We all pay our monthly electricity bills. I am sure no one wants to own a power plant 🙂 But, on the contrary most of us own cars and very few rent it for daily use.
The two most important factors which decide how we want to use these two services are –
- The cost of ownership
- The cost and effort in maintenance
Cloud computing today promises benefits (which are similar to using electricity) for computing, hosted application and storage. Although the offer is very lucrative, but their is a dark side to this as well.
The post just tries to some aspects which you must keep in mind before making the plunge.
Most of the services like SimpleDB, EBS, SQS still needs a lot of application integration and porting. And that’s something enterprises hate. It’s one of the primary reasons the X86 architecture and IPV4 are so widely used. Even if someone ports the application to these services, he is guaranteed to be locked with it for the rest of his life 🙂
Services like salesforce.com don’t need any porting, but there have been cases of access to data being refused customers who wish to change the vendor.
Uptime and QoS Guarantees
Most of these services including Amazon and Salesforce do not give uptime and QoS guarantees. The billing and EULA are free from any such clauses.
And when there is a downtime, you can’t do much than start calling the support center to play the blame-game. And its funny when see the the cloud provider talking the same language to its service provider 🙂
It’s No Way Even Close to Perfect
Take a recent unfortunate situation for Ylastic, a company that provides a single front-end to manage Amazon Web Services, who was recently an unwillingly participant in one of these cloud bursts. Ylastic noticed something strange occurring with one of the Amazon Elastic Cloud Compute (EC2) Elastic Block Stores (EBS).
But something wasn’t quite right. And over the course of a few hours the story played out via Twitter as Ylastic noticed issues with its EBS instances. When the problem was finally identified, Ylastic discovered that the data could not be recovered. They were forced to recover from an earlier snapshot, that contained only a subset of the data.
Finally, after recovering what data they could, Ylastic had to go to its customers with the unfortunate message:
“AWS has finally terminated the frozen instances. But the EBS volume is still detaching and has been for hours. It doesn’t seem like we will be able to get into it at this point. Some time in the last month or so, our EBS snapshotting of this stuck volume seems to have stopped working correctly…. We have gone back and run through all the snapshots, and the last good snapshot that we have is from October 1.”
Who was at fault? Amazon? Ylastic? Truly, no one. It was simply a combination of issues. A perfect storm in the cloud, as it were. And that perfect storm resulted in data loss for Ylastic and its customer base.
Take for example the case when you take up a cheap hosted website plan on a shared server. You can still negotiate uptime and QoS guarantees. But, what you just can’t control is a SPAM King sharing the same server and IP address with you 🙂
Most likely you will face two problems –
- A slow response on the website- the SPAM King has taken up the computing
- Public mail servers will mark the mail traffic from you as spam 🙂
Cost of ownership for a power plant is so damn high, that you just can’t afford one even if you are not happy with your power company. That exactly has to be the case for the cloud. No one would think of hosting his own solution when the cloud offers the same peanuts.