Hetzner - DokuWiki



What kind of virtualization is used?

The virtualization we use is based on KVM. We offer fully virtualized root servers.

Are there are any limitations?

As KVM is used for virtualization, there are no technical limitations on the number of processes or open files. It is thus possible to make changes to iptables and routing, and to install your own services. It it also possible to install a custom kernel.

How high is the performance of the vCPUs?

Each vCPU has the CPU performance of an Intel Xeon E5 CPU running at 2.0 GHz. The actual speed displayed in the instance may vary.

Which virtual network card is used?

By default, the virtual servers come configured with the "virtio" network card. It provides the best performance, but may not be compatible with every operating system. If required, you can change the model at any time via the Robot. Please note that you need to stop and then restart your virtual server to accept the change.


There are, as can be seen in the screenshot, the following models to choose from:

  • Realtek 8139
  • Intel E1000
  • VirtIO (recommended: offers the best performance, usually requires manual driver installation)

Important: Please make sure that the correct driver for this card has already been installed on the server, so that you can continue to have network access after the changeover. Not all operating systems provide by default a suitable driver.

For Windows systems: The drivers for VirtIO can be mounted and installed for example, via an ISO image. For more information see: Is it possible to mount ISO files?.

Is it possible to mount ISO files?

The mounting of CD/DVD images is possible via the Robot. To do this, select your virtual server, go to "vServer" -> "Settings" and select the required ISO image next to "Mount CD/DVD image". Once selected, click on "Save". The image is now mounted on your server and is ready for us. By selecting "-" the image can be ejected again.

Uploading custom ISOs is currently not possible but can be checked in individual cases by the support. Please contact the support to ask about this via the Robot.

The available images are constantly being updated. Please see this page for a complete list

Are there any automated backups?

We do not make automatic backups of the virtual servers, the client is responsible for that themselves. We offer backup space that can be used for this purpose. Please see: Backup

In addition, all CX servers have the ability to create a snapshot of the entire server, which can then be used to restore the server to that state.

Is it possible to automatically switch between different models?

With the CX models, clients can automatically upgrade from a smaller model to a larger one via the Robot webinterface. After that you need to resize the filesystem: Resize partition

Clients moving from an older VQ or VX model to a new CX model can migrate VQ/VX server as described in article vServer migration.

The same applies to clients wanting to downgrade from a larger CX model to a smaller CX model. The technical background is, that shrinking harddisks could cause dataloss.

Is it possible to order additional IPs, failover IPs or subnets?

Currently it is not possible to order additional IPv4 addresses.

Is IPv6 available?

Yes, in addition to the main IPv4 address, all servers also have a /64 IPv6 subnet.

For clients who received their servers before February 2013 this subnet can be ordered (freely) via Robot, and will be automatically activated.

Which operating systems can be installed?

The same images which are available on the dedicated servers are also available for the virtual servers. You can choose between different linux distributions as well as FreeBSD and Windows. It is also possible to install your own OS using our installimage.

How can an operating system be installed?

For the installation of an operating system on the server you can use our Rescue Systems (Linux or FreeBSD), or a VNC installation.

Is there any way to get an individual configuration?

Customized virtual servers (additional RAM, additional/larger drives etc.) are not currently possible.

Are tun/tap devices usable?

Yes they are usable. If you wanted to run openVPN for example, you could.

In which geographical location are the servers located?

All virtual servers are currently located in the data center park in Falkenstein (Vogtland). The uplink is connected through DC17.


The virtual disks of the virtual servers are located on a distributed SSD-based storage system. The data is redundantly saved 3 times, and is available even in the event of multiple system failures.

Therefore, the chance of data loss is very low. Please note however, that you are still responsible for your data, and Hetzner does not provide any guarantee for potential loss of data.

Each server can, if necessary, be started on a different machine, or migrated there. The assignment of virtual server to host system can change at any time due to load distribution mechanisms or maintenance, so the location in Robot is simply stated as being in a specific "vpool" (e.g. vpool0).

Why does my VM have the IP

Or also:

Why does my VM have a different IP from the one shown in the Robot?

Why does my VM have a private IP?

With the CX models the IPv4 address of the virtual server is a private IP, which is configured 1:1 via NAT on the public IP. Currently the private IP is the same for all: The public IP is displayed in the Robot.

Which network configuration must be done?

With an automatic installation, all the necessary changes have already been made for you and you can use the server right away.

With a custom installation, you need to change the network configuration yourself.

Change your network configuration (IPv4) as follows:

Static IP Address:
Default gateway:

The values for the IPv6 configuration can be found in the Robot.

How do I configure the DNS settings in Plesk?

The wiki page on Plesk has a guide for this.

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