How do IaaS platforms handle workload migrations?

IaaS platforms handle workload migrations by providing tools and services that automate the transfer of applications, data, and virtual machines (VMs) between environments, such as on-premises systems to the cloud or between cloud regions. These platforms typically use a combination of snapshots, replication, and orchestration to minimize downtime and ensure consistency. For example, live migration allows VMs to move while running, maintaining active connections, while offline migration involves shutting down workloads before transferring them. IaaS providers abstract the complexity of underlying infrastructure, enabling developers to define migration parameters through APIs or graphical interfaces, which handle resource allocation, network configuration, and security policies automatically.

Specific tools like AWS Server Migration Service (SMS), Azure Migrate, and Google Cloud’s Migrate for Compute Engine illustrate how this works. AWS SMS uses incremental replication to copy VM disk data from on-premises servers to the cloud, reducing transfer time by only sending changed blocks after an initial full copy. Azure Migrate performs dependency mapping to identify interconnected workloads, ensuring all components move together without breaking functionality. Google Cloud’s tool supports cross-platform migrations (e.g., VMware to Google Cloud) by converting VM formats and adjusting storage configurations. These services often include validation checks, such as testing network connectivity or verifying storage compatibility, to prevent post-migration issues. Developers can script migrations using infrastructure-as-code tools like Terraform or CloudFormation, enabling repeatable, version-controlled processes.

Key considerations during migration include planning for dependencies, security, and performance. For instance, a database hosted on an IaaS platform might require adjusting firewall rules or IAM policies in the target environment to maintain access controls. Network latency between regions can impact real-time applications, so some teams use DNS routing policies or load balancers to redirect traffic gradually. Post-migration, monitoring tools like CloudWatch or Azure Monitor help track resource utilization and identify bottlenecks. Hybrid scenarios—where part of a system remains on-premises—may require VPNs or dedicated interconnects to ensure seamless communication. By combining automated tooling with careful planning, developers can execute migrations efficiently while minimizing disruption to live services.