启动正常访问服务报错：01:23:45.479 [NettyServerWorker-3-4] WARN i.n.channel.DefaultChannelPipeline - 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.

[hyberbin]

01:23:45.479 [NettyServerWorker-3-4] WARN i.n.channel.DefaultChannelPipeline - 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.
io.netty.channel.ChannelPipelineException: org.apache.dubbo.remoting.transport.netty4.NettyCodecAdapter$InternalDecoder.handlerRemoved() has thrown an exception.
at io.netty.channel.DefaultChannelPipeline.callHandlerRemoved0(DefaultChannelPipeline.java:676)
at io.netty.channel.DefaultChannelPipeline.destroyDown(DefaultChannelPipeline.java:922)
at io.netty.channel.DefaultChannelPipeline.destroyUp(DefaultChannelPipeline.java:888)
at io.netty.channel.DefaultChannelPipeline.destroy(DefaultChannelPipeline.java:880)
at io.netty.channel.DefaultChannelPipeline.access$700(DefaultChannelPipeline.java:46)
at io.netty.channel.DefaultChannelPipeline$HeadContext.channelUnregistered(DefaultChannelPipeline.java:1416)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelUnregistered(AbstractChannelHandlerContext.java:181)
at io.netty.channel.AbstractChannelHandlerContext.invokeChannelUnregistered(AbstractChannelHandlerContext.java:167)
at io.netty.channel.DefaultChannelPipeline.fireChannelUnregistered(DefaultChannelPipeline.java:865)
at io.netty.channel.AbstractChannel$AbstractUnsafe$8.run(AbstractChannel.java:830)
at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163)
at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:404)
at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:465)
at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:884)
at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
at java.lang.Thread.run(Thread.java:748)
Caused by: io.netty.util.IllegalReferenceCountException: refCnt: 0, decrement: 1
at io.netty.util.internal.ReferenceCountUpdater.toLiveRealRefCnt(ReferenceCountUpdater.java:74)
at io.netty.util.internal.ReferenceCountUpdater.release(ReferenceCountUpdater.java:138)
at io.netty.buffer.AbstractReferenceCountedByteBuf.release(AbstractReferenceCountedByteBuf.java:100)
at io.netty.handler.codec.ByteToMessageDecoder.handlerRemoved(ByteToMessageDecoder.java:238)
at io.netty.channel.DefaultChannelPipeline.callHandlerRemoved0(DefaultChannelPipeline.java:670)
... 15 common frames omitte

[hyberbin]

dubbo版本：2.7.3
服务器容器部署：操作系统centos ，Linux version 3.10.0-327.el7.x86_64 (builder@kbuilder.dev.centos.org) (gcc version 4.8.3 20140911 (Red Hat 4.8.3-9) (GCC) ) #1 SMP Thu Nov 19 22:10:57 UTC 2015
MemTotal: 32780996 kB
MemFree: 15476736 kB
MemAvailable: 25034288 kB
Buffers: 682756 kB
Cached: 8872728 kB

[hyberbin]

升级新版本后没有复现