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07.29.2011

For many of the old timers in the mainframe world, the word cloud alone will get you an eye roll or two. They will tell you that it is just a new word for a function that mainframes have been performing for years. But is it?

Sure, there are many that claim that it is nothing more than a resource made available in a company with security and solid management controls that is dynamically provisioned, in other words a mainframe. But what seems to be missing from this definition is user control. And most experts will tell you that it is a key attribute of cloud hosting.

And one of the key characteristics that gives mainframes their reputation as old technology is the very controlled environment that makes it so secure. An administrator is needed to provision computing power for any specific task, unlike in the cloud technology. And this is why x86-based distributed architecture is the mainstay for cloud computing and not mainframes.

Even with this reasoning, mainframe vendors still claim that as many as 73% of their clients are looking to use their mainframes as part of the move to the cloud. In fact, IBM has been advocating for mainframes as cloud platforms the last several years, especially since the introduction of the zEnterprise last year. IBM introduced virtual operating systems over 30 years ago and with the addition of Linux, running virtual X86 servers on their mainframes was a logical next step.

But the problem of self-provisioning remains. When you have a system where in some companies the mainframe is in a locked room where no one can access it, it is hard to see how to develop self-service features. IBM’s system x cloud computing leader, Reed Mullen, claims that the problem Is a reflection of the culture of mainframes, not the technology. But even Mullen admits that any implementations are still going to be run through IT, probably via a request email to have resources allocated. Point and click allocations don’t seem to be part of the picture.

One scenario where mainframes as cloud platforms may be happening now is worldwide outsourcing companies with developers spread across the globe. These developers would have the ability to set up their own testing and development platforms, and some may be mainframe based. Mullen of IBM agrees this is the most likely situation with today’s technology and says it “is perhaps the dominant usage of a cloud infrastructure in mainframe environments today.”

As the cloud matures more situations may develop that will lead to a wider adaptation of mainframes to cloud platforms, but for now the ability still seems somewhat limited. But no matter how you look at it, the development of business units to self-provision a mainframe-based cloud is coming. It will probably change the way mainframes are seen as they run more of the same software and grow their service-management side. They may soon be seen as just another high-end element in the cloud world, instead of a class on their own.

Our newsletters and blogs are written to provide you with tools and information to meet your IT and cloud solution needs. We invite you to engage in our online community by following us on Twitter @GMOCloud and ‘Liking’ us on Facebook.

07.25.2011

One of the elements that have been closely discussed with the introduction of cloud hosting is multi-tenancy. This is when more than one non-related resource is allocated on the same hardware. A good example of this are VM instances that are running on the same servers sharing CPUs, memory and network adaptors. In the case of SaaS (Software as a Service), multi-tenancy is created when your have more than one client sharing the same application while making sure that the data is properly partitioned.

But when you have a tenant who behaves badly, the other tenants who act in good faith can find themselves starved out when there are controls lacking to limit the consumption habits of their neighbors. Sadly, this can happen all too easily. Often the limits are not enforced when the hosts believe they can easily scale up or down as needs arise. This is, after all, one of the big promises of cloud hosting.

Unfortunately, not all resources are created equal and so they also do not scale equally. Any re-allocations from the pool could result in a negative impact on the other tenants’ ability to scale as well. The area that is often forgotten in this scenario is bandwidth. While CPU time or memory can quite easily be controlled, the bandwidth process can be much harder to control for each tenant. Sometimes this can result in a denial of service to other tenants because they are sharing the same switch or running on the same network adaptor.

It is important for any cloud adaptor to remember that anything in the cloud needs bandwidth. So in addition to taking care of client requests, your client requests generate traffic which consumes bandwidth. In the end it doesn’t really matter if the traffic is created by communication with the storage network, database, or application servers. You could have the hypervisor substrate reallocating and balancing loads, they all take up bandwidth. The bottom line is there are limitations to the network, physical ones that can be as simple as fiber-based connections. It is rare for anyone to measure or understand the aggregate network load created by one tenant within the multi-tenant architecture and in many situations being able to directly access a particular network load may not even be possible.

So beyond how this affects performance, why should we care? Well, if you are designing solutions for the cloud, you need to be sure that you test your production environment’s real operating performance and not just count on the specs given by your host provider. A machine instance with two-cores operating at 2.5Ghz, 2048 megabytes of RAM, 500 gigabytes of disk space and 1 gigabyte network adapter does not equate 1:1 performance. Testing is imperative while the application is running in this environment. Of course, you still cannot assume it will run in real life the way it ran in a test environment. So be sure to also obtain average IOPS for storage, and average bandwidth over a reasonable amount of time, and always look at your response times around key processes. This should give you the minimum needed to assess.

Our newsletters and blogs are written to provide you with tools and information to meet your IT and cloud solution needs. We invite you to engage in our online community by following us on Twitter @GMOCloud and ‘Liking’ us on Facebook.

07.14.2011

As cloud adaptation quickly moves into business, IT Department Heads must learn how to prepare for changes in technology and staff or suffer the consequences. Here are a few pointers to help prepare for that move to the cloud in today’s IT world.

Prepare for the shift
Don’t assume you can just move everything to the cloud. Plan how your department will strategize to make organizational improvements to align your department with the cloud.

Restructure IT and Manage the Cloud
Don’t let management be seduced by the accessibility of the cloud. Be sure that your department is still the go to expert of all things IT, including the cloud.

Extend IT influence
With the cloud removing the IT department as simply maintenance, now is the time to establish the department’s place regarding strategy and business critical initiatives.

Make use of traditional outsourcing skills
This is one area where IT already should have skills, and working with the cloud has many similarities to the role of product and service evaluation, contract negotiations and performance monitoring that were needed before.

Reduce IT risk by adjusting your organizational design

Maintain control of the technology decision making process by making adjustments to your organizational design to align IT with the cloud.

Manage the cloud as part of IT structure
Take an active role in managing the cloud by deciding which services should migrate to the cloud and which should stay in-house. Create a hybrid environment that is the best of two worlds.

Our newsletters and blogs are written to provide you with tools and information to meet your IT and cloud solution needs. We invite you to engage in our online community by following us on Twitter @GMOCloud and ‘Liking’ us on Facebook.