Hi all, as many of you may know, we use PLC4X pretty heavily in Prod. We recently checked our logs and found a lot of entries from PLC4X which are thrown although everything is working. This is something I want to fix (if theres no issue then be silent). We use the S7 driver, but I think this is a general Netty (tcp?) topic.
The mostly logged issue is thrown logged by io.netty.channel.DefaultChannelPipeline and is ``` An exceptionCaught() event was fired, and it reached at the tail of the pipeline. It usually means the last handler in the pipeline did not handle the exception. java.io.IOException: Die Verbindung wurde vom Kommunikationspartner zurückgesetzt at sun.nio.ch.FileDispatcherImpl.read0(Native Method) ~[?:1.8.0_161] at sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:39) ~[?:1.8.0_161] at sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:223) ~[?:1.8.0_161] at sun.nio.ch.IOUtil.read(IOUtil.java:192) ~[?:1.8.0_161] at sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:380) ~[?:1.8.0_161] at io.netty.buffer.PooledUnsafeDirectByteBuf.setBytes(PooledUnsafeDirectByteBuf.java:288) ~[netty-buffer-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1108) ~[netty-buffer-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:345) ~[netty-transport-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:148) [netty-transport-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:645) [netty-transport-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:580) [netty-transport-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:497) [netty-transport-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:459) [netty-transport-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:886) [netty-common-4.1.23.Final.jar!/:4.1.23.Final] at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) [netty-common-4.1.23.Final.jar!/:4.1.23.Final] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_161] ``` Could anyone comment on that, what this means or what we can / should do to handle this? We get this entry nearly 100 times a hour (for multiple hundreds requests).
