add proxy configuration to troubleshooting guide

docs/self-managed/modeler/web-modeler/troubleshooting/troubleshoot-proxy-configuration.md

@@ -0,0 +1,30 @@
+---
+id: troubleshoot-proxy-configuration
+title: "Troubleshoot proxy configuration issues"
+sidebar_label: "Proxy configuration"
+description: "Troubleshooting guide for issues caused by incorrect proxy configuration in Web Modeler."
+---
+
+Troubleshoot and resolve issues in Web Modeler caused by incorrect or incomplete proxy configuration.
+
+## Issue
+
+Users experience a variety of failures when Web Modeler attempts to communicate with external services. These issues can manifest as:
+
+- Failed authentication due to the inability to access the JWKS (JSON Web Key Set) endpoint. Error message: “Expected 200 OK from the JSON Web Key Set HTTP response.”
+- Failure to reach other external services, such as the Camunda Marketplace.
+
+## Cause
+
+Proxy settings must be correctly configured for Web Modeler to route outgoing requests through a network proxy. Common issues occur when:
+
+- The proxy server is not properly configured or unreachable.
+- Requests to external services are being blocked by the proxy configuration.
+- Authentication requests, such as those to the OIDC provider, fail when the JWKS endpoint is unreachable via the proxy.
+
+## Resolution
+
+Ensure correct proxy configuration for both `webapp` and `restapi` components.
+
+- For the `webapp` component, proxy configuration is handled via environment variables (`http_proxy`, `https_proxy`, `no_proxy`).
+- For the `restapi` component, proxy configuration is handled via JVM settings, such as JAVA_OPTS (e.g., -Dhttp.proxyHost, -Dhttps.proxyPort).

sidebars.js

@@ -1548,6 +1548,7 @@ module.exports = {
  "self-managed/modeler/web-modeler/troubleshooting/troubleshoot-database-connection",
  "self-managed/modeler/web-modeler/troubleshooting/troubleshoot-zeebe-connection",
  "self-managed/modeler/web-modeler/troubleshooting/troubleshoot-missing-data",
+ "self-managed/modeler/web-modeler/troubleshooting/troubleshoot-proxy-configuration",
  ],
  },
  ],