DMC): the metadata control compent of FusionStorage for controlling distributed cluster status, data distribution rules, and rebuilding rules; MDC processes are deployed on zookeeper disks on three nodes to form an MDC cluster.

VBS(Virtual Block System): deployed on all nodes as a VBS cluster to manage volume metadata and provide the distributed cluster access point service, enabling computing resources to access distributed storage resources; Multiple VBS processes can run on one node to improve the node I/O performance.

OSD(Object Storage Device): deployed for each disk on all servers to perform specific I/O operations; One server can have multiple OSD processes deployed. When SSD cards are used as the main storage, multiple OSD processes can be deployed on one SSD card to maximize the SSD card usage and performance. For example, one 2.4 TB SSD card supports a maximum of six OSD processes, each of which manages the I/O operations for 400GB space.

Hope can help you!

In FusionStorage, MDC is the client of ZooKeeper. The number of ZooKeeper disks must be the same as that of ZooKeeper disks. The master selection mechanism of ZooKeeper determines that the number of ZooKeeper disks can only be an odd number, usually three or five, which is determined by the cluster size (that is, the number of managed OSDs). In the current FusionStorage cluster, three MDC disks are enough. Therefore, three MDC and three ZooKeeper disks are configured unless otherwise specified.