Comment 4 for bug 1598324

Looks like issue is caused by sudo.

For example when I'm testing with openstack-ansible-os_nova and launching ./run-test.sh

Process hangs on task:
TASK: [lxc_hosts | Create base container]

$pstree -p | grep ansible returns be such string

       ├─sshd(1216)───sshd(1270)───bash(1271)───sudo(1289)───su(1290)───bash(1291)───bash(1381)───tox(1875)───ansible-playboo(2092)───sh(6684)───sh(6685+

$pstree -p 2092 returns me:
ansible-playboo(2092)───sh(6684)───sh(6685)───sudo(6687)───sh(6688)───python(6689)───lxc-create(6690)───lxc-download(6692)───gpg(6709)───gpgkeys_hkp(6710+

next attemp:
$pstree -p 2092
ansible-playboo(2092)───sh(6721)───sh(6722)───sudo(6724)───sh(6725)───python(6726)───lxc-create(6727)───lxc-download(6729)───gpg(6773)───gpgkeys_hkp(6774+

$ strings /proc/6725/environ | grep http
$ strings /proc/6724/environ | grep http
HTTPS_PROXY=http://xx.xx.x.xx:8123
https_proxy=http://xx.xx.xx.xx:8123
http_proxy=http://xx.xx.xx.xx:8123
HTTP_PROXY=http://xx.xx.xx.xx:8123

$ ps ax | grep 6724
 6724 pts/0 S+ 0:00 sudo -H -S -p [sudo via ansible, key=wjafxzugogwfwinqmrkobraxivvcftbi] password: -u root /bin/sh -c echo BECOME-SUCCESS-wjafxzugogwfwinqmrkobraxivvcftbi; LC_CTYPE=en_US.UTF-8 LANG=en_US.UTF-8 /usr/bin/python /root/.ansible/tmp/ansible-tmp-1468018262.67-201069123544133/lxc_container; rm -rf /root/.ansible/tmp/ansible-tmp-1468018262.67-201069123544133/ >/dev/null 2>&1

$ ps ax |grep 6726
 6726 pts/0 S+ 0:00 /usr/bin/python /root/.ansible/tmp/ansible-tmp-1468018262.67-201069123544133/lxc_container
 6795 pts/1 S+ 0:00 grep --color=auto 6726

It is well know and recommended behavior for sudo:
https://help.ubuntu.com/community/EnvironmentVariables

As local workaround for dev and testing environments I think this sudo configuration can be/should be changed by using conf setting like this:
 Defaults env_keep += "http_proxy no_proxy https_proxy NO_PROXY HTTPS_PROXY HTTP_PROXY"