Tag: PowerShell

Hot adding/removing memory in Hyper-V 2016: a closer look at the feature

Today, I’ll talk about a thing that any sysadmin running Hyper-V VMs does (or still dreams about) while managing infrastructure resources: hot modifying assigned to VM memory amount. I’ll discuss not only the feature itself but also how it works on different OS and its impact on the environment stability.

All of us keep an eye on resource consumption within our environments. If a VM needs extra RAM to have the job done, we provide it with some, right? And, we usually run many VMs on our servers each with own purpose and configuration. That’s, actually, why changing the amount of assigned to a VM memory without rebooting it may come in handy. Also, many guys run some parts of their environments on Windows while having other parts run on something from Linux family. Looks pretty hectic in terms of management, doesn’t it?

The idea Behind Node Fairness in Hyper-V: How it works and why you need it?

For quite a long time, System Center Virtual Machine Manager (SCVMM) has a feature called Dynamic Optimization. Its main goal is to automatically rebalance VMs between the participating cluster nodes in case the placement is unequal. Now, this feature has partially became available in Windows Server 2016 in the form of Node Fairness. It balances the workloads among the hosts in a Hyper-V Failover Cluster and automatically live migrates guests from an overloaded node to  a less busy one with zero downtime.

Node Fairness goes embedded in Windows Server 2016 and is intended for deployments without SCVMM. SCVMM Dynamic Optimization delivers more versatile functionality than Node Fairness. Regarding this fact, Dynamic Optimization is recommended for balancing workloads among the cluster hosts. However, to use this feature, you need an additional license from the main operating system.

Now that we know what Node Fairness is, let’s take a look at how this service works.

How Can I Replace a Failed Physical Disk on Storage Spaces Direct in Windows Server 2016?

So, we all know about Microsoft’s Storage Spaces Direct (S2D to put it simple) by now. It’s the feature introduced in Microsoft Server 2016 (Datacenter Edition) that pools together server’s storage allowing to build…that’s right: highly available and easily scalable software-defined storage systems. In this article, I’m gonna talk about not as much about its fault-tolerance characteristics themselves, but some hands-on experience, namely: how to replace a failed disk.