There’s, probably, no IT administrator who hasn’t heard of SMB3 (Server Message Block). is an application-layer network protocol, developed by Microsoft mostly to provide shared access to the files, and allowing communication between nodes. SMB has been designed as a tool for the creation of a DOS-based network file system, but Microsoft took the initiative and renamed SMB into CIFS later on (Common Internet File System) and continued further developing it. The second version – SMB 2.0, has been introduced in Windows Vista with a wide range of new features, thus it became clear that Microsoft was working hard to improve this protocol.

Howdy, folks! I would like to start my tale with a little backstory regarding usefulness which the “maintenance mode” brings to us. And in order to do that, I’ll start from the times when updates have led to the downtime for production. That’s not a secret for anyone that any production environment sometimes needs to be maintained. It could either be a software update or a hardware reconfiguration. To do this, the administrator should stop the production server for a certain period of time, and this may affect the reliability of the production environment. For example, the fault tolerance level can be decreased, as well as the performance. This is especially critical for small infrastructures which consist of 2 nodes.

Before we have started our journey through the storage world, I would like to begin with a side note on what is hyperconverged infrastructure and which problems this cool word combination really solves. Folks who already took the grip on hyperconvergence can just skip the first paragraph where I’ll describe HCI components plus a backstory about this tech. Hyperconverged infrastructure (HCI) is a term coined by two great guys: Steve Chambers and Forrester Research (at least Wiki said so). They’ve created this word combination in order to describe a fully software-defined IT infrastructure that is capable of virtualizing all the components of conventional ‘hardware-defined’ systems.