You have a few options for the types of tools you can use to migrate to the cloud.
Open Source: Open source solutions can be customized at just about every level, and they are often free or low-cost. The downside is that you will likely need experienced staff to make the customizations.
Batch Processing: Batch processing tools work well in environments where large amounts of data are moved or processed at regularly scheduled times (often nightly, when network and equipment use is low).
Cloud-based: Cloud-based migration tools typically offer the most seamless experience, tying together data and the cloud with connectors and tool sets designed for that specific task.