A cloud migration has nine challenges that always come up, regardless of the team, the workload, or the cloud provider. The right answer for each challenge is not the same for every team. The right answer depends on the workload, the team, and the cloud.
Table of contents
- The nine challenges
- Data security and compliance
- Cost management
- The right provider
- Downtime planning
- Skills gap
- Application complexity
- Data migration
- Application compatibility
- The long tail
- FAQ
The nine challenges
The nine challenges that always come up:
- Data security and compliance.
- Cost management and budgeting.
- The right cloud provider.
- Downtime planning.
- Skills gap.
- Application complexity.
- Data migration.
- Application compatibility.
- The long tail.
Data security and compliance
The first challenge is data security and compliance. The team has to know what data is leaving the data center, where the data is going, who can read it, and how it is encrypted.
The right answer for most teams: classify the data before the migration, encrypt the data in transit and at rest, and verify the cloud provider’s compliance certifications.
Cost management
The second challenge is cost management. The team has to know what the cloud bill is going to be, who is paying, and how the cost is going to be allocated.
The right answer for most teams: model the cost before the migration, set up the cost report before the workload goes live, and assign a cost owner for every workload.
The right provider
The third challenge is picking the right cloud provider. The right answer for most teams is the provider the team is already on. The team that is all-in on AWS should stay on AWS. The team that is all-in on Azure should stay on Azure.
The trap: the team picks a different provider for the migration because the cost is lower. The team spends a year migrating, and the savings are wiped out by the migration cost. The right answer: stay on the provider the team is already on, unless there is a strong business reason to switch.
Downtime planning
The fourth challenge is downtime planning. The team has to know how much downtime the migration will cause, when the downtime will happen, and how to communicate it to the users.
The right answer for most teams: plan for zero downtime, accept some downtime, and communicate the downtime to the users in advance. The team that plans for zero downtime is the team that ends up with the most downtime.
Skills gap
The fifth challenge is the skills gap. The team has to know how to operate the cloud, how to deploy to the cloud, and how to debug the cloud. The team that does not have the skills is going to learn them during the migration, which is the most expensive time to learn.
The right answer for most teams: train the team before the migration, hire a senior cloud engineer, or partner with a cloud consultancy. The team that does the migration without the skills is the team that ends up with the most expensive migration.
Application complexity
The sixth challenge is application complexity. The team has to know which applications are easy to migrate, which are hard, and which are too complex to migrate.
The right answer for most teams: classify the applications before the migration, pick the strategy for each (rehost, replatform, repurchase, refactor, retire, retain), and migrate the easy ones first.
Data migration
The seventh challenge is data migration. The team has to know how to move the data, how long it will take, and how to verify the data is correct.
The right answer for most teams: use the cloud provider’s native data migration service (AWS DMS, Azure Database Migration Service, Google Cloud Database Migration Service), test the migration with a small dataset first, and verify the data with a checksum or a row count.
Application compatibility
The eighth challenge is application compatibility. The team has to know which applications will run on the cloud, which need changes, and which are too tightly coupled to the on-premises stack to migrate.
The right answer for most teams: test the application on the cloud before the migration, identify the changes that need to be made, and plan for the changes in the migration timeline.
The long tail
The ninth challenge is the long tail. The team has to know that the migration is not done when the workload is in the cloud. The long tail is the optimization, the cost tuning, the security review, the compliance audit, and the operational handoff that happens after the workload is live.
The right answer for most teams: plan for a 3-6 month long tail after the migration, with a dedicated team or a dedicated person to handle the optimization and the handoff.
FAQ
What are the most common cloud migration challenges?
The nine that always come up: data security, cost management, the right provider, downtime planning, skills gap, application complexity, data migration, application compatibility, and the long tail.
What is the most important cloud migration challenge?
The skills gap. The team that does not have the skills is going to learn them during the migration, which is the most expensive time to learn. The right answer is to train the team or hire before the migration.
What is the difference between rehost and replatform?
Rehost is moving the workload as-is. Replatform is moving the workload with minor changes. Replatform is the middle ground; it is the most common strategy.
How long does a cloud migration take?
The migration itself takes 3-12 months for most workloads. The long tail (optimization, cost tuning, security review) takes another 3-6 months. The team that plans for the long tail does the migration in 6-18 months.
How do I avoid the long tail?
Plan for it. Allocate 3-6 months after the migration for a dedicated team or a dedicated person to handle the optimization, the cost tuning, the security review, and the operational handoff.
If you are sizing a cloud migration project, the RunxBuild hosting calculator is the place to model the line items. The migration, the optimization, the long tail - each one is a separate number, and the team’s mental model for the project is the sum of those numbers. The RunxBuild dashboard is where the team sees the post-migration production in one place.