In a previous post, Sara and Daniel helped us to learn about the different cloud computing options that providers offer us, but how to move from using my servers to using cloud services?
Maybe Daniel and Sara can help us today as well.
Daniel currently lives with his brothers in an old country house in a village on top of a mountain, but there are important changes in Daniel’s life; this month he has been offered a job in Bernede, a city far away from where he currently lives. Despite being far from home, the position is very interesting, and he has accepted it, but the bad news is that he has nowhere to live there. For the time being, he has opted to rent a small apartment that is very nice and modern but has no furniture. Daniel’s idea is to go back to the village on weekends and stay the rest of the week while he works in Benerde. Instead of buying all the furniture and paying for it all, what he is going to do is make a list of the things he needs and see what he can take advantage of what he has in the village by asking his brothers if they need it or not, and then see what he should buy.
Sara has been told that the company’s strategy is to reduce costs and migrate applications (workloads) as much as possible to the cloud. But how? The first thing Sara and her team have done is to make a list of the current applications and analyze their use, if they are already planned to be decommissioned, their level of importance for the business, etc. and with this information they will decide the strategy to follow with each one of them. The best-known migration strategies are the 6 R’s of AWS (or 7 R’s). So Sara is ready to classify the applications taking into account these strategies.
To make the list of furniture he needs, Daniel has been going through his current house and checking in each room if there would be something he would need from there. The truth is that it has been very good for him, because he has realized that he had some furniture and things that he did not use and that were a little old, so he has taken advantage and has done some cleaning, throwing away all these old things and freeing up space in his house. In addition, he has seen some objects that, although they can be useful in his new house, he thinks they can be more useful when he comes back on weekends, for example the easel he uses to paint pictures, he does not think he will use it during the week and it would also take up space, so he decided to leave it in his village.
At Sara’s company, they are also analyzing the list of applications they currently have and reviewing their status and what they should do with each one of them. In the review they have detected some applications that are obsolete and not worth keeping; that is why they have decided to remove them. Here we have the first strategy: Retire, dismantle, or remove applications that are no longer needed in the company.
As part of the analysis, they have also detected some applications that, despite being in disuse, still have some time left to be retired or others that their migration to the cloud would be very complex and costly (or that the law does not allow it), so they will keep them in their data center and will not migrate them. This is the second strategy: Retain (also known as revisit), keep the applications in the source environment.
Meanwhile, Daniel has found a bedside table in his house that could be useful for him. It is a piece of furniture that is not the style of the new apartment but knowing that he is going to have to spend money on other things and that he wants to move as soon as possible, he decides to take it to Bernede, just as it is. He has also seen the need to take some chairs and a table from the dining room, and in the attic, he has found them, but they are not the style of the apartment either, since they are green chairs and tables and the dining room of Bernede’s apartment is blue; Daniel likes handicrafts, so he decides that before taking them, he will remove the green color and paint them blue, the style of the chairs is still old, but the color at least fits the style with the dining room and will make it look much better. In other words, he will modify the furniture a little before taking it with him to adjust it a little to his new apartment, it is not ideal, but it is functional and better than green.
Continuing with the analysis of the applications, Sara’s company has seen that some applications that they currently have on premise, can be moved to the cloud without any changes, for example provisioning hardware in the cloud, where to move our applications and instead of running on an operating system hosted on our servers, the application would run on operating systems of systems hosted in the cloud provider, in other words, we would be using IaaS. In this case we are presented with the third migration strategy: Rehost (also known as lift and shift), move an application to the cloud without making any changes and taking advantage of cloud capabilities such vertical scaling.
Other applications, however, need minor modifications to be able to be run on the cloud provider to take better advantage of the capabilities offered, for example changing database connections, changing services performed by hand to services available on the cloud provider, etc. The fourth migration strategy would then be: Replatform (also known as lift and reshape), move an application to the cloud and introduce some level of optimization and taking advantage of cloud capabilities such new services.
