Welcome back to my series on migration to the cloud. In my last post we discussed all of the effort you need to put into the planning phase of your migration. In this post we are going to focus on what should happen directly after the migration has been completed.

Regardless of how well you planned or if you just decided to dive right in without any forethought, there are steps that need to be taken after your migration to ensure your application is working properly and performing up to snuff. These steps need to be performed whether you chose to use a public, private or hybrid cloud implementation.

Step 1: Take Your New Cloud Based Application for a Test Drive

Go easy at first and just roll through the functionality as a user would. If it doesn’t work well for you then you know it wont work well when there are a bunch of users hitting it.

Assuming things went well with your functional test it’s time to go bigger. Lay down a load test and see step 2 below.

Step 2: Monitoring is Not the Job of Your Users

If you’re relying on the users of your application to let you know if there are performance or stability issues you are already a major step behind your competition. If you planned properly then you have a monitoring system in place. If you’re just winging it, put in a monitoring system now!!!

Here are the things your monitoring tool should help you understand:

• Architecture and Flow: You design an application architecture to support the type of application you are building. How do you really know if you have deployed the architecture you designed in the first place? How do you know if your application flow changes over time and causes problems? Cloud computing environments are dynamic and can shift at any given time. You need to have a tool in place that let’s you know exactly what happened, when and if it caused any impact.

What happens if you don’t have a flow map? Simple, when there’s a problem you waste a bunch of time trying to figure out what components were involved in the problematic transaction so that you can isolate the problem to the right component.

• Response Times: Slow sucks! You moved to the cloud for many potential reasons but one thing is certain, your users don’t want your application(s) to run slowly. It seems obvious to monitor the response time of your applications but I’m constantly amazed by how many organizations still don’t have this type of monitoring in place for their applications. There are really only 2 options in this category; let your users tell you when (notice I didn’t say if) your application is slow or have a monitoring tool alert you right away.

• Resources: You need to keep an eye on the resources you are consuming in the cloud. New instances of your application can quickly add up to a large expense if your code is inefficient. You need to understand how well your application scales under load and fix the resource hogs so that you can drive better value out of your application as usage increases.

Step 3: Elasticity

Elasticity is a key benefit of migrating your application to the cloud. Traditional application architectures accounted for periodic spikes in workload by permanently over-allocating resources. Put simply, we used to buy a bunch of servers so that we could handle the monthly or yearly spikes in activity. Most of these servers sat nearly idle the rest of the year and generated heat.

If you’re going to take advantage of the inherent elasticity within your cloud environment you need to understand exactly how your application will respond to being overloaded and how your infrastructure adapts to this condition. Cloud providers have tools to execute the dynamic shift in resources but ultimately you need a tool to detect the trigger conditions and then interface with the dynamic provisioning features of your cloud.

The combination of slow transactions AND resource exhaustion would be a great trigger to spin up new application instances. Each condition on its own does not justify adding a new resource.

The point here is that migrating to the cloud is not a magic bullet. You need to know how to use the features that are available and you need the right tools to help you understand exactly when to use those features. You need to stress your new cloud application to the point of failure and understand how to respond BEFORE you set users free on your application. Your users will certainly break your application and during an event is not the proper time to figure out how to manage your application in the cloud.

Let failure be your guide to success. Fail when it doesn’t matter so that you can success when the pressure is on. The cloud auto-scaling features shown in this post are part of AppDynamics Pro 3.7. Click here to start your free trial today.

Application Elasticity, auto-scaling, cloud architecture, Cloud Migration, Cloud Monitoring

Planning to deploy or migrate an application to a cloud environment is a big deal. In my last post we discussed the value of using real business and IT requirements to drive the justification of using a cloud architecture. We also explored the importance of using monitoring information to understand your before and after picture of application performance and overall success.

In this post I am going to dive deeper into the planning phase. You can’t expect to throw a half assed plan in place and just deal with problems as they pop up during an application migration. That will almost certainly result in frustration for the end users, IT staff, and the business who relies upon the application.

In reality, at least 90% of your total project time should be dedicated to planning and at most 10% to the actual implementation. The big question is “What are the most important aspects of the planning phase?”. Here’s my cloud migration planning top 10 list:

