Cloud - quick explanation pleasr

[EagleKeeper]

I am seeing job ads for software engineers with Cloud experience.

What exactly is the Cloud other than a distributed storage area and possible computing power?

What makes a s/w engineer a cloud expert and how can one develop enough knowledge to chase this work?

 

[KentState]

Sounds like someone wanted to through a buzz word in there to make the job sound cutting edge. Cloud can mean so many different things depending on what service the company provides. If they are a cloud service provider, it may be something different than a private company trying to push application to the cloud.

 

[esun]

Well there are two cases here: those developing applications to run on cloud infrastructure, and those actually developing the cloud infrastructure.

In reality they probably are looking for experience in developing applications that run on something like Amazon AWS, Microsoft Azure, Rackspace, or whatever else is out there.

For companies actually developing cloud infrastructure, then experience with something like OpenStack would probably be the focus rather than just application development.

 

[DaveSimmons]

FYI, Amazon offers free tiny server instances, and MSDN / Visual Studio comes with some free Azure time.

Amazon is the leader if you aren't using MS' software stack. They offer server instances (think VMs) and the structure to add / remove instances automatically based on load and health checks; Database servers and replication, load balances, storage space that's separate from the page / app servers, DNS servers.

The "cloud" part is getting used to writing code for multiple, disposable page / app server instances, tied to one or more database instances, with file storage also separated from the app servers.

It's similar to developing for local server clusters in that you can't use local data files for storage except during a single request. The next request from the user might hit a different server in the cluster, where the files you just created don't exist.

PS - with Amazon the VMs / server instances can be several flavors of linux, or other OSs including Windows Server. You can modify stock server instances by installing the packages of your choice, then store an image of the modified server to their storage for later use. This means you can run pretty much anything you want, PHP + add-ons, Tomcat and JSPs, Windows and ASP.NET, etc.

 

[exdeath]

Can you make a web application that populates a late binding combo box with 37 bytes/5 items and make it take more than 30 seconds?

Grats, you can write cloud apps.

Bonus points if it freezes the entire browser while it does it.

Give me a hard binary client any day over this cloud crap.

 

[Markbnj]

I think its probably closest to what Dave described, but yeah, it's almost too much of a buzzword to be useful.

 

[DaveSimmons]

Like "web services" and "xml data file" before it

(If a file is "in XML", then any "XML aware" program can parse it and do something useful with the data, right?)

The big change in thinking (to me anyway) is that the server VMs are scalable, disposable and interchangeable. If one fails its health check, the monitoring program kills it and loads a replacement. If the load on one gets too high, the program adds more as needed until the peak period is over then kills them off. The other change is in having different services for application / page processing, database and storage, but that's probably old hat to corporate developers.

A few years ago we had a web-based application running on several dedicated servers rented from hosting companies. With that, if the server disk or motherboard dies on you, you have to put in a ticket, wait for them to fix the server or assign you a new one, then re-load your data, settings, and applications. We weren't paying the (high) fees for a hardware load balancer so we manually assigned customers to the different servers, and manually shifted them as needed. Amazon's approach works much better for this kind of usage, and is much cheaper too.

 

[Markbnj]

(If a file is "in XML", then any "XML aware" program can parse it and do something useful with the data, right?)

Ha, yes, because XML data is "self-descriptive" and therefore any old code that is capable of parsing human language and understanding its context should be able to make use of it.

 

[mv2devnull]

Cloud is just one form of outsourcing. There are various clouds though. One may give you keys to OpenStack while other just hides behind the Save-button of your Office. Client-server could be called cloud as well.

 

[Apathetic]

"The Cloud" is simply a buzzword that means "someone else's datacenter". There is nothing magical or new about it (other than the hype).

Dave

 

[Train]

"The Cloud" is simply a buzzword that means "someone else's datacenter". There is nothing magical or new about it (other than the hype).

Dave

Uhh no. Dedicated hosting is not cloud. Neither is managed hosting, both of which existed long before cloud computing.

Cloud refers to on demand virtualization. There are distinct differences.

 

[Train]

Can you make a web application that populates a late binding combo box with 37 bytes/5 items and make it take more than 30 seconds?

Grats, you can write cloud apps.

Bonus points if it freezes the entire browser while it does it.

Give me a hard binary client any day over this cloud crap.

How is a binary client going to make the response from a web service faster? Most binary clients talk to... gasp, cloud based services.

 

[Apathetic]

Uhh no. Dedicated hosting is not cloud. Neither is managed hosting, both of which existed long before cloud computing.

Cloud refers to on demand virtualization. There are distinct differences.

And where does this take place? Bottom line, it takes place in a data center using the same technology we've had for a long time now. Anytime you're reading some marketing crap about "The Cloud", just substitute those two words with "someone else's datacenter" and you'll have a good idea about what's going on.

