Internal building blocks of VSAN
Furthermore, there are internal components that work below the surface of VSAN. While an administrator may never have to deal with these components, a fair understanding of these components will help understand the internal workflow of VSAN and also to effectively troubleshoot issues.
We will discuss the following internal components of VSAN and how they work together:
Reliable datagram transport
Cluster monitoring, membership, and directory services
Cluster-level object manager
Distributed object manager
Local log structured object manager
Reliable datagram transport
The primary backbone for VSAN functionality is the VMkernel port group for VSAN traffic and reliable datagram transport (RDT) operates on top of the VSAN VMkernel network to enable communication channels between the nodes participating in the VSAN cluster. RDT is optimized to transmit large chunks of data; it can set up and tear down transport connections based on underlying link status.