Connection server fails to connect ThingWorx cluster via service discovery, the log reported "connection refused"

ERROR c.t.s.i.transport.MuxingBytesChannel - Error refilling connections on [channel: null, endpoint ws://localhost:8080/Thingworx/WS, uri: ws://localhost:8080/Thingworx/WS] failed : io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: localhost/127.0.0.1:8080
java.util.concurrent.CompletionException: io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: localhost/127.0.0.1:8080
    at java.base/java.util.concurrent.CompletableFuture.encodeThrowable(CompletableFuture.java:331)
    at java.base/java.util.concurrent.CompletableFuture.completeThrowable(CompletableFuture.java:346)
    at java.base/java.util.concurrent.CompletableFuture.uniWhenComplete(CompletableFuture.java:870)
    at java.base/java.util.concurrent.CompletableFuture$UniWhenComplete.tryFire(CompletableFuture.java:837)
    at java.base/java.util.concurrent.CompletableFuture.postComplete(CompletableFuture.java:506)
    at java.base/java.util.concurrent.CompletableFuture.completeExceptionally(CompletableFuture.java:2088)
    at com.thingworx.sdk.impl.transport.netty.NettyBytesChannel.lambda$startConnect$4(NettyBytesChannel.java:271)
    at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:577)
    at io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:570)
    at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:549)
    at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:490)
    at io.netty.util.concurrent.DefaultPromise.setValue0(DefaultPromise.java:615)
    at io.netty.util.concurrent.DefaultPromise.setFailure0(DefaultPromise.java:608)
    at io.netty.util.concurrent.DefaultPromise.tryFailure(DefaultPromise.java:117)
    at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.fulfillConnectPromise(AbstractNioChannel.java:321)
    at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:337)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:702)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:650)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:576)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
    at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989)
    at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
    at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection refused: localhost/127.0.0.1:8080
Caused by: java.net.ConnectException: Connection refused
    at java.base/sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
    at java.base/sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:777)
    at io.netty.channel.socket.nio.NioSocketChannel.doFinishConnect(NioSocketChannel.java:330)
    at io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:334)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:702)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:650)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:576)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493)
    at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989)
    at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
    at java.base/java.lang.Thread.run(Thread.java:829)