Cloud Hosting FAQ

Our cloud computing FAQ covers everything from "What is cloud hosting?" to "How do I set up load balancing between my servers?". If you cannot find the answer to your question here, please email support@elastichosts.com and we will respond as soon as possible.

FAQ Sections

General Questions

Getting Started Questions

Support Questions

Billing and Payment Questions

Technology Questions

Overview Questions

CPU Questions

Memory Questions

Storage Questions

Networking Questions

Uploading CDs / Server Images Questions

Converting Server Images Questions

Scaling Questions

API Questions

Backups / Redundancy Questions

Firewall / Security Questions

Load balancing / Clustering Questions

OS Specific Advice

Dedicated / Hybrid Solutions Questions

General Questions and Answers

What is cloud hosting?
The term 'cloud' is used to describe a number of very different products, but in our case, it refers to on-demand, scalable, virtualized servers accessible over the internet.
How do cloud servers differ from dedicated servers?
When buying a dedicated server, typically you have to pay an initial set-up fee and commit to a contract for a year or more at a higher minimum price point than a cloud server. There is usually a lead time on the hardware, and it is difficult to change the server specification as your needs evolve, forcing you to buy something large enough for your application to grow into. You pay for the server 24 hours a day, not just when you want it up and running.
Our cloud servers, on the other hand, can be deployed immediately from our easy-to-use web control panel and have no setup charge, a low minimum price point, and no commitment to a contract. As your requirements change, you can instantly scale up and down the resources you use, and can even pay-as-you-go for just the hours your servers are running.
How do cloud servers differ from traditional virtual private servers (VPS)?
Traditional VPS providers slice up large dedicated servers to share them between customers. Typically VPS providers use a container technology such as Virtuozzo to isolate multiple users on a single server from one another whilst running a single shared instance of the operating system. By contrast, our KVM 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 shared hosting?
Shared hosting solutions usually only give you access to your server through a web control panel, where you can manage a number of websites hosted on that server. With our cloud server, you get full adminstrator control over your server and the ability to install any software you like and configure it exactly how you wish.
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 ElasticHosts 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 system 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. However, we can recommend partners if you would prefer a fully-managed product.
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?
No, this is something you need to source from a third-party supplier. Many domain registrars will bundle a free DNS service when you purchase a domain. There are also third party DNS providers, some of them with free offerings such as http://freedns.afraid.org/.
Can you provide consultancy on optimising my system for performance and scalability on your platform?
Most of our customers will be able to install and configure their systems themselves, but if you have particularly specialised requirements, we can offer consultancy and systems support for £150/$225 per hour. We can also recommend partners who can help with more general server software installation and configuration.
Do you have reseller or referral schemes?
Yes, please see our resellers page for details.

Getting Started Questions and Answers

What does the trial include?
The trial gives you full access to our system and includes 2000 core-MHz CPU, 1024 MB RAM, 20GB disk space and 5GB data transfer, which is enough capacity to run a medium-sized server or several small servers.
Are there any restrictions on trials?
- The trial is limited to 2000 core-MHz CPU, 1024 MB RAM, 20GB disk space and 5GB data transfer. It lasts for 5 days.
- During the trial, we block outbound connections to smtp, ftp, ssh and telnet servers - ports FTP (tcp 21), SSH (tcp 22), telnet (tcp 23), SMTP (tcp 25), POP3 (tcp 110), IMAP (tcp 143), SIP (udp 5060), VNC (tcp 5900-2) and Runescape (tcp 43594-5) - to prevent abuse of our trials for sending spam or conducting dictionary attacks against other internet hosts.
- We ask triallists not to run Minecraft or other game servers. Game servers may be powered off without warning.
How do I run Windows during my trial?
There are 3 options for setting up a server to run Windows during your trial:
- Purchase a licence for that month on the subscriptions page of your account and then use one of our preinstalled images. We can't offer preinstalled images of Windows for free as part of the trial, as we have to pay Microsoft license fees for these.
- Select 'self-install from CD', rather than 'preinstalled images', and then install from the Windows Server 2008 Trial CD yourself.
- Upload your own install CD using our cloud hosting upload tool or FTP to ftp.<zone>.elastichosts.com (e.g. ftp.lon-p.elastichosts.com) with your account UUID and Secret API key as shown on your account profile page.
Is it possible to have a trial for longer or with extra infrastructure capacity?
We are happy to consider requests for larger and/or longer trials on a case-by-case basis. Please email us if you would like extra time or resources.
When I sign up, can I continue to use the servers I created during the trial?
Yes. You can purchase subscriptions or add prepay balance at any time from inside your account. If you sign up before the end of your trial, you will be able to continue running your servers uninterrupted.

