Almost every organization has transitioned some operational systems to the cloud. DevOps professionals are an essential part of migration projects, facilitating the migration itself, and making sure applications work as expected and provide satisfactory performance after the migration.

To make your next cloud migration a success, you must get monitoring right. Applications must be monitored at every stage of the migration—when the application is still running on-premises, during migration and once the new workload is running in the cloud.

In this article, we will explain key metrics to track during your migration, monitoring considerations at every stage of the migration cycle, and free tools offered by the major cloud providers that can help you monitor your migration.

What to Monitor During a Cloud Migration

There are many components involved in a cloud migration process. There are several approaches to cloud migration—each migration is unique, and might necessitate setting up different metrics. However, there are several aspects that can be considered mandatory when monitoring your cloud migration process:

Tracking application traffic. Tracking application traffic can help you validate that application configurations are properly defined and validate the availability of the entire application. You should ensure that all requests arrive to the new server, and keep an eye on the error rate. Additionally, watch for response times to ensure your application is not exceeding the planned thresholds.
Tracking your costs. Tracking costs can help you ensure that you are not incurring unexpected losses. The majority of organizations migrate to the cloud to reduce their costs. However, incorrect implementation of cloud resources may lead to losses. You can gain visibility into your costs by leveraging first-party cloud tools, like AWS Billing, which natively integrate into the pipeline, monitor costs, and show visualized data in customized dashboards. You can also use these tools to set up alerts.
Monitoring application security. Application security monitoring can help you identify security vulnerabilities and incidents during and after the migration process. You should monitor infrastructure configurations, such as internal traffic, host open ports and instance processes that are actively accessing different services. Additionally, keep watch for API hits per second, which might indicate a distributed denial of service (DDoS) attack.

Monitoring Aspects of the Migration Life Cycle

Cloud service providers typically identify three main phases of the migration process, which are referred to as the plan, migrate and run phases.

Plan Phase

The plan phase helps you assess the performance levels of your applications before migrating. The goal is to achieve an in-depth understanding of how workloads are functioning pre-migration, as well as the current state of user experience. This data can then be used to establish performance benchmarks and baselines.

Performance baselines, like error rates, page load times and slow transactions, can help you set up configuration alerts that keep track of outages across the cloud migration process. You can then quickly diagnose the situation and apply fixes that ensure application health during and after the migration.

Here are several questions that can help you during the plan phase:

What is the application baseline?
How will the migration process affect user experience?
What are the potential technical challenges expected during the migration process?
Can the corporate network support additional bandwidth needs?
What are the steps needed to start the migration process?

Migrate Phase

The migrate phase involves all processes required to securely move components from one location to another. During this process, you should continuously monitor performance to ensure user experience remains within the pre-established baseline. However, migrating to the cloud means you no longer have control over all configurations.

To ensure application performance and stability during the migration process, you need to identify potential roadblocks and issues, and continuously monitor and validate the process. You should test critical aspects like application response time and call counts, and troubleshoot issues quickly.

Run Phase

The run phase starts right after the migration process is complete. During the post-migration phase, you need to establish proactive monitoring processes. The goal is to ensure your application performs well in the cloud; using the expected resources and without incurring overhead.

When monitoring your application, keep track of service level agreements (SLAs) to ensure the cloud vendor meets the requirements agreed upon. You should also monitor for changes and review individual variables that might cause issues.

Additionally, you should make sure all connections between applications are maintained after the migration.

Free Cloud Migration Monitoring Tools

The three major cloud providers—Amazon, Microsoft Azure and Google Cloud—provide tools that help automate migration to their clouds, and also assist with the crucial aspects of monitoring. These tools are offered free, because it is in the best interest of the cloud providers to allow easy, frictionless migration.

The following table summarizes migration monitoring capabilities available from each cloud provider.

Cloud Provider Tool	What it Helps Monitor
AWS Migration Services Helps automate migration of applications that rely on databases.	Continually monitors source and target databases Able to restart failed migrations Oversees continuous data replication Integrates with first-party AWS monitoring tools
Azure Migration Tools Provides a migration hub that lets organizations manage large migration projects.	Tracks migration process and current status for server and database migrations Allows external tools to integrate and track migrations Reports on compliance aspects of migrations
Migrate for Google Compute Engine Formerly known as Velostrata, this tool automates migration of on-premises systems, with automated roll back in case of errors.	Validation of workloads for migration compatibility Ongoing oversight of streaming data transfers Ability to roll back migration to on-premises systems in case of error

Monitoring is critical for a successful cloud migration, and it’s important to use monitoring at every stage of a cloud migration:

During the plan phase, establish a baseline of application performance before it is migrated to the cloud.
During the migration phase, carefully monitor application behavior and troubleshoot issues.
During the run phase, validate that the application performs as expected and is meeting SLAs.

I hope this will be useful as you plan and execute your next cloud migration project.