[HDDS-2823] SCM HA support (implementing)

Authors: Li Cheng, Nandakumar Vadivelu, Rui Wang, Glen Geng, Shashikant Banerjee

2020-03-05

Summary

HA for Storage Container Manager using Ratis to replicate data

Abstract

Proposal to implement HA similar to the OM HA: Using Apache Ratis to propagate the

The main SCM HA design doc is available from here

During the implementation of SCM-HA many smaller design docs are created specific to various areas:

SCM HA Distributed Sequence ID Generator: about generating unique identifier across multiple nodes of the HA quorum
SCM HA Service Manager: about starting and stopping the main SCM services (like PipelienManager, ReplicationManager) in case of a failover
SCM HA SCMContext: about using a helper object which includes all the key information for all the required service components
SCM HA Snapshots: about RAFT state-machine snapshots
SCM HA: DeleteBlockLog: about coordinating block deletions in HA environment
SCM HA: bootstrap: about initializing the SCM HA cluster