title: Various Curl/SSL-errors on Azure hosted images
body: <p>The company where I'm working is currently moving all their sites from a self-managed Linux VPS to cloud based Microsoft Azure hosting.
  In this process, the major downside I experience is an unexplainable Curl error, which seem to occur only when Microsofts crawlers request an image.</p>
  
  <p>The setup is like this: the images (all the images used on our website, like product images etc) are hosted on an Azure Blob Storage account, but for various reasons we do not use the direct link to these blobs, but send an URL to the user like domain.com/images/123.jpg, which in turn gets the image from the Azure Storage account and displays it to the user.
  This might not be the most efficient solutions, but it's how the company owners wants it, and it works for all the users. Changing this behaviour is not really a possibility.</p>
  
  <p>The only problem is, that when an image is requested by a bot/crawler from Microsoft, it all goes wrong.
  We got a few different errors, like <em>SSL connection timeout</em>, <em>name lookup timed out</em> and <em>connect() timed out!</em>.</p>
  
  <p>First I thought this can be caused by Azure blocking other Microsoft IP's, but since the request is proxied by another server, this can't be the cause.</p>
  
  <p>Azure's documentation on this is totally non-existent, and Google only gives me some generic, non-Azure related solutions, which didn't help me.</p>
  
  <p>The site is build in PHP 7.</p>