Cloud Files Enhances Scale And Security Of Our Content Delivery Network (CDN)

In an effort to continuously enhance the scale and security of our Cloud Files and CDN products, Cloud Files will be changing the format of our CDN URLs.

The good news is that ALL EXISTING CDN URLs WILL CONTINUE TO FUNCTION AS NORMAL even after we make this change.

Beginning in mid-August, the Cloud Files team will make a system change that is designed to allow the Cloud Files infrastructure to scale more efficiently, reduce the risk of CDN downtime and increase the protection of your CDN URLs from DDoS (distributed denial of service) attacks.

In order to do this, we have to change the format of our CDN URLs.

Today, if you add a file to your container (e.g. mydog.png) and CDN-enable it, that CDN URL would have a format that looks like this:

After we complete our change, your new CDN URL would have a format that looks like this:

Once we have made this change, both our control panels and our APIs will return the new form URLs.  While the URL you see will be different from your existing URL, existing URLs will always continue to work as normal. 

This change will take several weeks as we upgrade each of our datacenters, and should be implemented by the end of August for all customers.

If you have any questions about this change and how it will affect your content, please feel free to reach out to me directly,

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  1. Matt- These are definitely a bit longer. If they are too long for you to use, remember that your existing URLs will still work. You can also take advantage of CNAMEs if that’s helpful.

  2. @Mark- CNAMEs on SSL did not work with the prior CDN URLs either. This is a limitation to the way we allow customers do their CNAMEs, not the new form URLs. Great point, though. I should have mentioned that this change is not expected to help with SSL and CNAMEs.

  3. This will cause some people problems. I just tried to change my CNAME (even though it’s not needed, it seems better to use the new URLs than the old ones, just in case the old ones DO get dropped by rackspace at some point in the future).

    The result?

    “The domain name you entered is too long”

    This is obviously an issue with 1&1’s control panel, but I won’t be the only person who has domains registered with 1&1!

  4. @Seb- I just spoke with 1&1 as well. (I was hoping to convince them to do a one-off). If you’re open to it, we can talk about options for keeping your domain registered at 1&1 but manage it through Rackspace’s Cloud DNS product. It might not be the ideal solution, but with a few configuration changes, we could probably get you around this limit and back up and running with your CNAMEs. I am happy to personally facilitate those discussions if you’d like, just shoot me an email at

  5. Well, I can still use a cname to the “old” CDN url. Will they continue to work indefinitely, or do you anticipate them being dropped in a few months?

    I did some googling and came to the same conclusion that you did – that the only “solution” is to move my DNS elsewhere. Which tbh I’d be fine with, I’ve learnt a lot since first setting up with 1&1 many years ago before I knew of their reputation…

    Happy to leave it as it is for the time being though.

  6. @Seb- We don’t have any plans to discontinue those URLs at this point. In fact, we’re still supporting CDN URLs from many many years ago with “mosso” in them. If we do decide to discontinue these URLs at any point, we would ensure that we notified any customers still using them in plenty of time to adjust their setup.

    • Actually, turns out the answer is: by the same method as before. I didn’t look at the new url patterns closely enough…

  7. To clarify I think Megan means any new CDN containers will get the new-type URL. You can upload content to an existing container and it’ll work on both the new-form URL *and* the old URLs you had before.

  8. Megan,

    Can you clarify that the OLD url format will work on new files in existing containers? Or will new files in existing containers only work with the new URL format?

  9. @Michael Yes, sorry about the confusion. While Rackspace won’t return the old URL format for any object going forward, an object that exists in a container that was CDN enabled before this change can still use the old form of URLs. The user will just have to construct the URL themselves using the old container ID, rather than having it returned by Cloud Files.

    Again, sorry for the confusion, I hope this clears things up.

  10. @megan, could you elaborate on the specifics on what “infrastructure to scale more efficiently, reduce the risk of CDN downtime and increase the protection of your CDN URLs from DDoS” means? Are these primarily the result of new in-house Rackspace work or newer Akamai features? Just curious.


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