Thursday, May 25, 2017

What do I need to consider when integrating Public Cloud? The Hybrid Conundrum: Part 2

Integrating a Public Cloud option into your Enterprise environment is not unlike integrating a new datacenter. Lighting up a new datacenter requires certain components to be in place before services are available. For example; core services such as networking, interconnectivity and Active Directory and Role Based Access Control “RBAC” should be reviewed and configured. RBAC determines who is able to access the environment and what they are able to do. In our discussions with customers we call these Public Cloud Foundational services.

While this is a very simplified list, it can be complex. For example consider backup, DR and monitoring when building a Hybrid environment. Often we have very established ways of doing these things in the enterprise and ideally a single framework for management. Public Cloud Providers offer alternatives to these Enterprise solutions that are optimized and tightly integrated into the platform. For example: does it make sense to apply your same standard backup solution to workloads in the Cloud or should you consider the Public provider alternative?

Once the foundational services are in place, you are ready to consider the migration. Migration to Public Cloud is a little different than “Lifting and Shifting” a workload. In Enterprise virtualization environments, the infrastructure looks after the application resiliency. In Public Cloud the application architecture needs to manage resiliency and availability of the app. This means that each individual application is its own micro-architecture. While you may be able to lift and shift some workloads, others may need to be redesigned into the Public Cloud.

Failure to carefully consider  the migration approach may lead to decreased availability of the application in the Cloud. For example, Azure has a Service Level Agreement of three 9’s (99.9 percent uptime) based on an Availability Set in Infrastructure as a Service “IaaS”. An Availability Set consists of two or more virtual workloads running on separate host hypervisors. When Microsoft patches the host hypervisors they guarantee that they will not reboot the virtual workloads at the same time to meet the SLA. If you are running on a single instance however you will experience outages.

The number of applications that will need re-architecting can have a dramatic impact on your migration timeframe. Understanding the percentage of applications that you have that are truly Cloud ready allows you to create two migration streams. One that moves quickly with the ideal Cloud candidates and the other that reviews whether the application should be replaced, re-architected or perhaps remain in the enterprise environment.

The key to success is in placing the applications in the environment that delivers the best business value. As the environment will be a hybrid of enterprise and public, it is more important to align them then it is to move them to cloud for the sake of moving them. Surprisingly, while obvious, many strategies often take an all or nothing approach. The “We are moving everything to Cloud” mantra should be “We are Cloud enabling our core business applications while maintaining others in the Enterprise”.

In the next post we will have a brief look at the operational and management considerations pre and post migration.

Tuesday, May 16, 2017

What do I need to consider when integrating Public Cloud? The Hybrid Conundrum: Part 1

Having worked through these challenges with various customers, I thought it would be a good idea to share. When integrating Public Cloud there are a number of “should and should not's” that warrant some consideration.

Perhaps the first and foremost is what goes where? Private, Public or managed by a 3rd party? For those of you who remember the early days of virtualization you likely remember capacity assessments which described what was needed to virtualize a set workload. While the information required has changed, the process is very similar. Today’s assessment software from vendors like Cloudamize take a similar workload assessment approach but provide a different set of outputs that are important to Cloud.

Optimizing the workload is still very important as even with virtualization we tend to over assign resources. In Public Cloud every excess is a price point so right sizing performance has a direct association to the cost. In addition, in Public Cloud when you build a virtual instance it is a layering of components that each have a specific performance characteristic. For example, in Public Cloud you have different storage performance tiers on which to add different virtual instance classes that are predefined with a set number of CPUs and memory configuration. Building without performance input leads to virtual instances that may under perform or cost to much.

Because Virtual instances are sold by certain T-Shirt sizes or classes in Public Cloud, having a tool like Cloudamize to translate from a VMware VM to an Azure Virtual instance class can be a great starting point. One of the other characteristics of Public Cloud providers is while they are very accommodating of ingress traffic (traffic coming in) they typically charge for most egress traffic (traffic coming out).

If we think of our business applications as a bunch of chatty VMs it is important to know who is talking to who. This allows us to ensure that all application interdependencies can be migrated together. This cuts down on the cost and flow of egress traffic between the Public Cloud and the Enterprise datacenter. This is another capability of a good assessment tool; the ability to identify related application traffic flow between a group of VMs.

Having a look at the relationships between the VMs and applications allows us to consider whether it should run in the Enterprise or on Public Cloud. Often this requires a look at the empirical data along with some reasoning. For example, if I have a legacy application that I will continue to use until I cutover to a new Cloud based application, should I migrate it to Public Cloud? If I have VMs providing backup services in the Enterprise should these migrate? What order and what things do I need in place for the actual migration? We will have a look at these more carefully in my next post @podoherty.