General Questions

  • What is cloud hosting?

    Cloud computing is hardware as software… There’s a lot of confusion around this simple, elegant approach to marshaling computer resources. The marketing arms of many technology companies only make things worse with promises of world peace and perpetual motion. Our CTO offers a concise definition: cloud computing is hardware as software.

    Our cloud hosting platform allows you (and your programs, via our API) to request and modify hardware resources as if they were software. Want more memory? Disk? Such physical resources can be adjusted on-demand without having to wait for a technician to power-down the server, open the server, install new RAM, and power back on. With cloud computing, hardware becomes flexible, like software. Read More

  • How do cloud servers differ from virtual private servers (VPS)?

    They are basically the same thing. Both slice up large dedicated servers to share them between customers. Our technology enables every user to run their own isolated copy of an operating system of their choice, providing a greater choice of operating systems, higher performance, deeper configurability, and stronger isolation and security guarantees.

  • How does cloud hosting differ from a CDN (content delivery network)?

    A CDN is used to distribute copies of static media content such as images and videos to the edge of the network, nearer to your customers. This enables them to download these files with lower latency and less chance of bandwidth contention. It only works for static media content, and cannot be used for dynamic content or more general compute applications in the same way as cloud servers.

  • What services does Open Hosting offer?

    We offer a self-managed cloud hosting service. As one of our customers you have full administrator access to your virtual servers and are responsible for the configuration and management of the operating systems and applications that you wish to run.

  • Do you offer managed hosting services?

    No, we only offer a self-managed service. Our infrastructure is very easy to use and you can install and administer it just like physical hardware.

  • Do you provide control panels such as cPanel, Plesk, or PHPMyAdmin?

    We do not have any systems available with preinstalled control panel software, but you can install and run these yourself.

  • Do you offer domain registration and DNS?

    At this time, we ask that you manage your own domains and DNS. Most domain registrars provide DNS service at no additional cost. There are also third party DNS providers, some of them with free offerings such as https://freedns.afraid.org/


  • What support do you offer?

    We support the virtualization infrastructure 24/7. And, we offer email support during Eastern Time business hours (9 am – 6 pm, Monday–Friday) and on a best-efford basis outside that time to help our customers self-manage their services.

  • What SLA do you offer?

    Our SLA is highly competitive. Please see our Terms of Service for more details.

  • How do you schedule planned maintenance?

    Whenever possible, any planned maintenance is scheduled outside of business hours. We will notify you of this by email at least 24 hours in advance.

Billing & Payment

  • What is the price of Open Hosting cloud hosting?

    Please see our pricing page for details.

  • What is the difference between subscription and burst pricing?

    Monthly subscriptions are the most cost-effective option for customers intending to run their servers continuously. You pay a fixed price for that month, regardless of how long your servers are running during that period. We also offer burst pricing for customers who do not run their servers all the time. You deposit a prepay balance with us, from which money is deducted automatically as you make use of the service, rather like a prepay cell phone. The rates are 25% greater than the monthly subscription rates, but when your servers are off you are only charged for disk space. Please see our pricing page for details.

  • Can I purchase a combination of subscription and burst?

    Yes. For example, if you have a server that is only running for 30 hours per month, you can subscribe for the disk space it uses, but only pay by hourly burst for the CPU and memory. For data transfer we recommend taking out a subscription for as much as you expect to use during the month and using burst above that level as required.

  • How do I purchase subscriptions or add prepay balance?

    You can add money to your prepay balance on the ‘Billing’ page under ‘My Account’ on the control panel. Simply enter the amount you would like to add and complete the payment process when prompted. You can purchase a subscription on the ‘Subscriptions’ page. Please enter the amount of CPU, memory, disk and so on that you need in the ‘Quantities’ column, and the number of months’ subscription you would like alongside this in the ‘Extra months’ column. You will then be prompted to complete the payment process.

  • Why has my card payment been refused?

    Online transactions for services delivered over the Internet are particularly vulnerable to fraud, so our payment processors perform stringent security checks on them. If payment by credit card fails, you may use Google Checkout or Paypal.

  • What should I do if my card details change?

    To update your details, you will need to use the “Pay with Credit Card” option (rather than “Pay with Stored Details”) the next time you wish to make a payment, then go through and pay with the new card. Future payments will then be taken from the new card.

  • Can I pay automatically every month?

    Yes! The advantages of this are (i) no annoying reminder emails, and (ii) the security of knowing that you’ll never accidentally run out of credit.

