<p>I am trying to build and deploy microservices images to a single-node Kubernetes cluster running on my development machine using minikube. I am using the cloud-native microservices demo application Online Boutique by Google to understand the use of technologies like Kubernetes, Istio etc. </p>

<p>Link to github repo: <a href="https://github.com/GoogleCloudPlatform/microservices-demo" rel="noreferrer">microservices-demo</a></p>

<p>While following the installation process, and on running command <code>skaffold run</code> to build and deploy my application, I get some errors:</p>

<pre><code>Step 10/11 : RUN apt-get -qq update     &amp;&amp; apt-get install -y --no-install-recommends         curl
 ---&gt; Running in 43d61232617c
W: GPG error: http://deb.debian.org/debian buster InRelease: At least one invalid signature was encountered.
E: The repository 'http://deb.debian.org/debian buster InRelease' is not signed.
W: GPG error: http://deb.debian.org/debian buster-updates InRelease: At least one invalid signature was encountered.
E: The repository 'http://deb.debian.org/debian buster-updates InRelease' is not signed.
W: GPG error: http://security.debian.org/debian-security buster/updates InRelease: At least one invalid signature was encountered.
E: The repository 'http://security.debian.org/debian-security buster/updates InRelease' is not signed.
failed to build: couldn't build "loadgenerator": unable to stream build output: The command '/bin/sh -c apt-get -qq update     &amp;&amp; apt-get install -y --no-install-recommends         curl' returned a non-zero code: 100
</code></pre>

<p>I receive these errors when trying to build loadgenerator.
How can I resolve this issue? </p>

<p>There are a few reasons why you encounter these errors:</p>
<ol>
<li><p>There might be an issue with the existing cache and/or disc space. In order to fix it you need to clear the APT cache by executing: <code>sudo apt-get clean</code> and <code>sudo apt-get update</code>.</p>
</li>
<li><p>The same goes with existing docker images. Execute: <code>docker image prune -f</code> and <code>docker container prune -f</code> in order to remove unused data and free disc space. Executing <code>docker image prune -f</code> will delete all the unused images. To delete some selective images of large size, run <code>docker images</code> and identify the images you want to remove, and then run <code>docker rmi -f &lt;IMAGE-ID1&gt; &lt;IMAGE-ID2&gt; &lt;IMAGE-ID3&gt;</code>.</p>
</li>
<li><p>If you don't care about the security risks, you can try to run the <code>apt-get</code> command with the <code>--allow-unauthenticated</code> or <code>--allow-insecure-repositories</code> flag. According to the <a href="https://manpages.debian.org/stretch/apt/apt-get.8.en.html" rel="noreferrer">docs</a>:</p>
</li>
</ol>
<blockquote>
<p>Ignore if packages can't be authenticated and don't prompt about it.
This can be useful while working with local repositories, but is a
huge security risk if data authenticity isn't ensured in another way
by the user itself.</p>
</blockquote>
<p>Please let me know if that helped.</p>