1.  Application Portfolio Rationalization  - Let’s face reality for a moment… If you’re in a large enterprise you have multiple apps that perform a very similar business function at some level. Application Portfolio Rationalization is a method of discovering the overlap between your application and consolidating where it makes sense. It’s like spring cleaning for your IT department. You need to get your house in order before you decide to start moving applications or you will just waste a lot of time and money moving duplicate business functionality across your portfolio.
2. Business Justification and Goal Identification – If there is one thing I try to make clear in every blog post it is the fact that you need to justify your activities using business logic. If there is no business driver for a change then why make the change? Even very techie-like activities can be related back to business drivers.
   Example… Techie Activity: Quarterly server patching Business Driver: Failure to patch exposes the business to risk of being hacked which could cause brand damage and loss of revenue.
   I included goal identification with business justification because your goals should align with the business drivers responsible for the change.
3. Current State Architecture Assessment (App and Infra) – This task sounds simple but is really difficult for most companies. Current State Architecture Assessment is all about documenting the actual deployed application components, infrastructure components, and application dependencies. Why is this so difficult? Most enterprises have implemented a CMDB to try and document this information but the CMDB is typically manually populated and updated. What happens in reality is that over time the CMDB is neglected when application and infrastructure changes occur. In order to solve this problem some companies have turned to Automated discovery and dependency mapping tools. These tools are usually agentless so they login to each server and scan for processes, network connections, etc… at pre-defined intervals and create a very detailed mapping that includes all persistent connections to and from each host regardless of whether or not they are application related. The periodic scans also miss the short lived services calls between applications unless the scan happens to be at approximately the same time of the transient application call. An agent based APM tool covers all the gaps associated with these other methods.
   

   How well do you know the current architecture and dependencies of your application?

4. Current State Performance Assessment – Traditional monitoring metrics (CPU, Memory, Disk I/O, Network I/O, etc…) will help you size your cloud environment but tell you nothing about the actual application performance. The important performance metrics encompass end user response time, business transaction response time, external service response time, error and exception rates, transaction throughput, with baselines for each. This is also a good time to make sure there are no glaring performance issues that you are going to promote into your cloud environment. It’s better to fix any known issues before you migrate as the extra complexity of the cloud can amplify your application problems.
   

   You don’t want to carry application problems into your new environment.

5. Architectural Change Impact Assessment – Now that you know what your real application and infrastructure components are, you need to assess the impact of the difference between traditional and cloud architectures. Are there components that wont work well (or at all) in a cloud architecture? Are code changes required to take advantage of the dynamic features available in your cloud of choice? You need to have a very good understanding of how your application works today and how you want it to work after migration and plan accordingly.
6. Problem Resolution Planning – Problem resolution planning is about making a commitment to your monitoring tools and strategy as a core layer of your overall application architecture. The number of potential points of failure increases dramatically from traditional to cloud environments due to increased virtualization and dynamic scaling. In highly distributed applications you need monitoring tools that will tell you exactly where problems are occurring or you will spend too much time isolating the problem location. Make monitoring a part of your application deployment and support culture!!!
7. Process re-alignment – Just hearing the word “process” makes me cringe and have flashbacks to the giant, bloated , slow moving enterprise environments that I used to call my workplace. The unfortunate truth is that we really do need solid processes if we want to maintain order and have any chance of managing a large environment in a sustainable fashion. Many of the traditional IT development and operations processes need to be modified when we migrate to the cloud so you can’t overlook this task.
8. Application re-development – The fruits of your Architectural Change Impact Assessment work will probably precipitate some level of development work within your application. Maybe only minor tweaks are required, maybe significant portions of your code need to change, maybe this application should never have been selected as a cloud migration candidate. If you need to change the application code you need to test it all over again and measure the performance.
9. Application Functional and Performance Testing – No surprises here, after the code has been modified to function as intended with your cloud deployment it needs to be tested. APM tools really speed up the testing process since they show you the root of your performance problems down to the line of code level. If you rely only upon the output of your application testing suite your developers will spend hours trying to figure out what code to change instead of minutes fixing the problematic code.
   

   Know exactly where the problem is whether it is in your code or an external service.

10. Training (New Processes and Technology) – With all of those new and/or modified processes and new software required to support your cloud application training is imperative. Never forget the “people” part of “people, process, technology”.

There’s a lot more that really goes into planning a cloud migration but these major tasks are the big ones in my book. Give these 10 tasks the attention they deserve and the odds will shift in your favor for a successful cloud migration. Next week we’ll talk about important work that should happen after your application gets migrated.

application testing, Cloud Migration, current state assessment, performance testing, Problem Resolution

Welcome back to my blog series on deploying applications to the cloud.

What’s the point of deploying an application to the cloud versus just hosting it in your own data center? Is it really a good idea? Will it save you money? Will it work better? Will it cause new deployment and management problems? How do you monitor it?

These are all basic questions you should ask yourself before deciding IF your new or existing application will end up in a cloud environment.

The answers might be different for each application supporting your business. Cloud is really a set of architectural patterns that are available to help you solve business problems using technology. If you’re considering cloud you better have a business problem that you need to solve.

Here are a few business problems that would make me consider a cloud implementation for my application(s):

• We’re out of space in our data center and most of our applications are used via the internet–should we build another data center or move some applications to public cloud providers?
• Our new mobile application will need to scale rapidly as it becomes more popular–we have to be able to scale as needed so our customers have a good user experience.
• We need to accelerate our time to market and make our business more agile–we don’t have time to wait for IT and all of our productivity sapping processes.

