What is “Network Ping Test IP”?

Upon creation of a cluster there is an option to enter network ping test ip...

This IP is used by the server to determine if the network is still available. Cluster nodes will ping this address constantly, if none of the IPs is available. The node will know that it is offline and will give its services to the online node

It is recommended to put more than just one IP.

This can be any device on your network that is constantly on, router, gateway, printer, mail server etc.. ..

Supported Guest Operating Systems

Following operating systems are supported and can be run as virtual machines (VMs) within euroNAS Enterprise Virtualisation OS (64-Bit versions only).

Microsoft Windows

In order to achieve the best possible performance Microsoft operating system require an additional paravirtualized driver to be installed during installation. Please click here for detailed instructions.

Guest OS Hardware acceleration Paravirtualized driver
Microsoft Windows Server 2019
Microsoft Windows Server 2016
Microsoft Windows Server 2012 R2
Microsoft Windows Server 2012
Microsoft Windows Server 2008 R2
Microsoft Windows Server 2008
Microsoft Windows 10
Microsoft Windows 8.1
Microsoft Windows 8
Microsoft Windows 7


euroNAS Premium R3 and HA Cluster R3 are natively supported by euroNAS Hypervizor. Previous versions are currently not supported.

Guest OS Hardware acceleration Paravirtualized driver
Premium Ultra R3
HA Cluster R3
Premium Ultra R3
HA Cluster R3


Following Linux based operating systems have been certified and work “out of the box” (drivers are built-in)

Guest OS Hardware acceleration Paravirtualized driver
Red Hat Enterprise Linux 7.x
Red Hat Enterprise Linux 6.x
CentOS 7.x
CentOS 6.x
Fedora Server 23
Fedora Workstation 23
Debian Jessie
Debian Wheezy
Ubuntu Server 14.04 LTS
Ubuntu Server 18.04 LTS
Ubuntu Server 20.04.1 LTS
Ubuntu Desktop 14.04 LTS
Ubuntu Desktop 15.10
Ubuntu Desktop 18
Ubuntu Desktop 20.04.1 LTS

How is Live Migration of running VMs working?

eEVOS helps you to migrate running virtual machines from one cluster node to another one without downtime.

VM will keep its connections, RAM and all settings will be moved. Whole migration takes just several seconds.

It is very useful functionality if you wish to shut down or reboot one of the nodes for maintenance or upgrade.

How do I create virtual machine?

VM Creation window contains 4 tabs. The mandatory settings for the VM creation are listed in “General Tab”.

The settings in all other tabs are optional. For settings adjustments you can use mouse or for fine tuning the arrow keys.

General tab

VM Name

Name for the new VM

Guest Operating System

Selection of the appropriate guest operating system makes sure that the VM is configured the most optimal way.

ISO Selection

You can select the installation CD for the installation of the Guest OS. Installation ISO must be copied on one of the VM drives. VM drives are accessable via SMB/CIFS and NFS shares.

CPU Selection

Select amount of CPU sockets and cores that you wish to assign to the VM.

VM Memory Size

Select amount of max memory that the VM is allowed to use. GUI will also show you the amount of memory that is currently assigned to all other VMs.

You can also overcommit memory however keep in mind that if all VMs try to use more memory than available that this could cause VMs to crash.

Cluster Drive

Drive that the VM will be installed on

Storage Type

You can select 2 storage types:
RAW – it provides best performance, reserves whole capacity immediately
QED – thin provisioned. Good performance uses spacy dynamically

Resource Size

Size of the VM disk. You can also add additional disks by clicking on Storage Tab and selecting the option Add More Drives. This can be also done later after VM creation.

Display Tab

VMs can be accessed using the embedded console or via VNC viewer. For the best performance and experience we recommend using remote access tools that are running within your VM. Most common is RDP protocol. That is part of all Windows versions and many Linux distributions. Other alternative is external tool such as Teamviewer or similar.

