Hi we are using jboss EAP in production as an API gateway and we have a problem with the communication to some of our servers. We can see this in our logs. 2019-09-13 08:57:31,337 +0200 DEBUG [io.undertow.client] (default-undertow I/O-21) Connection closed with IOException: java.io.IOException: Connection reset by peer at sun.nio.ch.FileDispatcherImpl.read0(Native Method) [rt.jar:1.8.0_222] at sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:39) [rt.jar:1.8.0_222] at sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:223) [rt.jar:1.8.0_222] at sun.nio.ch.IOUtil.read(IOUtil.java:192) [rt.jar:1.8.0_222] at sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:380) [rt.jar:1.8.0_222] at org.xnio.nio.NioSocketConduit.read(NioSocketConduit.java:289) [xnio-nio.jar:3.4.3.Final-redhat-1] at org.xnio.conduits.PushBackStreamSourceConduit.read(PushBackStreamSourceConduit.java:52) [xnio-api.jar:3.4.3.Final-redhat-1] at org.xnio.conduits.ConduitStreamSourceChannel.read(ConduitStreamSourceChannel.java:127) [xnio-api.jar:3.4.3.Final-redhat-1] at io.undertow.client.http.HttpClientConnection$ClientReadListener.handleEvent(HttpClientConnection.java:510) at io.undertow.client.http.HttpClientConnection$ClientReadListener.handleEvent(HttpClientConnection.java:473) at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92) [xnio-api.jar:3.4.3.Final-redhat-1] at org.xnio.conduits.ReadReadyHandler$ChannelListenerHandler.readReady(ReadReadyHandler.java:66) [xnio-api.jar:3.4.3.Final-redhat-1] at org.xnio.nio.NioSocketConduit.handleReady(NioSocketConduit.java:89) [xnio-nio.jar:3.4.3.Final-redhat-1] at org.xnio.nio.WorkerThread.run(WorkerThread.java:567) [xnio-nio.jar:3.4.3.Final-redhat-1] 2019-09-13 08:57:31,339 +0200 ERROR [io.undertow.proxy] (default-undertow I/O-21) UT005028: Proxy request to /*****/******* failed: java.io.IOException: UT001000: Connection closed at io.undertow.client.http.HttpClientConnection$ClientReadListener.handleEvent(HttpClientConnection.java:516) at io.undertow.client.http.HttpClientConnection$ClientReadListener.handleEvent(HttpClientConnection.java:473) at org.xnio.ChannelListeners.invokeChannelListener(ChannelListeners.java:92) [xnio-api.jar:3.4.3.Final-redhat-1] at org.xnio.conduits.ReadReadyHandler$ChannelListenerHandler.readReady(ReadReadyHandler.java:66) [xnio-api.jar:3.4.3.Final-redhat-1] at org.xnio.nio.NioSocketConduit.handleReady(NioSocketConduit.java:89) [xnio-nio.jar:3.4.3.Final-redhat-1] at org.xnio.nio.WorkerThread.run(WorkerThread.java:567) [xnio-nio.jar:3.4.3.Final-redhat-1] The client receives a HTTP 503 response, any advice on how we can solve this is very welcome. Also it looks like we are setting up a lot of new connections, I was thinking it would be kept alive a bit longer. 2019-09-13 08:57:46,696 +0200 DEBUG [io.undertow.client] (default-undertow I/O-11) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:47,019 +0200 DEBUG [io.undertow.client] (default-undertow I/O-17) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:47,117 +0200 DEBUG [io.undertow.client] (default-undertow I/O-7) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:47,427 +0200 DEBUG [io.undertow.client] (default-undertow I/O-9) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:47,552 +0200 DEBUG [io.undertow.client] (default-undertow I/O-9) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:47,552 +0200 DEBUG [io.undertow.client] (default-undertow I/O-6) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:47,634 +0200 DEBUG [io.undertow.client] (default-undertow I/O-28) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:48,200 +0200 DEBUG [io.undertow.client] (default-undertow I/O-9) Connection to ********************:8080 was closed by the target server 2019-09-13 08:57:48,205 +0200 DEBUG [io.undertow.client] (default-undertow I/O-15) Connection to ********************8080 was closed by the target server