When I’m installing DevStack, it performs the following:

++ FORCE_FIREWALLD=False

++ [[ rhel7 =~ (f20) ]]

++ uninstall_package python-virtualenv

++ is_ubuntu

++ [[ -z rpm ]]

++ '[' rpm = deb ']'

++ is_fedora

++ [[ -z CentOS ]]

++ '[' CentOS = Fedora ']'

++ '[' CentOS = 'Red Hat' ']'

++ '[' CentOS = CentOS ']'

++ sudo yum remove -y python-virtualenv

Loaded plugins: fastestmirror, rhnplugin

This system is receiving updates from RHN Classic or Red Hat Satellite.

Resolving Dependencies

--> Running transaction check

---> Package python-virtualenv.noarch 0:1.10.1-2.el7 will be erased

--> Finished Dependency Resolution

Dependencies Resolved

================================================================================

Package                  Arch          Version              Repository    Size

================================================================================

Removing:

python-virtualenv        noarch        1.10.1-2.el7         @base        1.6 M

Transaction Summary

================================================================================

Remove  1 Package

Installed size: 1.6 M

Downloading packages:

Running transaction check

Running transaction test

Transaction test succeeded

Running transaction

  Erasing    : python-virtualenv-1.10.1-2.el7.noarch                        1/1

  Verifying  : python-virtualenv-1.10.1-2.el7.noarch                        1/1

Removed:

  python-virtualenv.noarch 0:1.10.1-2.el7                                      

…

++ pip_install virtualenv

+++ set +o

+++ grep xtrace

++ local 'xtrace=set -o xtrace'

++ set +o xtrace

++ sudo -H http_proxy= https_proxy= no_proxy= /bin/pip install virtualenv

Requirement already satisfied (use --upgrade to upgrade): virtualenv in /usr/lib/python2.7/site-packages

…

Only to complain later:

+++ mktemp -d tmp-venv-XXXX

++ TMP_VENV_PATH=tmp-venv-uUwo

++ virtualenv tmp-venv-uUwo

/opt/stack/tools/build_wheels.sh: line 57: virtualenv: command not found

+++ err_trap

WHAAAAT?

Y.