The process of migration is called so because it appears to be the method of pulling data from a traditional server to the cloud cluster. The scale of data brought from one type of platform to another might drastically differ. Some companies and developer teams transfer one or few applications. And some transfer the whole infrastructure that is already established on some sort of hosting.
Let us begin with different types of migration. There are three main sorts:
Transferring "as it is" (without any distinctive data changes).
Rebuilding.
Hybrid transferring.
Cloud migration of this type is the simplest way of pulling data from traditional servers to cloud clusters. The idea behind the process is straightforward: you simply take files, configurations, etc. and put them into the cloud using a special service. All settings are kept the same, as well as the installed applications. Everything can be run using virtual machines.
It is quite easy to automate the process for this kind of migration. There are special applications that can copy the data to the cloud server without any interference from the user's side. Such an approach increases the level of reliability and makes it easier to control the entire system.
But there's at least one huge disadvantage of transferring "as it is": it prevents you from using the full potential of cloud clusters.
This is a migration of infrastructure from traditional servers to the cloud and has all the technical advantages that cloud systems possess. As might be expected, rebuilding is a harder task than transferring without data and parameter changes. While rebuilding you have to rewrite your monolith apps dividing them into microservices.
Furthermore, you must change some elements of infrastructure whilst rebuilding. For instance, lots of companies and development teams decide to drop manual DBMS support and switch to controlled databases. That's why there are more and more providers who offer such DBs.
Resettlement of the whole infrastructure noticeably increases its efficiency. You will experience a more flexible and powerful way of working with your data making it much easier to test applications, scale them up and release new features.
Hybrid migration might be considered a "something in between" solution. It has some trade-offs but generally fits the best. It works in the following manner: you transfer your data "as it is". The whole infrastructure is pulled to the cloud without perceptible changes. After that, the rebuilding takes effect, so moved infrastructure becomes more compatible with cloud services.
Migration can be implemented on various levels. If you want to understand the difference between these levels better, you'll need to differentiate between IaaS, PaaS and SaaS.
IaaS stands for Infrastructure as a service.
PaaS stands for Platform as a service
SaaS stands for Software as a service.
There is a popular comparison of these technologies with pizza. It goes as follows: if a person buys ingredients for pizza and makes it at home himself — it is IaaS. If a person orders a pizza and eats it at home — it is a PaaS. If a person orders a pizza and eats at the cafe — it is a SaaS.
Now let us return to cloud technologies. IaaS – it's a structure of the servers, network resources and data storages. A provider of IaaS gives you access to previously enumerated goods and promises to give you with some technical support.
With PaaS you buy ready-made infrastructure where you can store and set up your products. Some providers also offer additional features like power resources management, DNS, etc.
SaaS — is a fully-fledged application for any user. All the technical stuff is made available by the provider. You just use the offered services as you wish.
The main question for now — "How do I pull my app into the cloud".
The first step — system audit. At this stage you have to know what parts of your infrastructure you will transfer. What should you bring to the new platform and what can be dropped.
If you decide to go the "as it is" way, it might be enough to create a snapshot of the server, convert it into an extension compatible with virtual machines and send it to the cloud.
If you decide to go with rebuilding, you might want to analyze what parts of the app should be remade. Such questions usually occur to developers at the first stage of the app audition. But you're advised to learn more about the cloud services your potential hosting can provide. It might be better to use them instead of trying to move your old stuff into the new system.
The second important thing is the amount of data that needs to be transferred. The more the data the harder and longer the process of transferring.
There are four problems that might pop up during the transfer:
Technological differences between your current platform and the one you want to bring data to (mostly it relates to companies with old technological stacks).
Dependencies between applications that were not resolved during infrastructure auditioning and came to light after deployment into the cloud.
Issues connected with the process of dividing monolith apps into microservices.
Vendor lock.
If you want to make transferring as smooth as possible, you have to follow a set of rules. First of all, create infrastructure in the cloud, bring data there and test it. Secondly, bring actual data and apps to these tested clouds.
Now you know what the process of migration to the cloud entails, what types of migration exist and how everything works, in general.
Migration is not a simple process; therefore, it is important that it is managed by professionals. For example, if you migrate to Hostman, our specialists will walk you through all the steps and make the data transition not just successful but extremely easy and quick.