In this post, I’d like to discuss data consistency – an important thing when it comes to backups. If data is consistent, it can be used across your environment, so you can spin up applications faster after restoring from such backup. Actually, it’s why I think this topic to be so important even now.

Some time ago, I published articles on setting up a home lab using a PC running ESXi and Workstation. We all know that nested virtualization is not an ESXi-only feature; Microsoft Hyper-V also enables us to run VMs inside its VMs. Microsoft’s implementation of this technology is a bit different, but it exists. And, considering that VMware and Microsoft have been competing for a long time, it’s interesting to see what each has to offer for this type of virtualization. In this post, I examine how easy it is to configure a nested virtualization layer inside Hyper-V and vSphere VMs and discuss peculiarities of this process in both environments.

As an admin, I often have to deal with the necessity to transfer large OVF and ISO files or even move virtual machines (VMs) between ESXi hosts that have poor network performance or disposed in different locations with no network connection whatsoever. If a case like this occurs, a USB flash drive or USB external drive is a way to go. More specifically, you can use a drive in two different ways (by the way, both authors have my most sincere regards and appreciation for presenting these methods in a most coherent and simultaneously simple way). The first one is to copy files from a USB device to a host directly through SSH session without changing drive format as the following article suggests. However, such an approach has some issues, the most tedious one being maximum file size limitations, which certainly limits its use for larger files. You cannot work with the Graphical user interface (GUI) as well. Instead, you gotta use SSH and dive deep into the host data storage system, so you can figure I am a much bigger fan of a second way: creating a VMFS datastore on a USB drive. You can connect it to ESXi hosts and transfer files from one to another (or just store a temporary copy on an external storage device).

As the name of this article is hinting, I’m going to discuss the answers to the said questions. My beginner colleagues are often wondering what virtual disk is preferable to choose. Therefore, although I was talking about this topic a while ago here and there, it’s time to get to the point.

Last year, my colleague asked me for advice. He couldn’t add an iSCSI target, provided by AWS Storage Gateway, on VMware ESXi cluster. So, initially, this material was intended to serve as a manual. However, since I got a similar question once more just recently, I realized that this topic could be interesting to the others as well, which is why I decided to share this guide, hoping it will be useful.

There are always several reasons to move on from your existing infrastructure. Some admins are pursuing recent versions of familiar products. Some, on the other hand, just want to get rid of the bugs they already learned to live with but would rather not. Others are attracted by promises to increase the performance of their environment. Finally, everybody wishes to go with the times and use the latest software. Whatever the reason, we all eventually come in terms with the necessity to upgrade the infrastructure to the most recent version.

As the title is speaking for itself, it is quite clear that today, I am going to discuss various methods to open and close firewall ports on ESXi hosts. It is useless to consider whether configuring firewall rules is harmful or not since every admin once in a while meets the necessity of fine-tuning network to distribute access rights. So, you ought to know all the tools at your disposal one way or another.

Every admin knows a few tricks to find a short way when testing your VMs. Some of them are neat, and some aren’t, such as snapshots. Disk Mode in VMware ESXI allows you to replace this technology with a safe alternative!

As any other admin, you know that the VMs eventually start to suffer from disruptions, performance problems, or simply stop responding. That is a fact of life, unfortunately. Chances are, as a virtualization engineer, you’ve probably already met these problems at least once. And since the virtualized environment is quite a complicated system, there can be too many different reasons or factors that impact poor VM performance. Trying to find out what is wrong can take a lot of your time.