It’s time for the appliances, Daniel has started to review what he would need and has come to the conclusion that he would need a place to cook, a refrigerator and a washing machine. For cooking, the apartment already has a ceramic hob and microwave oven that will allow him to continue making pizzas if he feels like it; the problem lies in the refrigerator and the washing machine.
In the case of the refrigerator, he has chosen to buy a new one, since there is a space in the kitchen predestined for a very specific size of refrigerator, and since he wants it to fit well, he will buy it in that size. In the case of the washing machine, there is no space, and he has also thought that, if he is going to return to his house in the village almost every weekend, he can take advantage and bring the clothes to wash so he will not use the washing machine much. And in case he needs to clean something urgently, he can take advantage of a laundry near his apartment, where in addition to washing they also iron the clothes and with home service, so he saves the washing machine, the iron and having to take care of the laundry. What more could he ask for?
Sara and her team have seen that there are some applications that are worth upgrading, such as the ordering portal that usually gives many connection problems and failures to respond when many users connect and especially in times of campaigns like Christmas, but they could not buy more powerful systems because they were too expensive. Since they are very interested in e-commerce, the order portal is going to be redeveloped, thinking about the new capabilities that the cloud provider offers as improvements in scalability and greater resilience among others, a clear example of the use of the cloud as a PaaS. This migration strategy would be: Refactor/re-architect, move an application modifying its architecture while taking full advantage of cloud-native features to improve agility, scalability and performance.
One application that they have seen that is also very outdated and does not reflect the new developments available is the customer and marketing campaign management application. When they have reviewed what it would cost to implement it again, they have realized that it is very expensive and there are solutions already available in the cloud that will allow them to perform these tasks, so they have decided not to create from scratch the application, but to use this cloud software already available in SaaS mode, paying only for what they need. This migration strategy is: Repurchase (also known as drop and shop), move to a different product, normally by moving from a traditional license to a SaaS model.
Daniel has been thinking for a few days what to do with his aquarium. Daniel has an aquarium that he looks at because it relaxes him a lot, and he is sad to leave it in the village; finally, he has decided to take it with him. Somehow, the fish are not going to change house, since they will continue living in their aquarium, but the aquarium will change house, being its new location the apartment in Bernede.
Sara has found some applications that are currently running on virtual machines, but due to hardware issues, they have not always scaled as much as they would like, that is why they will also migrate them to the cloud. In this case, the applications will continue to run on their virtual machines, but these virtual machines will not run on Sara’s data center hardware, but will run on the cloud provider’s hardware, having access to better resources on demand. This type of strategy is called: Relocate (also known as hypervisor-level lift and shift) — Move infrastructure to the cloud without the need to rewrite applications or purchase new hardware.
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With this we have reviewed the migration strategies, also known as Amazon’s 6 R’s (7 R’s). Reviewing they would be:
- Retire: dismantle, or remove applications that are no longer needed in the company.
- Retain (also known as revisit): keep the applications in the source environment.
- Rehost (also known as lift and shift): move an application to the cloud without making any changes and taking advantage of cloud capabilities such vertical scaling.
- Replatform (also known as lift and reshape): move an application to the cloud and introduce some level of optimization and taking advantage of cloud capabilities such new services.
- Refactor/re-architect: move an application modifying its architecture while taking full advantage of cloud-native features to improve agility, scalability and performance.
- Repurchase (also known as drop and shop): move to a different product, normally by moving from a traditional license to a SaaS model.
- Relocate: Move virtualized infrastructure to the cloud with no changes required. This last migration strategy is the one that is not considered when we talk about the 6 R’s. It is a strategy that is only available from some cloud providers along with specific machine virtualization technology providers.
I hope this little article has been able to clarify some doubts about application migration strategies to cloud providers, I also hope Daniel is doing well in his new apartment, which by the way, don’t tell Daniel, but it is very close to Sara’s apartment.
Waiting for the trilogy
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