    To set up recurring billing, go to My account > Billing, and top up your prepay balance as usual, using a credit card. After you have paid and verified your card, you will see an options screen. Under ‘Balance’, choose the billing options you want. For example: Automatically top up my balance by $50 every time it drops below $5, charging my stored details (up to a maximum of $250 per month).


  • What are drives and servers and how do I use them?

    Drives are just like physical hard disks or CDs. They store your operating system, applications and data, and are persistent across server reboots. Servers are virtual machine instances, and may have one or more drives attached to them. They are either running or powered off. When a server is running, the cloud provides VNC access. When a server is powered off, you can configure the CPU, memory, drives and IP addresses which it uses. Some of our competitors have less-flexible products in which every server has exactly one drive. Our approach is more general, allowing you to attach several drives to a single server, or building several alternative configurations, which boot from the same drive. (However, only one running server can access a given drive at any one time.)

  • How are the sizes of drives and servers measured?

    Like a physical hard drive, drives are measured in gigabytes (GB). Servers have two adjustable sizes: the amount of memory (in MB) and the amount of CPU bandwidth (in core-MHz).

  • How large a server and drive do I need?

    This will depend entirely on what you plan to use your server for: everybody’s requirements vary. However, a good starting point is to configure with the same sizes as you would use if you were purchasing a physical server for your application.

  • How do I create a server?

    On the right hand side of the control panel in your account, you can follow the Add Server wizard to create a server. We offer various options:

    • Use a pre-installed system.
    • Self-install from a CD. There are many install CDs to choose from, for different OSes.
    • Upload your own CD and boot your server from that.
  • How do I access and control my server?

    The cloud provides basic VNC access to servers, which works from the BIOS onwards, and allows you to install, configure and recover your operating system, even if nothing is running inside your server. In normal use, you should access your server by a native method (e.g. SSH, VNC installed inside your operating system on port 5901, Windows Remote Desktop/RDP), which will provide superior performance.

  • What VNC software do you recommend?

    Our VNC service requires a reasonably recent client. TightVNC works well on Windows, and clients based on gtk-vnc such as Vinagre work well on Linux. The RealVNC Enterprise Edition Viewer is good on Linux, Windows and MacOS if you set the “Always use best available color quality” (or set FullColor to Yes in the Expert panel on the MacOS version of RealVNC). The Linux and MacOS versions of this are available as a free download on the RealVNC web site.

    Neither the Apple Remote Desktop VNC client, Chicken of the VNC, nor JollysFastVNC work correctly on MacOS as they don’t support some of the newer protocol features which we use.

  • Why does my password work in VNC but not in RDP/SSH?

    Please check your local keyboard settings. VNC will always enter keystrokes as if from a US keyboard, which may cause problems with some special characters. By contrast, RDP and SSH will always maintain the settings from your local keyboard.

  • What is the minimum size of a single server or drive?

    The smallest single server you can create is 500 core-MHz CPU, 256 MB RAM, with a 1 GB disk drive.

  • How many servers and drives can I have?

    There is no limit to the number of servers and drives that you can have in your account.

  • How are my servers and drives distributed between physical hosts?

    When you create a drive, it is allocated on a randomly chosen host with sufficient free space. When you start a server, our system prefers to place it on the same physical host as its drive(s). If this is possible, the server can directly access the underlying physical disk. Otherwise, if the host containing the drive is already too busy, the server will be started on a nearby host and it will access its storage by peer-to-peer iSCSI over gigabit Ethernet.

  • One of my drives is a backup of another. Can I specify that the two drives should be allocated on different physical hosts for better resilience?

    Yes, although this is a new feature and only possible through the API at present. When you create the second drive, pass in 'avoid DRIVE1' where DRIVE1 is the UUID of the first drive.


  • What do you mean by core-MHz?

    The effective speed of modern CPUs is determined both by the clock speed of the processor (in MHz) and the number of independent execution units (cores). For a given processor design, the available CPU bandwidth is roughly proportional to the product of these two.

  • How do I set the number of CPU cores?

    This is under the advanced settings on the server configuration page. (Click Edit when your server is powered off to find this page.)

  • What is the maximum CPU for a single server?

    The maximum CPU value for a single server is 20000 core-MHz.

  • What is the minimum CPU for a single server?

    The minimum CPU value for a single server is 500 core-MHz.

  • What do the Shutdown, Hard Power Off and Hard Reset buttons do?

