scrapy crawler caught exception reading instance data

I am new to python and want to use scrapy to build a web crawler. I go through the tutorial in Spider code likes following:

from scrapy.spider         import BaseSpider
from scrapy.selector         import HtmlXPathSelector
from nettuts.items        import NettutsItem
from scrapy.http        import Request

class MySpider(BaseSpider):
     name         = "nettuts"
     allowed_domains    = [""]
     start_urls    = [""]

def parse(self, response):
    hxs     = HtmlXPathSelector(response)
    titles     ='//h1[@class="post_title"]/a/text()').extract()
    for title in titles:
        item = NettutsItem()
        item["title"] = title
        yield item

When launch the spider with command line: scrapy crawl nettus, it has following error:

[boto] DEBUG: Retrieving credentials from metadata server.
2015-07-05 18:27:17 [boto] ERROR: Caught exception reading instance data

Traceback (most recent call last):
  File "/anaconda/lib/python2.7/site-packages/boto/", line 210, in retry_url
    r =, timeout=timeout)

 File "/anaconda/lib/python2.7/", line 431, in open
response = self._open(req, data)

 File "/anaconda/lib/python2.7/", line 449, in _open
'_open', req)

 File "/anaconda/lib/python2.7/", line 409, in _call_chain
result = func(*args)

 File "/anaconda/lib/python2.7/", line 1227, in http_open
return self.do_open(httplib.HTTPConnection, req)

File "/anaconda/lib/python2.7/", line 1197, in do_open
raise URLError(err)

URLError: <urlopen error [Errno 65] No route to host>
2015-07-05 18:27:17 [boto] ERROR: Unable to read instance data, giving up

really do not know what's wrong. Hope somebody could help


in the file: add following code settings:


The important information is:

URLError: <urlopen error [Errno 65] No route to host>

That is trying to tell you that your computer doesn't know how to communicate with the site you're trying to scrape. Are you able to access the site normally (i.e. in a web-browser) from the machine you're trying to run this python on?

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