Support Questions and Answers

What support do you offer?
We offer telephone and email support during UK business hours (9am - 6pm, Monday-Friday). We support the virtualization infrastructure, but our customers self-manage their operating system configuration and applications.
What SLA do you offer?
Our SLA is highly competitive, offering 100x credits for any unscheduled downtime longer than 15 minutes, up to 1 month's credit. See our Terms of Service for more details.
How do you schedule planned maintenance?
Whenever possible, any planned maintenance is scheduled outside of UK business hours. We will notify you of this by email at least 24 hours in advance. We will never schedule maintenance simultaneously in more than one of our sites, ensuring that they offer full redundancy to each other.

Billing and Payment Questions and Answers

What is the price of ElasticHosts cloud hosting?
Please see our pricing page for details.
What is the difference between subscription and burst use?
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 an 'hourly burst' pricing model 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 twice the subscription rates, but when your servers are off you are only charged for disk space.
Please see our pricing page for more details.
Can I purchase a combination of subscription and burst use?
Yes. For example, if you have a server which 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 bursting 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.
What currencies do you accept?
We accept UK pounds sterling (£, GBP) for accounts in our lon-b or lon-p availability zones in our UK data centres, and US dollars ($, USD) for accounts in our sat-p zone in Texas, USA. Your credit card will automatically convert from your local currency into GBP or USD as required.
What payment methods do you accept?
We accept card payments with Visa or Mastercard in both the UK and the US. In the UK, we also accept Google Checkout payments. For sums of £300 or more, we accept bank transfers to our UK bank account.
Do you accept PayPal?
No, not at present.
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. The most common problem is a failure in 3D-Secure checking. If you experience this, you should contact your card issuer to ask them to enable Verified By Visa or MasterCard SecureCode on your account. If your bank does not support this, you will need to use Google Checkout.
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.
Why hasn't my Google Checkout payment been credited?
There is a short delay before your Google Checkout payment is credited to us while Google perform security checks on the transaction. This is typically 15 minutes but can be up to a few hours if this is the first time you have paid us and the transaction is relatively large. You will get an email from Google indicating that your order has been shipped as soon as Google approve it and it is credited to your account.
Can you bill me without UK VAT (sales tax)?
Yes we can, if you are based outside the UK. If you are based in the EU, please send us your EU VAT registration number. If you are based outside the EU, please send us proof of local company registration - such as a company number and copy of your registration certificate, and a link to your local Companies House. VAT will then be automatically removed from your bills.
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).
Sorry, recurring billing is not currently available for customers using Google Checkout. Please note that you will be billed 7 days in advance of your subscription being renewed.

Technology

Overview Questions and Answers

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.
Make sure you create a sufficiently large drive to store your operating system, applications and data.
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 colour quality" (or set FullColour 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.
What is the maximum size of a single server or drive?
The largest single server you can create is 20000 core-MHz CPU, 8192 MB RAM, with one or more 2TB disk drives.
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. This is typically sufficient for a Linux applicance such as a DNS server.
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.
What physical infrastructure is ElasticHosts based on?
The virtualisation hosts in lon-p and sat-p have dual quad-core Xeon E5420s at 2.5GHz with 32GB of RAM and 4-6x 0.75-2TB drives each. The virtualisation hosts in lon-b have dual quad-core Opteron 2352/2378s at 2.1/2.5GHz with 32GB of RAM and 2-3x 1-2TB drives each. They run our in-house cloud hosting platform, which is built on open source technologies including Linux, qemu-kvm, LVM and iSCSI. The disks are arranged into RAID 1 pairs, and virtual disks are allocated out of this pool of RAID 1 arrays.
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.
One of my servers is a backup of another. Can I specify that the two servers should be allocated on different physical hosts for better resilience?
Yes, although again this is a new feature and only possible through the API at present. When you create the second server, pass in 'avoid:server' plus a space-separated list of the UUIDs of the servers you wish to avoid. As above, you can avoid particular drives too: pass in 'avoid:drive' with a space-separated list of the drive UUIDs to avoid.

CPU Questions and Answers

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.
Concretely, if you create a virtual server with 2100 core-MHz of CPU allocated, you should expect performance roughly equivalent to a single core of AMD Opteron 2352 clocked at 2.1GHz, and this performance varies linearly in proportion to the core-MHz number.
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.
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.
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.

Memory Questions and Answers

What is the maximum memory for a single server?
The maximum memory value for a single server is 8GB RAM, or 16GB within our lon-b zone.
What is the minimum memory for a single server?
The minimum memory value for a single server is 256 MB RAM.