Dave

 

[Train]

And where does this take place? Bottom line, it takes place in a data center using the same technology we've had for a long time now. Anytime you're reading some marketing crap about "The Cloud", just substitute those two words with "someone else's datacenter" and you'll have a good idea about what's going on.

Dave

You completely missed the point of my response. Who owns the data center is irrelevant. you could technically set up a "private cloud"

Dedicated servers, managed hosting, traditional virtual machines= NOT CLOUD, the same holds true whether this is in your data center or someone else's.

Virtual services that can be spun up and down dynamically = cloud. This is why amazon originally called it "elastic services" before the cloud term caught on.

 

[Train]

Another benefit of a cloud service is you can seamlessly span multiple data centers.

Microsoft's content delivery network, for example, can automatically and dynamically cache your files in various data centers, and even on different continents, to meet changing traffic demands. Then when the files are not requested for a while (the cache expires), the staged copies start getting deleted, essentially shrinking your hosted storage back down to the few "hard copies"

 

[DaveSimmons]

^ that can be a huge deal. Backhoes cut data cables, snowstorms, fires, floods or earthquakes can take out entire data centers.

Before Amazon, we would have dedicated servers in 2-3 data centers, but customer migration and database sharing was not seamless the way it is with cloud services.

 

[bobross419]

Cloud also offers the ability to quickly scale your environment. If you normally get 2-3000 hits per day and you find out you're going to be on the Today Show tomorrow, how is your little server going to handle all the traffic sent its way? In a well configured cloud environment you can just quickly spin up a few dozen (or hundred) servers in a few minutes and not have to worry about your server failing.

There are things that we'll always need dedicated hardware for, but there are a lot of cost savings available with cloud services if you know what you're doing. You might need 4 cores and 8G of RAM to handle traffic on your site from 4pm-8pm every night, but only 1Core and 2G the rest of the day... just pay for the extra stuff in the evenings and not all day.

These are just a few examples of benefits of cloud. I'm not saying there aren't things that dedicated does better, but for a lot of things cloud is more than sufficient and usually cheaper.

Theres a lot of FUD about cloud floating around anandtech. You guys should really invest some time into learning about this stuff before blatantly dismissing it.

 

[Markbnj]

Theres a lot of FUD about cloud floating around anandtech. You guys should really invest some time into learning about this stuff before blatantly dismissing it.

It's a buzzword to me. All the specific technologies that people have mentioned as falling under the 'cloud' umbrella are vital and useful, and have their own nomenclature and concepts. The word 'cloud' doesn't tell me much of use, other than that it probably refers to some resource that is out there on the network somewhere.

 

[bobross419]

While I agree that its very often just used as a buzzword, the reality of the cloud is actually quite exciting.

NIST's definition does pretty well in summing up what should actually be considered to be cloud -- http://csrc.nist.gov/publications/nistpubs/800-145/SP800-145.pdf

The definition is expansive enough to cover things like Gmail and Dropbox (SaaS), but when you get into IaaS things are dramatically different. SaaS is nice for non-techies, IaaS can be pretty hard core. A good cloud developer could do something like monitor the server load on a web head and submit an API call to spin up another server behind the load balancer if load goes over 1 (or connection count exceeds 1000, or apache processes are within 5% of MaxClients). This is something you just can't do with dedicated hardware.

 

[Cerb]

A good cloud developer could do something like monitor the server load on a web head and submit an API call to spin up another server behind the load balancer if load goes over 1 (or connection count exceeds 1000, or apache processes are within 5% of MaxClients). This is something you just can't do with dedicated hardware.

You don't have to be a good developer at all, for that. Any code monkey could get that set up.

The bottleneck there is that you have to decide to pay for the added servers, which is not a developer issue. The issue there is that you need your main management, bean counter(s), admins, programmers, and infrastructure providers to all be on the same page wrt to the issue, and make a distinct point to implement it as an automatic feature. It's not a problem that would be hard for a developer, so much as it is being willing to make a decision in which program behavior can add to your costs, without management making a specific decision to spend that money.

I'm sure some SaaS providers have exactly that going on, once they're sure that the load will only be increased when it involves more paying customers.

With dedicated hardware, you tune your storage so that you don't need to do that, with low-utilization servers, and/or cold/warm spares, if keeping them on and ready all the time costs too much. Once you're paying for redundant A/C units, a dedicated room, redundant internet with a SLA, etc., having more server capacity than you think you'll need is cheap. It's not that you can't handle higher load (marketing crap!), but that handling real loads in-house involves a significant expenditure up-front (possibly so with a colo, as well, even beyond the servers), where IaaS providers will give you operational costs only (capex v. opex).