Caching and Upstream Proxying for Debian Packages

Sept 4 2020/Software Package Formats/3 min read
We are happy to announce that Cloudmith now supports proxying and caching of upstream Debian repositories. Simplify your configuration and gain more control and visibility.

At Cloudsmith, we want to be your “one central source of truth” for your dependencies and package management needs. And in keeping with this ideal, we are extremely pleased to announce that we have added fully configurable transparent Proxying and Caching support for Debian packages.

Why does this matter?

Well, in short, it means that you can now use your private Cloudsmith repository for all of your Debian package needs – whether that is your own private packages or packages that you need from public upstream sources.  Your private Cloudsmith repository is all that you need to handle both.

If you request a package from your Cloudsmith repository, and that package isn’t present in the repo, then Cloudsmith will automatically check any upstream repos that you have configured and will then fetch (and optionally cache the package for future requests) from the upstream.

This brings you several important benefits:

  • Easier setup. Your Cloudsmith repository is the only repository you need to configure on your clients. No more need to configure multiple repos, and handle multiple authentication credentials etc. Configure the upstreams once in Cloudsmith, and that’s it done.
  • Isolation. If you have cached packages and dependencies that you require in your Cloudsmith repository, then if the upstream repo goes down, is otherwise unavailable, or if the packages are removed then you can still access your cached versions. No more breaking of build or deployment process due to an unreliable upstream.
  • Visibility. You can view details on what specific packages were requested from the upstreams. Gain insights into what you have, and what’s missing – or who and what else you are currently relying on.
  • Performance. Cloudsmith repositories are backed by a performant, global CDN. This means that your own packages and those cached from an upstream are delivered with the same low latencies and speeds. Going further than this, with edge nodes in almost all geographic regions, your users will experience this performance wherever they are located. Distributed teams all benefit equally.
  • Security and Control. All of your packages and dependencies in one place means it’s easier for you to implement the controls and security policies that you need. Multiple sources mean multiple management tasks. Keep everything in one place and keep a tighter hold on what you have.

Sounds Great!. How do we set this up?.

Well, it’s easy. In your Cloudsmith repository, you’ll see a menu item called “Upstream Proxying”. This is where we will configure our upstreams. Simply click the “Create Upstreams” button and select “Debian” to create a new Debian upstream:

You are then presented with the “Edit Debian Upstream” form.  This is where we enter the details of the Debian upstream we wish to use.

We add a Name for the upstream, it’s URL and a priority weighting- in cases of multiple upstreams this will determine the order in which they are checked for a package.

We can then choose to fetch and cache any requested package (instead of just fetching them), and to verify the SSL certificates provided by the upstream. In addition, we can choose to enable this upstream for source packages too.

Next, we select the distributions and architectures that we wish to use this upstream for, and finally, we can add optional authentication headers (for private repositories that require authentication) and also optional arbitrary headers, if you wish to send something custom along with your request.

And that’s it, we have now added a new Debian upstream to our Cloudsmith repository.

Behind the scenes, Cloudsmith will now start to index the packages available in the upstream repository.  The upstream will be ready for use as soon as the indexing is complete.

So now, for the next request for a package that isn’t present in this repository, Cloudsmith will check the upstream and fetch it if it is available there and also cache it in the Cloudsmith repo (if you enabled caching) for future requests. It’s that simple.


Debian upstream proxying and caching support is just another step on our path to providing you with the centralized controls, security, management and visibility that you need to enable a modern, high-velocity and DevOps-first workflow for your package management needs. It means fewer things to worry about, less exposure to change and most importantly....

Well, what's most important to you? Let us know!

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