I have just switched a Jenkins project from Svn to git (hosted on GitHub). When I wanted to build the project I experienced the following error: Host key verification failed.

The first issue was, that Jenkins didn’t run with the normal user, but it’s own Jenkins user. So I switched to this user

su jenkins

and created an own private/public key using

ssh-keygen

After this I tried to ssh into git

ssh git@github.com

and got a welcome message:

You’ve successfully authenticated, but GitHub does not provide shell access.

After this I tried to clone the repository to the Jenkins machine and got

hudson.plugins.git.GitException: Could not apply tag …

This problem could be fixed by adding git name and email via

git config --global user.email "email@yourdomain.com"
git config --global user.name "Jenkins"