    The shutdown button sends an ACPI power button signal to the server operating system, exactly as the ‘soft power-off’ button does when pressed on a physical machine. Normally operating systems are configured to shutdown or hibernate when this is done.

    We recommend that you watch over VNC if the system does not appear to shut down immediately: additional setup may be required in some cases. For example, Linux users may find they have to install ‘acpid’.

    The hard power off button behaves exactly as if you have switched off a physical machine by turning off the power. You should only use this if your server has crashed; otherwise you should shutdown using the button or from inside your operating system.

    The hard reset button sends a non-maskable interrupt to the server CPU in exactly the same way the reset button does on a physical machine. You should only use this if your server has crashed; otherwise you should reboot from inside your operating system.


  • What happens to my data when my server shuts down?

    Data stored on your virtual drives is persistent and will be available when you restart your server, just as it would be on a physical hard disk. This means that you can install software and save data exactly as you would on a physical server, unlike some other cloud solutions.

  • What is the maximum size of a single drive?

    The maximum size for a single drive is 2 TB.

  • What is the minimum size of a single drive?

    The minimum size for a single drive is 1 GB.

  • How do I attach more than one drive to a server?

    You can set this in the server configuration page. (Click Edit when your server is powered off to find this page.)

  • Can I attach one drive to more than one server?

    No. However, you can run file-sharing protocols such as NFS or Windows File Sharing from one server to another over a private network VLAN.

  • I have uploaded an ISO 9660 image (.iso file). How do I boot a server from it?

    On the server configuration page, set the drive media type for the drive containing the image to cdrom and ensure the boot radio button is activated next to it. If you are installing a server from the CD, remember you will also need another drive attached onto which to install your operating system.

  • What is the difference between IDE, SCSI and Virtio drives? Which do you recommend?

    In practice you should stick with the IDE emulation, which offers good performance and compatibility. The SCSI and Virtio drive types are intended for specialized applications. (Note that our virtio drives have writeback caching enabled, so you will need Linux 2.6.32 or later, which supports barriers over virtio, to be able to use these safely. No released version of the Windows virtio drivers support barriers, so the virtio block transport cannot yet be used safely under Windows.)

  • What storage performance can I expect?

    You should be able to achieve around 30-40 MB/s streaming read and write performance from your virtual drives. However, contention with other users accessing the same underlying RAID arrays can result in lower performance, especially at peak times. This affects writes more than reads as we cannot safely cache disk writes as aggressively.


  • How do I get a static IP address?

    Servers are configured with a dynamic IP by default, but you can purchase a subscription for as many static IP addresses as you need through the subscriptions page in your account. You then need to allocate the actual addresses by clicking ‘add static IP’ on the control panel, and configure the static IP in your server configuration.

  • How do I use multiple static IPs on the same server?

    You will need to configure this inside your server. The networking option on the server configuration page just sets the IP address that the server is supplied by DHCP and uses for VNC. This should be the ‘primary’ IP of the server, but you can also use any other static IPs in your account if you configure these inside your server operating system.

  • How do I remove a static IP address from my account?

    Since all the static IP addresses in your account are available to be used by all servers at any time, then you will need to stop your servers before you will be able to delete a static IP address from your account.

  • How do I set reverse DNS for my static IP addresses?

    Please email the IP address, host name, and account email details and we will set this up for you.

  • Is Internet bandwidth limited?

    We do not cap or throttle the connection. Our upstream provider is Internap.

  • How can I track my bandwidth use?

    A report of received, transmitted and total bandwidth for your account is shown on your billing page, with links to display traffic graphs. You can edit the URL parameters on these graphs to adjust the timeframe and offset. ?Per-server traffic graphs are available from the control panel. There is a link next to the VNC IP address when the server is running.

  • What happens if I go over my subscribed bandwidth limit?

    If you go over your subscribed bandwidth limit, then you will be charged the hourly burst rate for additional bandwidth and this will be deducted automatically from your prepay balance. When your prepay balance runs out there is a buffer of 10-20 GB which you can use. After that your servers will be automatically shut down. ?As your prepay balance is being used up, you will receive warning emails, letting you know you should top up (or increase your subscriptions).

  • Do you charge for network bandwidth?

    Yes. We charge for both inbound and outbound traffic. We do not cap or throttle the bandwidth to / from your servers.

  • Will I be charged for bandwidth between my servers?

    Yes, we charge for all bandwidth usage that does not go over a private VLAN.

