Educational Episodes: Hyperconverged Infrastructure (HCI)

Warning: This article is written with information related to Windows Server 2016 Technical Preview 4. Storage Replica is a new feature introduced in Windows Server 2016 that enables storage-agnostic, block-level, synchronous replication between servers for disaster recovery, as well as stretching of a failover cluster for high availability. Synchronous replication enables mirroring of data in physical sites with crash-consistent volumes ensuring zero data loss at the file system level. Asynchronous replication allows site extension beyond metropolitan ranges with the possibility of data loss.

Microsoft released the last version of the Nano Server, Technical Preview 4. They released the TP4 of System Center too. with this last version, SCOM has the ability to monitor a Nano Server.

MSI package are useful to be deployed in centralized management environment of Microsoft Active Directory. Unfortunately to deploy a software you need a MSI package. Microsoft do not support deploying EXE applications via GPOs. So if your organization has some of those EXE applications and want do manage the deployment via Group policy, it’s necessary to repackage the EXE and create an MSI package.

In this article, I will explain to you how to change the subnet of a Virtual Machine in Azure. Following is the official documentation on the Microsoft Website this documentation.

This is a short summary on Storage Spaces Direct – the first true software-defined storage from Microsoft, its history and peculiarities. Software-defined storage is a concept, which involves storing data without dedicated hardware. This is an introduction to a series of posts dedicated to theoretical and practical research of S2D. The post is not a full description of the Storage Spaces Direct technology, more info is available on Microsoft resources. Our focus here is the actual problem that S2D solved for virtualization world, being truly independent from underlying hardware, as SDS should. Its predecessor, Clustered Storage Spaces, had a very serious hardware lock-in with its requirements for SAS fabrics, SAS switches and SAS JBODS. Thus, Storage Spaces Direct is an interesting technology to research.

Log-Structured File System is obviously effective, but not for everyone. As the “benefits vs. drawbacks” list shows, Log-Structuring is oriented on virtualization workload with lots of random writes, where it performs like a marvel. It won’t work out as a common file system for everyday tasks. Check out this overview and see what LSFS is all about.

The post describes the history of RAID 5 and how it became obsolete at some point in time, just because HDD capacity grew at an enormous rate. It happened due to the chance of failure that grew to literal imminence when spinning disks reached TB scale, because the reading speed still had the same physical limits. Basically, creating a RAID 5 even with 1 TB disks would mean certain failure of the whole array and quite soon. The array technology was “saved” by an unlikely ally – the SSD. Being faster than hard disk drives in everything, they almost nullify the chance of the abovementioned failures. The post is written for everyday reader, not just engineers, and is quite comprehensive even without special knowledge and skills.

Here is a comparison of two technologies with similar task but different methods of accomplishing it – Link Aggregation Control Protocol (LACP) and Multipath I/O (MPIO). Both are aimed at providing higher throughput when one connection can’t handle the task. To achieve that, LACP bundles several physical ports into a single logical channel. MPIO, on the other hand, utilizes more than one physical path, even if the working application does not support more than one connection. Both technologies seem to be equally effective at first glance, but further study confirms that one of them is better at achieving its goal. The post is practical, so expect detailed research with screenshots and complete analysis of the technologies in a test case.

This research is, basically, an answer to some statements about NFS shares and Hyper-V Virtual Machines that StarWind engineers considered false. Hyper-V is a native hypervisor from Microsoft and one of the most popular ones. It is capable of creating virtual machines on x86 and x64 Windows systems. Microsoft suggests that VMs should be stored in the Cluster Shared Volumes, in case live migration and failover are required. Storing them on an NFS share was never present in the design, so StarWind team was a bit skeptical about the idea at the first place. This research contains the full experiment, aimed at proving or disproving the initial statement, complete with a few different checks. The result is quite an expected one, but nevertheless, curiosity is strong in StarWind engineers.