As I’ve mentioned in previous posts, there are different techniques to build a cloud, every technique have it’s own characteristics and downsides. As a customer it’s important to know what your cloud computer will be used for, to be able to make a good decision.
The cheap cloud
The simple and cheap cloud, the computers is often "containers" inside the host. They share kernel with the host, and it’s capabilities are limited to the modules loaded into the host kernel. Many service providers oversell their platforms, so if every container is fully utilized, the performance will be lousy and if unlucky; everything will go down.
Many providers build their platforms on OpenVZ or Virtuozzo, important to notice: Not every provider using OpenVZ or Virtuozzo oversells, but some do. Since it’s fairly easy to do in those platforms. One more reason for using OpenVZ is that the hosts don’t need to share storage, making the hardware platform cheaper, but if the host that the container is running on goes offline, the VPS-service is interrupted until the hosts is back online.
The HyperV cloud
HyperV is Microsoft´s Virtualization technology, it runs solely on Windows Hosts but has kernel modules for better performance when running Linux. HyperV is not suitable for elastic clouds, because of the license agreements, therefore a cloud built on HyperV is built for persistent machines and systems that don’t need to scale on a short notice.
An elastic cloud such as The City Cloud Service is designed for quick scaling, flexibility and great uptime. Each Virtual Machine has it own hard drive and get access directly to the hardware through the hypervisor (the heart of the virtualization environment).
The shared storage makes it possible to migrate the virtual machine to an online host if the current one goes down. The biggest benefits of a elastic cloud is the virtually endless possibilities of on-demand scaling, as much power as needed, when needed. This is the feature i built my system "Stina" on, and there will be more on the topic later.
The City Cloud is also built on standardized components, making migration of machines to and from the cloud possible, at least on a technical level.
The Amazon Aloud
The Amazon Aloud, EC2 has set a standard of it’s own on how a cloud should be, their own Virtual machine format AMI is both brilliant and worthless at the same time. Brilliant in how it makes it possible for developers to utilize Amazons payment functions, so they can make some money on their applications. On the same time, it’s not a very widely accepted standard and moving existing machines to EC2 is not the simplest task.
All in all, the Amazon cloud is great, but it takes some knowhow to use it, and to really appreciate all the functions and ways you can integrate different Amazon Web Services.
This short walk-trough of different cloud types is very brief and should not be considered as a complete guide to the cloud, but you can use it as a support in your search for a service provider. Naturally you can always contact me if you need any help or guidance.