ansible执行命令出错
报错：ERROR! Unexpected Exception, this is probably a bug: (cryptography 0.8.2 (/usr/lib64/python2.7/site-packages), Requirement.parse('cryptography>=1.1'))
解决：
删除列出软件包，并重装即可
rpm -qa |grep python-crypto
yum -y remove python-cryptography
yum -y install ansible
ansible all -m ping -k
