Migrating from ClearCase

ClearCase is a set of tools developed by IBM which also include a centralized version control system similar to Git.

A good read of ClearCase’s basic concepts is can be found in this StackOverflow post.

The following table illustrates the main differences between ClearCase and Git:

AspectClearCaseGit
Repository modelClient-serverDistributed
Revision IDsBranch + numberGlobal alphanumeric ID
Scope of ChangeFileDirectory tree snapshot
Concurrency modelMergeMerge
Storage MethodDeltasFull content
ClientCLI, Eclipse, CC ClientCLI, Eclipse, Git client/GUIs
ServerUNIX, Windows legacy systemsUNIX, macOS
LicenseProprietaryGPL

Taken from the slides ClearCase and the journey to Git provided by collab.net

Why migrate

ClearCase can be difficult to manage both from a user and an admin perspective. Migrating to Git/GitLab there is:

  • No licensing costs, Git is GPL while ClearCase is proprietary.
  • Shorter learning curve, Git has a big community and a vast number of tutorials to get you started.
  • Integration with modern tools, migrating to Git and GitLab you can have an open source end-to-end software development platform with built-in version control, issue tracking, code review, CI/CD, and more.

How to migrate

While there doesn’t exist a tool to fully migrate from ClearCase to Git, here are some useful links to get you started: