https://vegatron.engineering/tags/tls/Recent content in Tls on Vegatron 🌈✨Hugoen-usSat, 11 Jul 2026 00:00:00 +0000https://vegatron.engineering/posts/checking-certs/Sat, 11 Jul 2026 00:00:00 +0000https://vegatron.engineering/posts/checking-certs/<p>Even among microservices it&rsquo;s prudent to use HTTPS to communicate. It builds more trust in the system.</p> <h1 id="unhelpful-error">Unhelpful error</h1> <p>But when the certificates fail in some way the error is quite unhelpful.</p> <p>There&rsquo;s no information about which certificate failed, or why it failed. The stacktrace and exception message do not help to diagnose the problem:</p> <div class="code-block"> <button type="button" class="code-copy-btn" data-copy-target="code-block-0-src" aria-label="Copy code">Copy</button> <textarea id="code-block-0-src" class="code-src-raw" hidden tabindex="-1" aria-hidden="true">sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target at java.base/sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:148) ... at io.ktor.network.tls.TLSClientHandshake.handleCertificatesAndKeys(TLSClientHandshake.kt:257) ...</textarea> <div class="code-reveal-clip"><pre tabindex="0"><code>sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target at java.base/sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:148) ... at io.ktor.network.tls.TLSClientHandshake.handleCertificatesAndKeys(TLSClientHandshake.kt:257) ...</code></pre></div> </div> <h1 id="certificate-issues">Certificate issues</h1> <p>We hit this exact problem recently, when an upstream system had a certificate issue.</p>