请各位帮我看看安装devstack的蛋疼问题，40分奉上！

基于ubuntu14.04.4 LTS 版本在VMware Workstation 12 Pro安装，主要参考陈沙克老师所写的安装方法步骤http://www.chenshake.com/install-ubuntu-14-04-devstack/ ，但安装了十几遍，还是安装不下去，问题如下：
1、按照最小化方式安装了ubuntu14.04.4 LTS查看python版本，结果如下，确定当前本机python版本是2.7.
stack@ubuntuss:/home/devstack$ /usr/bin/python
Python 2.7.6 (default, Jun 22 2015, 17:58:13)
[GCC 4.8.2] on linux2
Type “help”, “copyright”, “credits” or “license” for more information.
可是安装过程中还是会经常显示这句异常
Ignoring dnspython3: markers “python_version==’3.4′” don’t match your environment

2、现在每次安装时 最终都卡在这一步进行不下去了，我确定不是网速问题，我这边下载速度2兆左右，最终显示错误如下：
2016-04-25 00:51:56.861 | Collecting pysaml2===4.0.2 (from -c /opt/stack/requirements/upper-constraints.txt (line 272))
2016-04-25 00:51:57.396 | Downloading pysaml2-4.0.2.tar.gz (13.7MB)
2016-04-25 00:55:54.922 | Exception:
2016-04-25 00:55:54.922 | Traceback (most recent call last):
2016-04-25 00:55:54.923 | File “/usr/local/lib/python2.7/dist-packages/pip/basecommand.py”, line 209, in main
2016-04-25 00:55:54.923 | status = self.run(options, args)
2016-04-25 00:55:54.923 | File “/usr/local/lib/python2.7/dist-packages/pip/commands/install.py”, line 310, in run
2016-04-25 00:55:54.923 | wb.build(autobuilding=True)
2016-04-25 00:55:54.923 | File “/usr/local/lib/python2.7/dist-packages/pip/wheel.py”, line 748, in build
2016-04-25 00:55:54.923 | self.requirement_set.prepare_files(self.finder)
2016-04-25 00:55:54.923 | File “/usr/local/lib/python2.7/dist-packages/pip/req/req_set.py”, line 360, in prepare_files
2016-04-25 00:55:54.923 | ignore_dependencies=self.ignore_dependencies))
2016-04-25 00:55:54.923 | File “/usr/local/lib/python2.7/dist-packages/pip/req/req_set.py”, line 577, in _prepare_file
2016-04-25 00:55:54.923 | session=self.session, hashes=hashes)
2016-04-25 00:55:54.923 | File “/usr/local/lib/python2.7/dist-packages/pip/download.py”, line 810, in unpack_url
2016-04-25 00:55:54.924 | hashes=hashes
2016-04-25 00:55:54.924 | File “/usr/local/lib/python2.7/dist-packages/pip/download.py”, line 649, in unpack_http_url
2016-04-25 00:55:54.924 | hashes)
2016-04-25 00:55:54.924 | File “/usr/local/lib/python2.7/dist-packages/pip/download.py”, line 871, in _download_http_url
2016-04-25 00:55:54.924 | _download_url(resp, link, content_file, hashes)
2016-04-25 00:55:54.925 | File “/usr/local/lib/python2.7/dist-packages/pip/download.py”, line 595, in _download_url
2016-04-25 00:55:54.925 | hashes.check_against_chunks(downloaded_chunks)
2016-04-25 00:55:54.925 | File “/usr/local/lib/python2.7/dist-packages/pip/utils/hashes.py”, line 46, in check_against_chunks
2016-04-25 00:55:54.926 | for chunk in chunks:
2016-04-25 00:55:54.926 | File “/usr/local/lib/python2.7/dist-packages/pip/download.py”, line 563, in written_chunks
2016-04-25 00:55:54.926 | for chunk in chunks:
2016-04-25 00:55:54.927 | File “/usr/local/lib/python2.7/dist-packages/pip/utils/ui.py”, line 139, in iter
2016-04-25 00:55:54.927 | for x in it:
2016-04-25 00:55:54.927 | File “/usr/local/lib/python2.7/dist-packages/pip/download.py”, line 552, in resp_read
2016-04-25 00:55:54.927 | decode_content=False):
2016-04-25 00:55:54.928 | File “/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/response.py”, line 344, in stream
2016-04-25 00:55:54.928 | data = self.read(amt=amt, decode_content=decode_content)
2016-04-25 00:55:54.928 | File “/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/response.py”, line 311, in read
2016-04-25 00:55:54.928 | flush_decoder = True
2016-04-25 00:55:54.928 | File “/usr/lib/python2.7/contextlib.py”, line 35, in __exit__
2016-04-25 00:55:54.929 | self.gen.throw(type, value, traceback)
2016-04-25 00:55:54.929 | File “/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/packages/urllib3/response.py”, line 240, in _error_catcher
2016-04-25 00:55:54.929 | raise ReadTimeoutError(self._pool, None, ‘Read timed out.’)
2016-04-25 00:55:54.930 | ReadTimeoutError: HTTPSConnectionPool(host=’pypi.python.org’, port=443): Read timed out.
2016-04-25 00:55:55.181 | +inc/python:pip_install:1 exit_trap
2016-04-25 00:55:55.189 | +./stack.sh:exit_trap:474 local r=2
2016-04-25 00:55:55.197 | ++./stack.sh:exit_trap:475 jobs -p
2016-04-25 00:55:55.204 | +./stack.sh:exit_trap:475 jobs=
2016-04-25 00:55:55.212 | +./stack.sh:exit_trap:478 [[ -n ” ]]
2016-04-25 00:55:55.218 | +./stack.sh:exit_trap:484 kill_spinner
2016-04-25 00:55:55.229 | +./stack.sh:kill_spinner:370 ‘[‘ ‘!’ -z ” ‘]’
2016-04-25 00:55:55.236 | +./stack.sh:exit_trap:486 [[ 2 -ne 0 ]]
2016-04-25 00:55:55.242 | +./stack.sh:exit_trap:487 echo ‘Error on exit’
2016-04-25 00:55:55.242 | Error on exit
2016-04-25 00:55:55.250 | +./stack.sh:exit_trap:488 generate-subunit 1461545128 627 fail
2016-04-25 00:55:55.544 | +./stack.sh:exit_trap:489 [[ -z /opt/stack/logs ]]
2016-04-25 00:55:55.550 | +./stack.sh:exit_trap:492 /home/devstack/tools/worlddump.py -d /opt/stack/logs
2016-04-25 00:55:55.701 | 2016-04-25T00:55:55Z|00001|reconnect|WARN|unix:/var/run/openvswitch/db.sock: connection attempt failed (Permission denied)
2016-04-25 00:55:55.701 | ovs-vsctl: unix:/var/run/openvswitch/db.sock: database connection failed (Permission denied)
2016-04-25 00:55:56.033 | +./stack.sh:exit_trap:498 exit 2

3、按照网上有些人说更换了豆瓣源，直接提示这个错误Could not fetch URL http://pypi.douban.com/simple/pip/ 导致连接不上，我的pip.conf所写内容如下：
[global]
index-url = http://pypi.douban.com/simple/

以上问题已折磨小弟一周了，烦请各位予以协助指教，谢谢！