Storage Questions and Answers

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 filesharing protocols such as NFS or Windows File Sharing from one server to another over a private network VLAN.
I have uploaded an ISO9660 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 specialised 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 30-40MB/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.

Networking Questions and Answers

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 us with the IP address, host name and account email details and we will set this up for you.
What internet bandwidth can I expect? Is this limited?
In each of our availability zones, your virtual machines are connected directly to a major ISP's backbone network at 1Gbps speed. We do not cap or throttle the connection. Our upstream providers are Peer 1 in lon-p and sat-p, and C4L in lon-b.
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. See our pricing page for details.
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 chargeable.
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.
Do private VLANs work between your availability zones?
No. A private VLAN can only be set up within a single availability zone, so any traffic sent between our different availability zones will be charged at the standard rates.
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/2003 (or very occasionally Windows 2008), the Realtek RTL8139 is an older model which should be supported by your 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 us to request this, 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.

I use VMWare. Is it possible to upload VMware disk images and use them on the ElasticHosts system?
Only indirectly. Our system requires either DVD or CD images in .iso format, or raw disk images - the equivalent of taking the stream of bytes off a physical disk and saving them in a file. A .vmdk file is a long way from raw format. However, qemu does have tools to convert these. On a Linux system, you can use: $ qemu-img convert inputfilename.vmdk -O raw outputfilename.raw to convert a .vmdk into a raw disk image that our system can use. Be aware that a raw image is probably larger than the .vmdk, which is a compressed format.
With a converted VMware image, is there anything else I need to know?
Yes - you might still have issues getting it to work. Our recommendation is always to create a new system inside the ElasticHosts servers and install what you need, and send over data. Windows guests in particular dislike having their virtual hardware swapped around, so there are few guarantees that you'll have a reliable system after conversion. That said, we recommend:
1. Remove VMWare tools before you shut down for conversion. This is the most important step.
2. Make sure when you run the converted file, you set the number of cores to at least two. This is in the advanced options for the server, and does seem to make Windows guests in particular more reliable.
3. Some users have had more success with the older RealTek virtual network card than the Intel one. If you do have issues, it's certainly worth swapping.
I don't have a Unix/Linux system. Can you convert the image for me?
A: Yes, we can. FTP the .vmdk file to the ElasticHosts ftp site (as described here) and we'll see what we can do. You may wish to zip it first to make it faster to transmit. Note that we reserve the right to change our policy and charge for conversion services in future.

Uploading CDs / Server Images Questions and Answers

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 three ways:
- using our API with the elastichosts-upload script;
- by FTP to ftp.<zone>.elastichosts.com (e.g. ftp.lon-p.elastichosts.com) with your account UUID and Secret API key as shown on your account profile page; or
- 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.
We can also accept USB hard drives with drive images on, to copy across directly. Please contact us if you would like further details of this.
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. However, we do accept converted VMWare images - see the VMWare section below for details.
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 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 elastichosts-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.
Can I send you data on a physical disk to copy into my account?
Yes, see above.

Scaling Questions and Answers

How do I resize my server?
When your server is powered off, go into the server configuration page, then simply adjust the CPU and memory settings.
Can I change the size of my server whilst it is running?
No. Operating systems are not able to recognise 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?
It is very important to shrink the size of your filesystem and any partitions using your operating system BEFORE trying to shrink the drive itself! If you don't do this, you will chop the end off the filesystem when you shrink the drive leading to serious corruption. If in doubt, we strongly advise against attempting a drive shrink because of this risk. However, once you are sure it is safe to do so, you can shrink the virtual drive by shutting down the attached server and decreasing the drive size via the control panel.
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 which 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.
How do you recommend configuring server clusters appropriate for each stage in my website's growth?
Whilst the exact answer will vary according to your web application's architecture, we recommend the following cluster architectures to back a typical site as it grows, progressing in order:
1. Single small server with standard disk, running entire LAMP stack
2. Single large server with dedicated disk, running entire LAMP stack
3. Multiple large servers in classic 3-tier web application architecture, interconnected over private network VLAN:
  - Clustered database servers with dedicated disk
  - Front-end application servers with standard disk
  - Load balancer(s) running Pound, HAproxy, etc
Note that in the second stage a single larger server with dedicated disk will typically give better performance than splitting immediately into multiple small servers, since disk I/O is improved and there are no extra latencies from cross-network communication.

