ansible/ansible — pull request #9304 by ShawnMilo (2014-10-10 05:11:41+00:00)
Title: Give useful errors when rsync or ssh are not installed on the system.

I wasted way too much time today trying to figure out "file not found" errors. Especially with synchronize, since there is no traceback provided.

The problem was discovered running Ansible from within Docker. Docker images tend to be fairly stripped down, and their use is increasing. Ansible also seems to be the preferred configuration tool to be paired with Docker.