Can you show your extended code? Gruss Bernd -- http://bernd.eckenfels.net ________________________________ From: undertow-dev-bounces(a)lists.jboss.org <undertow-dev-bounces(a)lists.jboss.org&gt; on behalf of Steve Hu <stevehu(a)gmail.com&gt; Sent: Monday, October 16, 2017 11:49:26 PM To: Undertow Developers Subject: [undertow-dev] Reverse proxy with https connections I am extending the ReverseProxyServer example to connect down stream servers that listen to https and got the following error on the proxy server. After debugging into it, I realized that the ssl is null when UndertowClient tries to create connection to the downstream server. I am wondering who is responsible for creating this ssl object. Where the certificates should be loaded? Thanks, Steve proxy_1 | 17:37:12.430 [XNIO-1 I/O-4] DEBUG io.undertow.request failed - Failed to connect proxy_1 | java.io.IOException: UT000065: SSL must be specified to connect to a https URL proxy_1 | at io.undertow.client.http.HttpClientProvider.connect(HttpClientProvider.java:94) proxy_1 | at io.undertow.client.UndertowClient.connect(UndertowClient.java:157) proxy_1 | at io.undertow.server.handlers.proxy.ProxyConnectionPool.openConnection(ProxyConnectionPool.java:273) proxy_1 | at io.undertow.server.handlers.proxy.ProxyConnectionPool.connect(ProxyConnectionPool.java:527) proxy_1 | at io.undertow.server.handlers.proxy.LoadBalancingProxyClient.getConnection(LoadBalancingProxyClient.java:301) proxy_1 | at io.undertow.server.handlers.proxy.ProxyHandler$ProxyClientHandler.run(ProxyHandler.java:292) proxy_1 | at org.xnio.nio.WorkerThread.safeRun(WorkerThread.java:582) proxy_1 | at org.xnio.nio.WorkerThread.run(WorkerThread.java:466)