VMmanager 6: Administrator guide

Server requirements for the cluster

A cluster is a group of servers in a single location. The key feature of such servers (cluster nodes) is their location and high data transfer speed between them. A cluster node must meet the following requirements. 

Homogeneity of nodes

We recommend using nodes in one cluster, which are homogeneous in their network settings, routing, software versions. This will provide the optimal conditions for virtual machine migration between cluster nodes.

Virtualization support 

Use a physical server that supports processor virtualization. Execute the command to check the support for Intel and AMD processors:

grep -P 'vmx|svm' /proc/cpuinfo

If the command output is not empty, the processor supports the virtualization.

To be able to use the virtualization check that it is enabled in the server BIOS.

Hardware requirements

Server characteristics: 

CPU3 GHz> 3 GHz
RAM8 Gb16 Gb
Disk space1 Tbyte2 Tbyte

Your server must have access to the Internet and a public static IP address.


The IP address must be added to the server physical interface.

Check that network bridges are not created on the server. 

The server disk is used to store virtual machines, their images, and operating systems: 

  • /vm for virtual machines;
  • /images for images;
  • /share for operating systems.

We recommend that you allocate the main disk volume to the root directory.

System requirements

The supported operating system is CentOS 7 x64 or CentOS 8 x64. We recommend a clean install of the operating system without third-party repositories and additional services. Minor OS versions and OS kernel versions on the cluster nodes may be different.


Each server in the cluster must have a unique hostname.


For servers from the data center OVH, enable the option Install original kernel when deploying an operating system from the control panel OVH.

Network settings

Allow incoming connections to ports:

  • 22/tcp — SSH service;
  • 5900-6900/tcp — QEMU VNC. If access to VNC is only provided through the server with VMmanager, the range of ports must be open for the network integrating the cluster nodes;
  • 16514/tcp — libvirt virtual machines management service;
  • 49152-49261/tcp — libvirt migration services.