  • What is a private VLAN and why would I use it?

    A VLAN acts like a private gigabit Ethernet switch connecting your servers together via a second virtual Ethernet card in each server. This network is isolated from the Internet and other customers. Bandwidth over a VLAN is not charged nor metered.

  • How can I configure a private VLAN?

    First, purchase a private VLAN subscription. Then add it to your account in the control panel. Then, edit each server’s configuration to use your private VLAN. This is under the Advanced settings.

  • What is the difference between the virtual network cards you offer? Which do you recommend?

    We recommend the Intel PRO/1000 as it is the fastest, and is widely supported in modern operating systems. If you are running a relatively old OS, such as Windows XP, the Realtek RTL8139 is an older model which should be supported by your OS.

  • My server won't connect to the internet - what can I do?

    If you can’t connect to the internet, you can still connect to the VM using the provided VNC server. This allows you to ensure that everything is running normally, and fix any configuration issues which may be affecting the network connection. RHEL or CentOS users may find that they are affected by this known but within their OS.

  • Do you block any network traffic?

    We block outbound connections to smtp, ftp, ssh and telnet servers to prevent abuse of our trials for sending spam or conducting dictionary attacks against other Internet hosts. Port 5900 is used for running the VNC console.

  • How can I send email from my servers? Can you lift the SMTP block?

    We are happy to lift the smtp block so you can send email from your servers. Please email a request a confirming that:

    • any mailing lists you run on the servers are strictly opt-in, and
    • all messages sent to those mailing lists contain instructions on how to unsubscribe.
  • How can I connect to my server over a VPN?

    You would need to run VPN software inside your server, just as if it were a physical server.


  • How do I resize my server?

    When your server is powered off, go into the server configuration page, and then simply adjust the CPU and memory settings.

  • Can I change the size of my server while it is running?

    No. Operating systems are not able to recognize changes of this sort and would crash if we enabled them.

  • How do I grow my disk?

    To increase the size of your drive, shut down the server it is attached to, choose Edit for that drive in your control panel and increase the size in the dialog. After resizing the disk, you can restart your server attached to it but will then need to grow any partitions and filesystems on it to make use of the extra space. (Our preinstalled Linux images do not have partitions but just a single filesystem filling the entire drive, so it is sufficient to run resize2fs directly on the hard disk block device node to grow this filesystem.)

  • How do I shrink my disk safely?
  • How do I scale automatically with load?

    You can use our API to start and stop servers when your application detects that it needs extra computing power. Building an application that scales across multiple machines like this is done in the same way as it would be on physical hardware which you could programmatically turn on and off, but is beyond the scope of this FAQ.

Uploading CDs/Server Images

  • How can I upload my own ISO CD images?

    You are welcome to provide your own ISO CD images to use on your servers. You can upload these in one of two ways:

    • using our API with the Open Hosting-upload script;
    • if the drive is less than 1GB, using the drive upload web form found under ‘Edit drive’.
  • How can I upload my own server images?

    You can use any of the methods mentioned in the previous question to upload a server image to your account. Using our API upload tool is likely to be the best choice if the image is large, as this uploads in chunks and has the option of resuming an interrupted upload.

  • What format server images do you support?

    We accept only raw drive images that are the same as a physical drive, with block device, partition tables etc.

  • How can I migrate Linux KVM or QEMU virtual machines into your cloud?

    If your drive is already in the raw format supported by these hypervisors, it is ready to upload using our API upload tool unchanged, as described above. If your drive is in qcow2 format, you will need to convert it to raw format before uploading. You can do this with the command qemu-img -f qcow2 -O raw drive.qcow2 drive.raw where drive.qcow2 is the qcow2 file you want to convert to the raw file drive.raw.

  • How can I migrate VMware virtual servers into your cloud?

    You will need to convert the drives in VMware vmdk format into raw files before you can upload them with our API upload tool. To do this, you will need the qemu-img command distributed as part of qemu and qemu-kvm. Run it as qemu-img -f vmdk -O raw drive.vmdk drive.raw to convert the vmdk drive drive.vmdk into a raw file drive.raw.

  • How can I migrate physical servers into your cloud?

    If you have physical servers that you would like to migrate into our cloud, you should boot your server from a live CD and then run the Open Hosting-upload script to upload the hard disk block device. However, please note that uploading a large drive this way can take a very long time depending on your Internet connectivity. It may be quicker to install afresh in our cloud and copy your data across.


