Is there a migration tool from CVS to Git?

The only tool that has incremental import seems to be git-cvsimport. If you want to convert (migrate) from CVS to Git, the best solution for now seems to be mentioned above cvs2git mode of cvs2svn.

See also Interfaces Frontends And Tools page on Git wiki, section about interaction with other revision control systems.

cvs2git

In addition to provided answers, here's a guide on how to convert cvs to git using cvs2git tool. Here, modulename is a name of CVS directory you want to import.

Prerequisites

cvs2svn package (which includes cvs2git command) should be already installed.

Update: steps 1 and 2 are not fully correct - before attempting, read the comment below by mhagger, the maintainer of cvs2git

1. checkout modulename

   cvs -d URL co -P modulename
   

2. create an empty CVSROOT needed by cvs2git

   mkdir modulename/CVSROOT
   

3. download an example of cvs2git.options at http://cvs2svn.tigris.org/svn/cvs2svn/trunk/cvs2git-example.options (user "guest" with no password)

4. edit cvs2git.options file. Replace r'test-data/main-cvsrepos' with 'modulename'. Edit authors transforms.

   # edit this
   run_options.set_project(  r'modulename',
   
   # and this
   author_transforms={
       'jrandom' : ('J. Random', '[email protected]'),
       'mhagger' : 'Michael Haggerty <[email protected]>',
   

5. run cvs2git to create git temp files

   cvs2git  --options=cvs2git.options --fallback-encoding utf-8
   

6. create git repository

   mkdir gitrepo && cd gitrepo && git init .
   

7. import from git temp files created by cvs2git

   cat ../cvs2git-tmp/git-{blob,dump}.dat | git fast-import
   

8. checkout working copy

   git reset --hard