How do you bill virtual servers?
When you create a new virtual server you can choose desired configuration and agree with price without VAT. Billing is done on hourly basis, time granularity is also one hour. It is billed from server creation till server removal, even if it is shut down. Each commenced hour your virtual's hourly price is deducted from the credit.
How do I charge my credit deposit?
Log in and use menu item My Account > Credit , choose payment method and amount. You will get payment proposal by e-mail. Your account will be charged few minutes after payment reception. You will get credit invoice by e-mail.
Do I have to request a new payment proposal each time?
No. You can use the same variable symbol more than once. Amount may be different. After payment reception your account will be credited immediately and you will get receipt by e-mail.
Can I pay credit by a standing order?
Yes, you can enter the same billing information. As a customer you are identified by variable symbol. Immediately upon receipt of payment you will be sent information about accepted payment and tax receipt.
Can I pay by credit card?
Yes, credit card payments are possible via PayPal . The advantage of credit card payments through PayPal is that you do not provide information about your card directly to the trader, but you always confirm payment of a specific amount to a specific subject. Virtualmaster thus never come into contact with your card information.
Do you offer some subscription plan?
Individual subscription plan is only possible for corporate customers. If you wish to become our corporate customer, please contact for more information.
When will I get invoice - tax receipt?
If you are registered in Czech Republic, you will be sent credit invoice - tax receipt immediately upon receipt of payment. Every customer will get monthly bill. Bill will have amount to be paid zero.
What happens if my credit falls bellow zero?
When your credit falls below pre-set level (default setting is 200 CZK, you can change this in menu Other > Settings > Other settings ), you will be notified about low credit level each day. When your credit falls bellow zero, all your servers will be shut down and their level will be lowered to "testing". Please be aware, "testing" does not include backup service. Your backups may be removed. In case you will not charge your credit your servers will be removed after expiration period (14 days). You will have to change server level manually, otherwise expiration period will apply and remaining servers in level "testing" will be removed.
When I run out of credit, are my servers billed, even they are stopped?
If you are low on credit and all of your servers are stopped, all of your instances are billed as usual. If you don't want to pay for stopped instances, please remove them.
Is it mandatory to pay negative credit?
Yes. Negative credit deposit is automatically subtracted from next payment.
Where can I find a copy of the invoice?
All of your invoices are available after sign-in in PDF format here My account > Ibnvo
How much time will creating of virtual server take?

Virtual servers are usualy created in several minutes.

Can I try before I pay?

Yes, it is possible, but only in the level "testing" and within its limits.

Testing of the service to the greater extent (multiple virtual servers, larger capacity and so on) is possible for free under an agreement with a support representative. Advanced testing can not be anonymous, that is, you must have a credit on your account or have the profile filled with valid data including phone number. We will also ask you to provide us with a brief information about your project.


What linux distributions are available?

You can choose from prepared images of following distros Debian GNU/Linux CentOS, Ubuntu, Fedora, Gentoo. The list of images is constantly growing. Any user can create an image with needed distribution and initial configuration, which can be then shared with other users or kept private. All available images are here: Virtualmaster Images.

What is the Virtual Private Server (VPS)?

Virtual private server is a method of splitting a physical server's resources . Virtual server shares resources with parallel VPSes. The communication between VPSes and hardware is managed by Hypervizor (XEN).

How do you peform backups?

Backup is provided for virtual servers in level "production". After server creation, you will get e-mail with instructions how to access backup repository. Backup repository is accessible via SFTP protocol.

We use reverse incremental backup scheme of rdiff-backup tool. Backup is performed usually during night between 1am and 7am CET/CEST timezone. Backup target is located on different physical node than your virtual server.

Reverse backup scheme means that you have direct access to files from last backup. If you need to restore some file(s) from older versions, you have to download/mount whole repository and perform restore using rdiff-backup tool, which applies increments automatically. You may also ask support to restore some paths of some date.

What is server image?

Image of virtual server system is just compressed blockdevice with filesystem with preinstalled operation system, ready to be used to create new instance. Our images includes tool called virtualmaster-firstboot, which takes care of automatical setup of hostname, network interface and root paswords / users.

Images prepared by Virtualmaster are minimal and include just basic programs. Your own images may include e.g. complete installation of mail server with spam filter, ready to scale by deploying new instances, or complete web server with your favourite CMS. We set no limits to your imagination when creating an image.

All available images are here: Virtualmaster Images.

Who will manage my virtual servers?

After create of virtual server are you, as your new server administrator, responsible for the condition of his system. All maintenance, updating and parameters change are performed by you.

How do I change RAM size or disk size of my virtual server?

Whenever you want to change your virutal server configuration, you can change parameters in VM server detail screen, just bellow console button.

How long does it take to grow/shrink my virtual server?
Decreasing RAM
Decrease of RAM size is performed instantly. Usually it is not even necessary to reboot your virtual server, but this may differ from distro to distro.
Increasing RAM
If it is technically possible, RAM size is increased instantly. If it is not possible to fullfil your request, RAM size is increased partially. After moving to other cluster node, our staff finalizes ram increase and sends you an email. Usually it is not necessary to reboot your virtual server, but this may differ from distro to distro.
Disk shrinking
In order to be able to shrink disk, you must have some free space on filesystem, at least 15%. Change is applied when you request virtual start next time. So the process is: request change, wait few minutes, shutdown your server and when it is off, start it again, then sit back and wait. Disk shrinking may require substantial time to finish. This time is dependent on disk size, amount of data and metadata and so on.
Disk growing
If it is technically possible, disk size (block device size) is increased instantly. However, it is necessary to resize filesystem as well. One option is to shutdown a server and power it on again. Filesystem will be checked for errors and resized in before start hook. Other option is to run resize2fs /dev/xvda. Sometimes disk size is not resized correctly. In that case, please open a support request.
Change of virtual server level
Change of virtual server level is performed instantly. If the new level is production, you will get e-mail with instructions about backup repository. If you are lowering level from production, backup repository and all backups will be deleted. You may need to shutdown and start your virtual server in order to see additional CPU cores (when new level is production).
Do you block any ports?

No, your virtual server is directly connected to the internet without any port limitations.

I have lost root password of my server. How can I get access?

Possible solutions:

  • Maybe you have allready placed your public ssh key on your server. In that case, you should be able to log in using ssh client from your computer without password.
  • Are there any valuable data? If not, you can simply remove the server and make a new one.

In other cases, you can try following:

  • shutdown your server
  • boot rescue system from VM server panel
  • log in as root with generated password, which is shown at the end of boot sequence
  • now enter theese commands:

# mount /dev/xvda /mnt
# chroot /mnt
# passwd 
# exit
# umount /mnt
# poweroff

After shutting down the server in rescue mode, you can start it in normal operations mode.

Is possible to plan server shutdown and power up?

No. Server shutdown can be done by usual tools, such as at tools or cron and a shutdown command.

Server power on is possible by RESTfull API interface, e.g. by cron and curl tools from another unix server.


Where the servers are located?

Servers are physical located in Prague datacenter Master Internet.

What does availability 99 %, 99,7 %, 99,9 % mean?

Availability is evaluated on monthly basis.

  • Our normal availability is 99,9 %.
  • Our guaranteed availability is 99,7 %.

Some providers are using different methods of calculation. E.g. availability 99,9 % when evaluated over last 365 days may mean that 8 hours of continuous downtime in still within guaranteed bounds.

  • Availability of 99,7 % (monthly) means possible downtime of about 2 hours (129 minutes), or more shorter downtimes, with total lenght not exceeding 129 minutes.
  • Availability of 99,9 % (monthly) would mean possible downtime of about 43 minutes. When there is strong requirement for availability better than 99,7%, customers are encouraged to consider some HA solution on application level. Application load can be spread across multiple virtual servers even in more physical locations and application should survive failure of one server.

One can measure availability of servvices using network monitoring tools like Nagios. In nagios there is option to show "host availability report" or "service availability report".

Who, how and when solves a hardware failure?

This depends on the clients service type and severity of the accident. For testing service, there is no guarantee. Personal level service doesn't include data backup, so we can't guarantee recovering a virtual server from backup if a primary data loss occurs.

We are capable to guarantee server recovery for production service and above. Full recovery of your services might require your cooperation. Time since asking for your cooperation (by email or phone) is not included into the total outage time.

Failure is solved by an authorized Virtualmaster employee who evaluates if the node failure can be fixed or if it's necessary to migrate its virtual servers to a backup node. After the problem is fixed or the servers are migrated, clients (production and above) are asked to check if their virtual servers are fully functional. In case of suspicion of an internal virtual server error, clients will be asked to cooperate while solving the problem.

What is the connectivity to CZ / abroad?

Connectivity is shared, currently it is 100 Mbps. It is assumed that most of the data traffic of virtual servers goes to Czech Republic. Abnormal data traffic (especially that in transit direction) can be charged with 0.15 USD/GB.

Average data amount for one virtual server per month is around 10 GB, out of which around 1 GB is transit data. Amounts considered as abnormal are more than a double of this average for testing and personal user classes, more than five times average for production user class and more than twenty times average for enterprise clients.

I am getting spam or other abusive content from your subnet. How can I report it?

Use email address Attach relevant evidence to the report. Use a working and human operated address. It is prefered to use ARF.

Legal conditions follow the current statutory law. We reserve the right to stop the provided service without prior notice, court order or agreement, in case we hold evidence (or have a reasonable suspicion) about abnormal activity, e.g. sending spam messages, hosting of viruses, malware and spyware, running command&control servers of a botnet, brute force attacks, sharing pornographic material, which contradicts laws of Czech Republic, espionage, phishing and so on.

We also want to inform you, that according to the current statutory law, we are collecting netflow data, which can be provided to Czech police and other statutory organs.

Can I change level of a server?

Yes, it is possible. Server restart or a brief downtime (few minutes) might be required.