API Questions and Answers

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 cloud hosting API.
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 Questions and Answers

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 ensures that any failure on one virtualization host will not affect others. By contrast, many of our competitors use centralised disk servers (SAN/NAS) which 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.
If you run your backup server in the same availability zone as the main server, you can transfer data between the two for free over a VLAN, but both would be affected by a catastrophic failure of the entire availability zone. On the other hand, you can survive such failures if you provision your backup server in another availability zone, but bandwidth between the two sites will be billable.
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. We aim to introduce instant snapshots in the medium term, which will be possible while a server is running.

Firewalls / Security Questions and Answers

How do I set up a firewall on my servers?
You can purchase a firewall for your server (for charges, see the pricing page). To add a firewall to your server, from the ElasticHosts control panel, first shut down the server, then click Edit. On the Edit page, click "Enabled" next to Firewall. By default, all ports are blocked: list the individual ports you wish 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 ElasticHosts staff have to my servers?
ElasticHosts 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 Questions and Answers

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.
How can I configure my system to fail over between your two clusters?
The easiest way of configuring failover is to use a DNS-based failover method. Set a low TTL on the A record for your website to avoid excessively long caching, and alter this to point to the backup server when the production server is down. There are third-party DNS providers who offer this kind of service as part of their DNS hosting offering.

OS Specific Advice

I am using a preinstalled Windows server with a licence purchased from ElasticHosts - how do I activate my server?
Go through the normal activation process and leave the product key blank. The product key is already built into the system and will be picked up automatically.
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 using Windows and having networking problems - what should I do?
We have known some customers have problems with Intel network cards and Windows. As a first line of attack against networking problems, we recommend trying the Realtek RTL8139 network card, an older model.
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.
On my Windows Server, I have set a system time check at five-minute intervals as recommended in the build notes, but my system time is not correcting itself. Why not?
Your Windows system time may not be running. Ensure you have set the Windows time service to start automatically, or you will not be reaching an NTP server.
I am running Windows Server 2003, and the server is very slow, with slow disk i/o and extremely high CPU use. What can I do?
This may be because your server has started using PIO transfer for disk, not DMA, which we have seen happen to Windows 2003 servers. To change this back you will need to uninstall the IDE driver and reboot the server. In Device Manager, uninstall the IDE channel from the IDE controller, then restart.

Dedicated / Hybrid Solutions Questions and Answers

What is dedicated disk storage, and what are the advantages?
Our normal virtual drives are allocated from RAID1 disk pairs shared between customers. This means that when one customer is heavily accessing their disks, your accesses may be slower if they happen to be on the same disk pair.
If you need uncontended access to your virtual drives, we can allocate a RAID1 disk pair specifically for your use, with no other customer drives on it. This means that performance on your drives cannot be degraded by the activity of other ElasticHosts users.
When would you recommend using dedicated disk storage?
We recommend considering a dedicated disk pair if you have heavy IO requirements, or have a particularly IO-latency sensitive application.
Do you offer dedicated servers and hybrid cloud/dedicated clusters?
In conjunction with our partners Peer 1, we can offer hybrid solutions in the lon-p and sat-p availability zones, with Peer 1/ServerBeach dedicated servers and our cloud servers connected together on a high-speed local network.
When would you recommend a hybrid solution?
Hybrid solutions are particularly useful where you need a high-spec database server with high IO performance requirements which is better run on dedicated hardware, but want the flexibility of our cloud platform for your front-end web servers and load-balancing. A combination including dedicated machines is also worth considering if you need particularly low latency for compute-heavy jobs or are specifying servers with more than 8GB of RAM.

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FAQ Sections

General Questions

Getting Started Questions

Support Questions

Billing and Payment Questions

Technology Questions

Overview Questions

CPU Questions

Memory Questions

Storage Questions

Networking Questions

Uploading CDs / Server Images Questions

Converting Server Images Questions

Scaling Questions

API Questions

Backups / Redundancy Questions

Firewall / Security Questions

Load balancing / Clustering Questions

OS Specific Advice

Dedicated / Hybrid Solutions Questions

General Questions and Answers

Getting Started Questions and Answers

Support Questions and Answers

Billing and Payment Questions and Answers

Technology

Overview Questions and Answers

CPU Questions and Answers

Memory Questions and Answers

Storage Questions and Answers

Networking Questions and Answers

Uploading CDs / Server Images Questions and Answers

Scaling Questions and Answers

API Questions and Answers

Backups / Redundancy Questions and Answers

Firewalls / Security Questions and Answers

Load Balancing / Clustering Questions and Answers

OS Specific Advice

Dedicated / Hybrid Solutions Questions and Answers

sales@elastichosts.com

+1 415 358 5210

+44 (0) 20 7183 8250