SSL letsencrypt 自动安装总是超时

按照这个执行  https://oneinstack.com/question/5673/  仍无法自动部署  letsencrypt  SSL证书。
总是提示，超时  An unexpected error occurred:
ReadTimeout: HTTPSConnectionPool(host='acme-v01.api.letsencrypt.org', port=443): Read timed out. (read timeout=45)
 
错误log
2017-05-19 15:20:00,066EBUG:certbot.log:Root logging level set at 30
2017-05-19 15:20:00,067:INFO:certbot.log:Saving debug log to /var/log/letsencryp t/letsencrypt.log
2017-05-19 15:20:00,068EBUG:certbot.plugins.selection:Requested authenticator webroot and installer None
2017-05-19 15:20:00,072EBUG:certbot.plugins.selection:Single candidate plugin: * webroot
Description: Place files in webroot directory
Interfaces: IAuthenticator, IPlugin
Entry point: webroot = certbot.plugins.webroot:Authenticator
Initialized: <certbot.plugins.webroot.Authenticator object at 0x7f79869a2c90>
Prep: True
2017-05-19 15:20:00,072EBUG:certbot.plugins.selection:Selected authenticator < certbot.plugins.webroot.Authenticator object at 0x7f79869a2c90> and installer No ne
2017-05-19 15:20:00,179EBUG:acme.client:Sending GET request to https://acme-v0 1.api.letsencrypt.org/directory.
2017-05-19 15:20:00,181EBUG:requests.packages.urllib3.connectionpool:Starting new HTTPS connection (1): acme-v01.api.letsencrypt.org
2017-05-19 15:20:45,869EBUG:certbot.log:Exiting abnormally:
Traceback (most recent call last):
File "/usr/local/python/bin/certbot", line 11, in <module>
sys.exit(main())
File "/usr/local/python/lib/python2.7/site-packages/certbot/main.py", line 742 , in main
return config.func(config, plugins)
File "/usr/local/python/lib/python2.7/site-packages/certbot/main.py", line 666 , in certonly
le_client = _init_le_client(config, auth, installer)
File "/usr/local/python/lib/python2.7/site-packages/certbot/main.py", line 382 , in _init_le_client
acc, acme = _determine_account(config)
File "/usr/local/python/lib/python2.7/site-packages/certbot/main.py", line 367 , in _determine_account
config, account_storage, tos_cb=_tos_cb)
File "/usr/local/python/lib/python2.7/site-packages/certbot/client.py", line 1 58, in register
acme = acme_from_config_key(config, key)
File "/usr/local/python/lib/python2.7/site-packages/certbot/client.py", line 4 4, in acme_from_config_key
return acme_client.Client(config.server, key=key, net=net)
File "/usr/local/python/lib/python2.7/site-packages/acme/client.py", line 71, in __init__
self.net.get(directory).json())
File "/usr/local/python/lib/python2.7/site-packages/acme/client.py", line 646, in get
self._send_request('GET', url, **kwargs), content_type=content_type)
File "/usr/local/python/lib/python2.7/site-packages/acme/client.py", line 619, in _send_request
response = self.session.request(method, url, *args, **kwargs)
File "/usr/local/python/lib/python2.7/site-packages/requests/sessions.py", lin e 518, in request
resp = self.send(prep, **send_kwargs)
File "/usr/local/python/lib/python2.7/site-packages/requests/sessions.py", lin e 639, in send
r = adapter.send(request, **kwargs)
File "/usr/local/python/lib/python2.7/site-packages/requests/adapters.py", lin e 514, in send
raise ReadTimeout(e, request=request)
ReadTimeout: HTTPSConnectionPool(host='acme-v01.api.letsencrypt.org', port=443): Read timed out. (read timeout=45)