Tips for Purchasing Cloud Computing Services

Shirin Elkoshairi of ColoAdvisor is a Principal Consultant, who works with clients in making informed decisions related to cloud, colocation and managed hosting.

Shirin Elkoshairi SHIRIN ELKOSHAIRI ColoAdvisor

There are a many factors to consider when selecting a cloud computing provider. The good news is that many cloud providers don’t have long term agreements to lock you in one place for a considerable time. In any case, it makes sense to carefully evaluate any provider before signing an agreement, because moving from one provider to another can be a bit of a hassle.

What Do I Need to Look Out for Technically?

In addition to ensuring that your OS and other processor specific needs are supported, makes sure you review these other items that can be easily overlooked:

1. All the items that you will be “self managing” should be run by your cloud provider. If a simple task requires you to open a trouble ticket, this could be a sign of a missing feature or an immature product, so calculate the risk of wait times for support staff response.

2. If you are working on a disaster recovery scenario, chances are that your existing virtual server instances can’t be just sent to the cloud provider “as is” for use. You may have to build the image from scratch and migrate your data afterward. This is typically the case, as providers need to maintain a special OS build with specific IP addresses for backup and monitoring data that will connect to your OS instance.

3. If you require a database, ensure that the provider will be able to provide enough disk I/O to support your needs. Double check their ability to connect you to a traditional dedicated server, in case you need the processing power to keep up with the application. If you run a clustered database of any type, definitely review this with your provider at length before committing, as many cannot provide a database cluster in the cloud. This is mainly due to the additional VLANs required between the 2 database servers for heartbeat monitoring as well as general I/O issues.

Compatible Cloud Models and Business Needs

Some Cloud providers are geared towards the provision of “full time” applications that will run perpetually in their environment. These tend to be server instances billed daily that can be turned on and off at will. Auto expansion and contraction (of computing resources) may not be part of the service. Other providers price the use of their environment at competitive rates for short term use or bursts, but then don’t seem to be priced competitively for perpetually needed applications. Determine your needs carefully – whether the cloud will be somewhere to which you can send excess load or if you are putting the responsibility of certain applications entirely outside your own data center.

Look for a provider that has an easy-to-understand pricing model and examine where the monthly costs can be easily predicted. Many will provide the ability to assign cost codes to internally bill departments within your firm. Ideally your billing will be done per cloud instance per day or even hourly if available.

It’s a good idea to have a thorough understanding of the scope of services being purchased. Many times the cloud is an infrastructure management-only service. If you are looking for management of the OS and application, this may not be available at all or will come at an additional cost.

Another element to investigate is the timing of instances. You probably want them provided quickly (less than 1 hour) and in an automated fashion. This is certainly in your interest because you can never tell when a project needs an additional server or if late-night testing of an app is required.

Also, you should avoid signing long-term agreements unless there is a large cost savings. This allows you flexibility. Since cloud services use pooled resources, the provider cannot claim to have invested significantly in your specific deployment unless you have dedicated equipment allocated to you.

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  1. S Hill

    Shirin - I agree with most of the comments here - but one should highlight the various delivery models. your mention in brief "Some Cloud providers are geared towards the provision of “full time” applications that will run perpetually in their environment." However, the Monthly type of service lends itself to enterprise application and long term cloud sourcing, while credit card swipe or hourly rate computing is more like app dev and potentially DR services. Additionally, I appreciate the comments about making sure the customer understands OS or application support beyond the infrastructure is either N/A or +$ (e.g. long live MOLO)

  2. Excellent piece - thanks for taking the time to capture everything so nicely Shirin. Taking a slightly longer-term perspective, I believe cloud service provider will ultimately advance and mature enough so that the current technicalities one should be wary of will be a non-issue. In addition, while there may be some gaps in some providers' offerings, the Cloud opens new possibilities to the consumer by leveraging on 3rd-party solutions to augment his/hers provider capabilities. You mentioned the potential need to plan for a clustered database, which I assume is to have HA and scalability. The company I work at, Xeround, offers a Cloud Database service that is designed to provide just that (i.e., a cloud-based, highly-available and elastic database) on top of public clouds. Feel free to check us out at to see how easy it is to have a powerful database set up in minutes.