10 common errors in virtualization

Virtualization has become one of the main technologies in many businesses. However, simplicity of deployment can bring many problems. Here are 10 common errors when virtualizing.

10. Virtualization on an old device

Microsoft Hyper-V and VMware ESX Server can be installed on the old platform. However, on platforms guaranteed by newer processors, functions such as Second Level Address Translation (SLAT) and Nested Page Tables (NPT) can significantly enhance virtualization and transfer performance. The care of the device during the translation of memory addresses in the guest virtual machine addresses the physical dynamic memory.

9. Install antivirus software on the virtual hard disk

The use of antivirus software is a good idea. However, antivirus software scans the virtual machine hard drive (VHD), which can reduce its performance. Make sure you disconnect the VHDs from the scan of the base system.

8. Skip backup of guest virtual machine

A copy of the virtual computer can be created on the host level (host) without having to stop the user's session and ensure a slight recovery after failures. But, even in this case, backup copies at the host level cannot be considered an alternative to the client system. Applications such as Microsoft SQL Server and SharePoint require a copy on the client system to protect user data.

7. Host security system is not suitable

People often focus on the client security system, but the organization of the server protection system is more important because the host has access to all client resources. The host needs a physical security system. Moreover, all the resources on it need to be protected according to the principle of minimum privilege.

6. Regularly use the default settings

Another common error is blindly accepting default settings. We often change the location of the proposed virtual computers by default, from DAS to SAN. However, you need to consider the processor, memory capacity and hard disk as well as the network diagram of the virtual machine so that they correspond to the specific virtual machine load.

5. Improper host uploader

Virtualization allows for higher device utilization rates than using physical servers. And nothing prevents the loading of processor base system load from a series of virtual machines. In the ideal case, be sure to separate a processor core for each virtual machine. The Windows Server Resource Monitor can give you a quick look at the load situation of the processor and its cores.

4. Inappropriate host memory capacity

Dynamic memory is the main limiting factor for simultaneous booting of several virtual machines because each virtual computer needs its memory from physical memory. Make sure you have the full amount of dynamic memory for the virtual computer in the host you are about to boot. In addition, there should be enough memory for host needs.

3. Lack of network cards on the host

Another common error, especially in projects that link servers (servers), is the number of network cards not enough for hosts. When linking servers, all network data traffic from virtual machines will go through the host's network cards. Maybe, you don't need network cards in 1 - 1 correlation, but data traffic from a large number of virtual machines will be easily overloaded due to the lack of network cards.

2. Too many virtual machines on the same cluster (Cluster Shared Volume)

CSV (Cluster Shared Volume) is a new feature in Windows Server 2008 that allows several virtual machines to use the same LUN (Logical Unit Number). By default, all virtual machines are directed to the same CSV. That may not be important for small downloads but with more serious downloads like SQL Server requires more CSV. In this regard, it should be noted that the performance of the disk system depends on the number of disks, so the use of external storage with a large number of disks will ensure higher performance.

1. Use only one CSV on a virtual machine

It is suggested that virtual machines are restricted using only one CSV. But you can not only create more than CSV numbers for a virtual server but also save your virtual server's VHD files on different CSVs. You can put the system files and swap files into a VHD on a number of CSV and put the data files and user data into a VHD file located on another CSV.