Spring Cloud Gateway & Netflix/Eureka - Invalid host lb://

Question

I am getting into the Spring Cloud 2020.0.0 world.

I have a config server, gateway server, eureka server and the first microservice setup and deployed in a dev env where they can all talk to each other. They are config-first, and all successfully pull down property sources from the config server and then register with the eureka server. Because I do not, now at least, have DNS setup for my service apps, I have preferIpAddress: true.

Eureka Instance Registrations

Putting the log levels to trace for spring-cloud-gateway, I see that the discovery client picks up these eureka-registered apps:

    2021-01-28 14:49:28.438 DEBUG 14432 --- [           main] o.s.c.g.r.RouteDefinitionRouteLocator    : RouteDefinition ReactiveCompositeDiscoveryClient_CLOUD-SERVICES-CONFIG applying {pattern=/CLOUD-SERVICES-CONFIG/**} to Path
    
    2021-01-28 14:49:28.476 DEBUG 14432 --- [           main] o.s.c.g.r.RouteDefinitionRouteLocator    : RouteDefinition ReactiveCompositeDiscoveryClient_CLOUD-SERVICES-CONFIG applying filter {regexp=/CLOUD-SERVICES-CONFIG/(?<remaining>.*), replacement=/${remaining}} to RewritePath
    
    2021-01-28 14:49:28.509 DEBUG 14432 --- [           main] o.s.c.g.r.RouteDefinitionRouteLocator    : RouteDefinition matched: ReactiveCompositeDiscoveryClient_CLOUD-SERVICES-CONFIG
and so on...

Running the API gateway locally (I have a deployed instance as well), a Postman GET @ http://localhost:8080/DATA-SERVICES-PERSON-1_0 results in Route matched: ReactiveCompositeDiscoveryClient_DATA-SERVICES-PERSON-1_0 as well as

java.lang.IllegalStateException: Invalid host: lb://DATA-SERVICES-PERSON-1_0
    at org.springframework.cloud.gateway.filter.RouteToRequestUrlFilter.filter(RouteToRequestUrlFilter.java:85) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
    Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):
    |_ checkpoint ⇢ org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter [DefaultWebFilterChain]
    |_ checkpoint ⇢ org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter [DefaultWebFilterChain]
    |_ checkpoint ⇢ HTTP GET "/DATA-SERVICES-PERSON-1_0/" [ExceptionHandlingWebHandler]
Stack trace:
        at org.springframework.cloud.gateway.filter.RouteToRequestUrlFilter.filter(RouteToRequestUrlFilter.java:85) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
        at org.springframework.cloud.gateway.handler.FilteringWebHandler$GatewayFilterAdapter.filter(FilteringWebHandler.java:137) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
        at org.springframework.cloud.gateway.filter.OrderedGatewayFilter.filter(OrderedGatewayFilter.java:44) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
        at org.springframework.cloud.gateway.handler.FilteringWebHandler$DefaultGatewayFilterChain.lambda$filter$0(FilteringWebHandler.java:117) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:44) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Mono.subscribe(Mono.java:4046) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.drain(MonoIgnoreThen.java:173) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:56) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Mono.subscribe(Mono.java:4046) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.drain(MonoIgnoreThen.java:173) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:56) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:157) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxSwitchIfEmpty$SwitchIfEmptySubscriber.onNext(FluxSwitchIfEmpty.java:73) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoNext$NextSubscriber.onNext(MonoNext.java:82) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.innerNext(FluxConcatMap.java:281) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapInner.onNext(FluxConcatMap.java:860) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxMap$MapSubscriber.onNext(FluxMap.java:120) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxSwitchIfEmpty$SwitchIfEmptySubscriber.onNext(FluxSwitchIfEmpty.java:73) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1784) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:151) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxMap$MapSubscriber.onNext(FluxMap.java:120) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoNext$NextSubscriber.onNext(MonoNext.java:82) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.innerNext(FluxConcatMap.java:281) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapInner.onNext(FluxConcatMap.java:860) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxOnErrorResume$ResumeSubscriber.onNext(FluxOnErrorResume.java:79) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onNext(MonoPeekTerminal.java:180) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1784) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoFilterWhen$MonoFilterWhenMain.onNext(MonoFilterWhen.java:149) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Operators$ScalarSubscription.request(Operators.java:2346) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoFilterWhen$MonoFilterWhenMain.onSubscribe(MonoFilterWhen.java:112) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoJust.subscribe(MonoJust.java:54) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Mono.subscribe(Mono.java:4046) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.drain(FluxConcatMap.java:448) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.onNext(FluxConcatMap.java:250) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.onNext(FluxDematerialize.java:98) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.onNext(FluxDematerialize.java:44) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxIterable$IterableSubscription.slowPath(FluxIterable.java:270) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxIterable$IterableSubscription.request(FluxIterable.java:228) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.request(FluxDematerialize.java:127) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.onSubscribe(FluxConcatMap.java:235) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.onSubscribe(FluxDematerialize.java:77) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:164) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:86) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalFluxOperator.subscribe(InternalFluxOperator.java:62) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxDefer.subscribe(FluxDefer.java:54) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Mono.subscribe(Mono.java:4046) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.drain(FluxConcatMap.java:448) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.onSubscribe(FluxConcatMap.java:218) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:164) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:86) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.Mono.subscribe(Mono.java:4046) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.drain(MonoIgnoreThen.java:173) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:56) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.1.jar:3.4.1]
        at reactor.netty.http.server.HttpServer$HttpServerHandle.onStateChange(HttpServer.java:632) ~[reactor-netty-http-1.0.2.jar:1.0.2]
        at reactor.netty.ReactorNetty$CompositeConnectionObserver.onStateChange(ReactorNetty.java:612) ~[reactor-netty-core-1.0.2.jar:1.0.2]
        at reactor.netty.transport.ServerTransport$ChildObserver.onStateChange(ServerTransport.java:453) ~[reactor-netty-core-1.0.2.jar:1.0.2]
        at reactor.netty.http.server.HttpServerOperations.onInboundNext(HttpServerOperations.java:510) ~[reactor-netty-http-1.0.2.jar:1.0.2]
        at reactor.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:94) ~[reactor-netty-core-1.0.2.jar:1.0.2]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:208) ~[reactor-netty-http-1.0.2.jar:1.0.2]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:324) ~[netty-codec-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:296) ~[netty-codec-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:719) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493) ~[netty-transport-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989) ~[netty-common-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.55.Final.jar:4.1.55.Final]
        at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) ~[netty-common-4.1.55.Final.jar:4.1.55.Final]
        at java.base/java.lang.Thread.run(Thread.java:832) ~[na:na]

I've looked over just about every guide out there, where it seemed to make most sense as 2020.0.0 is rather newly released still. What am I missing here? I've tried just about every resource path following the app name, including one that should be what the service's controller would hit on. All goes back to invalid host: lb://..

Answer 1

Recently, I have also had the same issue and I have fix using this

eureka.instance.prefer-ip-address=true

add in your eureka client application.properties

Answer 2

I figured it out, and it is because the Spring app name registered to Eureka for DATA-SERVICES-PERSON-1_0 had an underscore. Removing/replacing that char fixed the issue and it is now properly routing.