  • What can I do with your API?

    Our API allows you to do everything you can do on our web control panel: the web control panel is actually implemented on top of the API.

  • How do I use your API?

    Please refer to the dedicated documentation for our API and see our blog.

  • When attempting to use the API, I see a ‘Bad operation’ error message – why?

    If you see this error message while attempting to access the API, you are sending arguments which the API server does not accept. One possibility is that you are using a VNC password longer than eight characters. The API only accepts passwords with eight characters or fewer.

Backups/ Redundancy

  • What redundancy does your infrastructure provide?

    Our virtual drives are allocated on RAID1 disk arrays. These provide a similar level of reliability to RAID1 on a traditional dedicated server, and ensure that any failure on one virtualization host will not affect others. By contrast, many of our competitors use centralized disk servers (SAN/NAS) that act as a single point of failure.

  • What is your uptime guarantee?

    Our SLA offers compensation whenever we fail to meet our 100% uptime guarantee. Please see our Terms of Service for more details.

  • What solutions do you recommend for backups?

    We do not provide an integrated backup service, but you can backup your data yourself, either by running a backup server on our infrastructure or using a third-party backup service such as rsync.net.

  • Can I make a backup copy of a drive?

    We provide a drive copy function which duplicates a drive. You have to power down a server while this takes place, and it may take some time if the drive is large.

Firewalls/ Security

  • How do I set up a firewall on my servers?

    From the Control Panel click Edit on a stopped server. On the Edit page, in the Firewall section, check Enabled. By default, all ports are blocked, so specify the ports you want to open.

  • How can I disable VNC on a server?

    On the server configuration page, you can disable VNC access by leaving the VNC password field blank.

  • How can I encrypt VNC connections to a server?

    We do support TLS VNC using the VeNCrypt extensions, which some VNC clients support. You can enable this option through the advanced settings in the server configuration page. Note there are several different incompatible schemes for TLS on VNC. gtk-vnc/vinagre on Linux is a popular client that works with VeNCrypt.

  • What access do Open Hosting staff have to my servers?

    Open Hosting staff do not have access to your server passwords. The only access they have is the ability to see the VNC display, which they may use from time to time to check that your server is running.

Load Balancing & Clustering

  • How do I set up load balancing between my servers? Which tools do you recommend?

    We recommend that you set up a small server in your cluster, running a load balancer, such as HAProxy or Pound, and connect it to your backend web servers over a VLAN.

OS Specific Advice

  • What should I do if my Windows Server hangs on a restart?

    Shut down your server and click the Edit button to go to the configuration page. Then click Expand on the Advanced section. Set the number of CPU cores simulated to 2 (or 4 or 8 if your total core-MHz is greater than 5000).

  • How do I extend drives on Windows Server 2003?

    Here is the procedure to extend drives on Window Server 2003.

    Install Windows:

    • Install server (this will create single System partition, which you cannot extend)
    • Switch off server and increase disk size on EH control panel
    • Start server again

    Create new partition:

    • Open up the disk management window (Administrative Tools -> Computer Management -> Storage)
    • Right click on the unallocated space and create a new partition
    • Follow the wizard to create basic primary partition formatted with NTFS – this will create a second partition that you will be able to extend

    Extend new partition:

    • Switch off server and increase disk size again
    • Start server again
    • Open up disk management as in stage 4 to see unallocated space
    • Open command prompt
    • diskpart.exe
    • List volume
    • Select volume
    • Extend – this will extend the selected volume to fill the available unallocated space
    • check disk management window to see extended partition

    See the Microsoft site for further instructions. We also recommend setting the virtual NIC in the advanced server configuration settings to Realtek RTL8139, rather than the default Intel PRO/1000.

  • I am running a Windows Server in my account, and the system time is consistently off by a number of hours.

    The issue here is the emulation of the hardware clock by the virtualization system. On Linux and other Unixes, the convention is that the hardware clock is permanently set to UTC (i.e. GMT without DST), and the operating system adjusts this for display. On DOS and Windows, the convention is that the hardware clock stores local time, and that the operating system adjusts this when DST starts and ends. We cannot support both of these behaviours, since our virtualization layer does not know what operating system it will boot when it sets up the virtual hardware to start a server. We have chosen the UTC behaviour. One recommended solution involves a registry setting of RealTimeIsUniversal=1, which you can apply to make Windows adopt the Unix behaviour. We recommend you try this approach.