No matter what your business reasons are you need to come up with quantifiable and measurable success criteria so that you can prove out the benefits (or failure) of your cloud computing initiative. This implies you are already measuring something BEFORE you move to the cloud so you can compare metrics before and after. Here are some example KPIs that might be applicable:

• Time to deliver requested environment to developers
• Number of application impact incidents
• Infrastructure cost per application
• Time to scale / Cost to scale Application
• Transaction throughput
• SLA (yeah, you really should have one of these)

So You’ve Decided To Go For It

You’ve got your business justification nailed down and decided you really do need a cloud based application. Great! If this is a brand new application you can design it from the ground up and just deploy it, right? No!!! Remember, you need to monitor and manage this application if you stand any chance of providing a good user experience over the long haul.

“My cloud provider has all the monitoring and management tools I need.” – Wrong! Your cloud provider has basic monitoring tools that show you infrastructure metrics (CPU usage, Memory Usage, I/O usage, etc…). These monitoring tools don’t tell you anything about your application. Here’s what you need to know about your cloud application (at a minimum):

• Which application nodes are in use at any given time. (Dynamic scaling, provisioning, de-provisioning will change this picture at any given time)
  
• Application calls to external services with response times and error rates. (External service calls are performance killers for cloud applications and drive up the cost as most provider charge for network traffic leaving their cloud)
• The response time and errors of all of my users business transactions. (Applies to any application architecture but cloud deployments can experience greater variance due to factors outside of the application owners control (network congestion, regional provider issues, etc…))
• When a problem occurs – full application call stack for code analysis. (Applies to any application architecture)
• Host level KPIs correlated with all of the application activity. (Really important in the cloud due to host virtualization, shared resources, and multiple sizing options when you select a host to deploy. Select the wrong size by mistake and you just limited your max application performance)
• Historic baselines for everything so you know what normal behavior looks like. (Critical to identifying problems regardless of architecture)

If you’re deploying a new application you should have a really good idea of any external application dependencies (like calling a payment gateway to process credit card orders). If you are moving an existing application there is more work that needs to be done up front. In particular you need to really understand your existing application dependencies. Is there a service or backend database that your application relies upon that you’re not planning to move with the application? If so you can really screw up the entire cloud implementation if you make a bunch of calls to a component that lives outside of your chosen cloud environment.

Modern applications have many external dependencies. You absolutely MUST know what they are before moving to the cloud.

If you’re moving an existing application you better deploy a tool that can dynamically detect and show application flow maps. I’m not talking about those agentless tools that scan your hosts everyday looking for network connections (those usually miss all of the short lived services calls). I mean a solution that will give you the entire picture regardless of persistent and transient connection methodologies.

Since you need to monitor your existing environment anyway you might as well collect performance data and save it so that you have a good point of comparison for your “before and after” application environment (We’ll discuss this item more in a future blog post).

There are a ton of considerations when you choose to implement your application using cloud computing architecture patterns. In my next post I’ll go into more detail around the planning phase. Having all your ducks in a row before your begin the migration is critical to success.

cloud, Cloud Applications, Cloud Migration, IaaS, PaaS

I get so many questions about cloud computing from friends, acquaintances and IT professionals alike. The non-technical folks usually have heard of “the cloud” but have absolutely no idea what it is or even realize how much they interact with it on a daily basis. They don’t realize that their email, phones, videos, music, online games, etc… are probably hosted on or rely upon cloud based services.

The Technology crowd on the other hand knows a good bit more about cloud computing but there is a huge disparity in the understanding of what cloud is really about and how it really works. Many IT professions I have spoken with have trouble explaining the major differences between IaaS, PaaS, and SaaS (and unfortunately some don’t even know what the acronyms stand for).

The problem is that cloud computing, though quite pervasive in the consumer market, is still very mysterious to the enterprise market. The people who keep enterprise IT up and running have their hands full just making sure their applications are up and performing well. It’s not like they can just go to some single day cloud computing training session and magically be imbued with all the knowledge required to implement and manage a cloud of their own. Like most other things in life it takes hands on experience and a lot of time to get really good at implementing and managing cloud applications. But there is shortcut you can take, read on…

By using the right tools and having someone help you with the right processes, you can be much more effective than you otherwise would have been. Tools basically encapsulate other peoples expert knowledge and help you do greater things than you are capable of on your own (as long as you use them properly). Processes are intended to help you get the most out of your tools and people.

In my last post I said we would discuss how to decide if your application should move to the cloud and how to monitor your cloud application so that you didn’t adversely impact your users. This post is long enough for today so I will leave those topics for next time (I promise).

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