Password: you can password protect the access to individual VMs
Keyboard mapping: set which keyboard mapping the VNC client will be using
VNC Port: define which VNC port will be used for this VM.

Storage Tab

In storage tab you can attach ISO or add additional virtual disks to your VM.

Networking Tab

Under Networking tab you can define how many virtual networking cards you need and also to which hypervisor network they will belong. You can define different virtual NICs to belong to different virtual networks.

Installing the paravirtual drivers

The most modern Linux Distributions have already embedded paravirtual drivers. Those are ensuring the best possible performance and communication with the host OS. For Microsoft Windows Systems this drivers must be added during the installation.

This article describes the installation within Windows Server 2012, other versions are very similar.

Following drivers must be installed:
- Memory driver - Disk driver - Network driver - VSS Communication port (important for the live snapshots)

1. After creation of the Windows VM the installation will begin. Initially no installation drives will be listed before you install the driver manually.

Select the Option Load Driver

2. Select browse

3. Select CD Drive Virtual Drivers

4. Select the folder Disk Driver and the subfolder for your windows version.
For example 2k8 = Windows 2008

5. Your virtual disk will be now shown properly and you can continue with the installation. After the installation of the OS you can install the other drivers within the device manager.(check #6)

6. After the successful installation please go to Device Manager and install the remaining drivers.

Ethernet=Network Driver PCI Device=Memory Driver PCI Simple Communications Controller = VSS Communication driver

Click with the right mouse button and select Update Driver Software ...

7. Select Browse my computer for driver software.

8. Select the folder that contains the driver (here for example network driver) and your windows version.

For example 2k8 = Windows 2008

9. Select install

10. Repeat the procedure for all remaining devices

Virtual Network for the virtual machines

Virtual Machines can use 2 different types of virtual Network.

You can create several virtual networks and also assign them to different virtual network ports.


Bridge is directly attached to one or several network ports. Through the bridge the virtual machines will get the direct access to the network.


This mode creates a virtual network that will capsule virtual machines into their own virtual network. They will communicate with each other and also have access to the outside world

NAT network can also provide a DHCP services for the VMs

On VM creation or edit you can then assign the networks to individual NICs.

How is eEVOS Plus licensed?

eEVOS Plus is licensed per CPU (unlimited cores).

Smallest license would be 1 CPU which allows installation on one server.

For the high availability at least 2 CPU licenses are required (one CPU per node).

Licenses must be kept in pairs and the amount of the CPUs must be the same on each individual node.

4 CPU license allows either 4 CPU single server or 2 Servers with 2 CPUs.

You can use motherboard with several CPU sockets – as long as these are not populated you will not be asked for additional license. This way you can later install additional CPUs and upgrade your license.

Can I assign more than one virtual network to individual VM?

On VM creation or edit you can assign different networks to each individual virtual NIC.

My OS is not on the compatibility list

eEVOS compatibility list contains the list of all tested and certified operating systems

However there is a wide range of compatible operating systems not mentioned on our list. For the installation of these operating systems please choose during the install the option “other” – you will get following modes

Virtio Mode

Virtio Mode uses paravirtualized drivers providing best performance – it is already embedded in the most modern Linux Distributions (for not listed windows versions please use compatibility mode or test it with some other windows version listed during the VM creation).

Compatibility Mode

This mode emulates standard hardware which most operating systems support “out of the box”. For example “Intel Gigabit Network Controller”.

Can I watch VM Usage in Realtime?

Unter VM Overview Tab there is a button “VM Stats”. This one will dynamically show the VM ressource usage.(updates every 5 seconds). By clicking on the name (for example CPU%) it will sort the VMs according to the usage.

RDRQ = Read Requests (Virtual Disk)
WRRQ = Write Requests (Virtual Disk)
RXBY = Received Bytes (Network)
TXBY = Transferred Bytes (Network)
CPU Usage in %
Memory usage in %
TIME = Uptime in hours
NAME = VM Name

In this example we have 4 VM running (2 per each node).