What are the differences between cloud and on-premises database migration?

Cloud database migration involves moving data, applications, and other elements from an on-premises data center to a cloud environment, such as a cloud service provider. On the other hand, on-premises database migration refers to the process of transferring data and applications from one on-site server or data center to another on-premises location. The key distinction lies in the destination environment: cloud-based or on-premises. Cloud migration often offers scalability, flexibility, and potential cost savings, while on-premises solutions provide more control over hardware and security but may lack the same scalability.

Cloud database migration involves moving data to a cloud-based environment, offering scalability and accessibility benefits. On-premises migration, however, transfers data to a local server, providing control but limiting scalability. Cloud migration often requires a shift to a subscription-based model, while on-premises entails upfront hardware and software investments. Cloud databases offer easier updates and maintenance, whereas on-premises requires manual management. The cloud provides flexibility, while on-premises demands careful capacity planning. Ultimately, the choice depends on specific business needs, scalability requirements, and cost considerations.

Migration to Cloud based architectures can be a huge net add return on investment, so long as you consider the full architecture. Who is consuming? What does it talk to? Are there regulatory concerns? The benefits of a cloud based Database platform can be quickly washed away by distancing itself from its neighboring consumers. Plan to move the full environment, app servers and database servers, together.

Start with the database migration analysis tools provided by the cloud vendors. This will help you in identifying comparability issues that can arise in the migration process. Use this data to define your migration plan.

Cloud migration can also be the process of shifting you current on prem server requirement to a Hosted virtual private cloud of exactly the same servers in, for example, a VMware environment. You can either rebuild your business functions as you infer using alternate platforms with the Hyperscalers such as the 3 you mention on a metered charging model that often works out expensive. or you can use a lift and shift approach to just host your current server estate into the cloud typically with a fixed monthly fee. Better than that you can do it along side a DRaaS approach where physical servers are mirrored in cloud whilst you decide if this is how you want to improve your business.

Database migration It's not just about cloud or on-premise migration. Database migration may be required if you are planning to change or upgrade your application with new technology and tools. These days people use no-sql database and also talk about server less computing when we move to cloud. So database migration depends on situation and requirements of the organisation.

Migration strategy for on premise vary for different platforms. For IaaS, we might go for one to one approach as we might not have critical dependencies on cloud components. For PaaS, we need to be aware on what dependent components and services we need to build on premises for providing same level of functionalities. Security and scalability related components needs considerable efforts to build on on-premises.

And plenty of major data bases have this migration capability built in if you are just upgrading versions. Look to use the built in migration functions.

In my experience fisrt thing to do is based on the database engine involved think on the best strategy for a migration plan, besides digging around on migration needs, work on the infrastructure that will store the databases, making sure it is on the most stable version of firmware of each component, that is monitored accordingly, the team is empowered in its management, resources on it exceeds actual needs (extra careful to check on available resources instead of raw ones) - for hardware performance and scalability if It is reaching 65% of its available resorces, for me it is a warning flag to increase resources or find another plataform.

There are benefits to moving within on premise locales, to include refreshed hardware and higher availability of resources. Be sure to plan not only the capacity target locale, but also the labor and testing patterns. Lastly, moving isn't instantaneous, and the size of the environment will add time to movement. Consider this in your project planned outage window, and add a risk contingency in case your network takes longer to transit than expected (I recommend 15% time to the data replication window).

Choosing between cloud, on-premises, or a hybrid solution involves critical considerations. Costs must be weighed against scalability needs. Cloud offers flexibility and a pay-as-you-go model, but on-premises provides direct control. Security and data control are crucial, with on-premises allowing more direct oversight. Performance requirements, reliability, and uptime should align with business needs. Flexibility and agility are crucial for adapting to growing requirements. Integration with existing systems, data transfer considerations also play key roles. Remember that cloud solutions may require a different skill set currently not available in your organization.

For comparison in the context of cost, it's important to take into account the opportunity for savings derived from e.g. Committed Use, Reserved Instances, and/or Reserved Capacity ...depending the Cloud Provider(s) you are considering.

Certainly cost is a key migration consideration and one area often overlooked is ingress and egress costs - hyper scalars will often charge you for transferring data as well as the hosting its self. You also have to wonder if these article form enough information to allow you to complete your tasks as often the sanguine flow of words looks like a AI generated answer with us humans correcting the mistakes for free.

I agree, decisions must be made based on business needs, what can you afford now and eventually (cloud works on a pay as you go basis similar to a software suscription licensing - you don't own the infrastructure and payments will vary after negotiated term ends, on another hand on-premise infrastructure is yours but sooner or later will be obsolete and while we are getting there annual maintenance fees are required, besides in case we don't make an investment making sure we can face actual loads and new requirements, it will turn into a nightmare). I think that while comparing we must think in a 5 year basis, being able to discriminate in a neutral way pros and cons of cloud vs on-premises.

Once we have identified all the requirements then we can define different data migration strategies for different use cases. For example replica or mirror can be configured on on premises data centers for databases that supports replication or mirroring technologies. This will not only reduce downtime but also help in failing back in case of any issues in the migration process.

This generic best practice description seems very light on testing performance after what is probably going to be one of your biggest programmes in a year.

In my experience data and database engine knowledge is key (for example: it is not the same working with MS SQL or PostgreSQL, having domain knowlegde of data governance regarding databases to be migrated or don't have even a clue about it). Listing who/which/what/when/how databases are accessed and modified is a critical aspect so we can make sure proper arrangements are done to ensure migration will be transparent for normal operations. Optimizing and even securing the way data is accessed is something to consider as part of the migration plan, we must have as a goal to deliver an improved version of databases connections within our migration project.

don't trust the sales team. I migrated to the most expensive database solution in a major cloud provider. It was promoted as the fastest option and then we realized it wasn't better than the cheap one. Also consider that you get extra promtions on the first year that will not show the real cost later.

Some of the most common mistakes when migrating to cloud: 1. Migrating without proper planning: Companies need to evaluate the best providers for them and the pros and cons of each of them and if they even need migration in the first place. 2. Completely removing physical database: It is better to have a backup first before completing the migration. The physical databases can be slowly transitioned as the migration is fully completed. 3. Working in silos: Migrations should not happen in silos, vendors, clients and all teams should be updated regularly in case something goes wrong.

Cost control should never be forgotten. On-prem can lack flexibily but cloud can easily expand capacity and cost. The key technical question is whether there are any on-prem applications accessing the database and does moving the database to the cloud affect the response times that the users experience.