Hi,
I upgraded to dropwizard 2 a few months ago.
Are you already on jdbi3? If not, this alone will be a lot of work (Although according to the guide you can still try and work with Jdbi 2, but I don't think it's recommended)
Is your code tested well? Strong integration tests between microservices? And for external clients?
You're going to bump a major version of Jackson as well.
Are you running Java? (I did it with Kotlin and I had a few issues with Jackson and kotlin data classes).
I suggest first trying to bump the dropwizard version in your pom.xml (assuming you're using maven), and also add a dependency management of type "pom" on the dropwizard-dependencies artifact.
This is to force all other libraries versions to be compatible with the dropwizard version. In short, try making sure you don't have versions converging as much as possible.
Then try to make your code compile (if the migration guide does not help you, share here your difficulties).
Then, try to make it run (same).
Then test it.
Good Luck!