Spring Cloud Consul config watch keeps generating warning messages

[bryanxtong]

Describe the bug
Spring Cloud Consul config 5.0.0 keeps giving us warnings messages when enabling config watches for configuration, and the config data can be found with config/application/data(data is the key).

[
{
"key": "config/",
"flags": 0,
"value": ""
},
{
"key": "config/application/",
"flags": 0,
"value": ""
},
{
"key": "config/application/data",
"flags": 0,
"value": "bG9nZ2luZzoKICBsZXZlbDoKICAgIG9yZy5zcHJpbmdmcmFtZXdvcmsuY29yZS5lbnY6IERFQlVH"
},
{
"key": "config/gateway/",
"flags": 0,
"value": ""
},
{
"key": "config/gateway/data",
"flags": 0,
"value": ""
}
]

Sample

gateway.zip

The logs are as below. and if set fail fast, It will produce errors. and actually, we had provided the config items in consul KV.

2026-01-26T18:44:20.470+08:00 WARN 36468 --- [gateway] [TaskScheduler-1] o.s.cloud.consul.config.ConfigWatch : Error querying consul Key/Values for context 'config/gateway/'. Message: I/O error on GET request for "http://localhost:8500/v1/kv/config/gateway/": null
2026-01-26T18:44:30.475+08:00 WARN 36468 --- [gateway] [ctor-http-nio-5] r.netty.http.client.HttpClientConnect : [74757339-1, L:/127.0.0.1:62403 - R:localhost/127.0.0.1:8500] The connection observed an error

io.netty.handler.timeout.ReadTimeoutException

2026-01-26T18:44:30.475+08:00 WARN 36468 --- [gateway] [TaskScheduler-1] o.s.cloud.consul.config.ConfigWatch : Error querying consul Key/Values for context 'config/application/'. Message: I/O error on GET request for "http://localhost:8500/v1/kv/config/application/": null
2026-01-26T18:45:10.488+08:00 WARN 36468 --- [gateway] [ctor-http-nio-7] r.netty.http.client.HttpClientConnect : [61d86986-1, L:/127.0.0.1:62448 - R:localhost/127.0.0.1:8500] The connection observed an error

io.netty.handler.timeout.ReadTimeoutException

2026-01-26T18:45:10.489+08:00 WARN 36468 --- [gateway] [TaskScheduler-1] o.s.cloud.consul.config.ConfigWatch : Error querying consul Key/Values for context 'config/gateway/'. Message: I/O error on GET request for "http://localhost:8500/v1/kv/config/gateway/": null
2026-01-26T18:45:20.504+08:00 WARN 36468 --- [gateway] [ctor-http-nio-2] r.netty.http.client.HttpClientConnect : [df3e3ad3-25, L:/127.0.0.1:62388 - R:localhost/127.0.0.1:8500] The connection observed an error

io.netty.handler.timeout.ReadTimeoutException

[viktorgunnarson]

We're experiencing the same issue, is there any progress on this?

[viktorgunnarson]

This is the full error we're seeing:

ERROR  [configWatchTaskSched] 2026-04-22T03:33:36.529Z  Fail fast is set and there was an error reading configuration from consul.
ERROR  [configWatchTaskSched] 2026-04-22T03:33:36.529Z  Unexpected error occurred in scheduled task
org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://169.254.1.1:8500/v1/kv/team/config/shared/features/app,sandbox/": null
        at org.springframework.web.client.DefaultRestClient$DefaultRequestBodyUriSpec.createResourceAccessException(DefaultRestClient.java:776)
        at org.springframework.web.client.DefaultRestClient$DefaultRequestBodyUriSpec.exchangeInternal(DefaultRestClient.java:624)
        at org.springframework.web.client.DefaultRestClient$DefaultRequestBodyUriSpec.exchange(DefaultRestClient.java:572)
        at org.springframework.web.client.RestClient$RequestHeadersSpec.exchange(RestClient.java:747)
        at org.springframework.web.client.DefaultRestClient$DefaultResponseSpec.executeAndExtract(DefaultRestClient.java:921)
        at org.springframework.web.client.DefaultRestClient$DefaultResponseSpec.toEntityInternal(DefaultRestClient.java:867)
        at org.springframework.web.client.DefaultRestClient$DefaultResponseSpec.toEntity(DefaultRestClient.java:863)
        at org.springframework.web.client.support.RestClientAdapter.exchangeForEntity(RestClientAdapter.java:86)
        at org.springframework.web.service.invoker.HttpServiceMethod$ExchangeResponseFunction.lambda$create$3(HttpServiceMethod.java:440)
        at org.springframework.web.service.invoker.HttpServiceMethod$ExchangeResponseFunction.execute(HttpServiceMethod.java:401)
        at org.springframework.web.service.invoker.HttpServiceMethod.invoke(HttpServiceMethod.java:136)
        at org.springframework.web.service.invoker.HttpServiceProxyFactory$HttpServiceMethodInterceptor.invoke(HttpServiceProxyFactory.java:300)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
        at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:222)
        at jdk.proxy2/jdk.proxy2.$Proxy18.getKVValues(Unknown Source)
        at org.springframework.cloud.consul.config.ConfigWatch.watchConfigKeyValues(ConfigWatch.java:159)
        at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54)
        at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:545)
        at java.base/java.util.concurrent.FutureTask.runAndReset(FutureTask.java:369)
        at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:310)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1090)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614)
        at java.base/java.lang.Thread.run(Thread.java:1474)
Caused by: java.io.IOException
        at org.springframework.http.client.ReactorClientHttpRequest.convertException(ReactorClientHttpRequest.java:166)
        at org.springframework.http.client.ReactorClientHttpRequest.executeInternal(ReactorClientHttpRequest.java:134)
        at org.springframework.http.client.AbstractStreamingClientHttpRequest.executeInternal(AbstractStreamingClientHttpRequest.java:87)
        at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:80)
        at org.springframework.web.client.DefaultRestClient$DefaultRequestBodyUriSpec.exchangeInternal(DefaultRestClient.java:614)
        ... 21 more
Caused by: io.netty.handler.timeout.ReadTimeoutException

[steroid]

Seems read timeout for ConsulClient is 10s, but config watch waiting by default for 55s

[bryanxtong]

We're experiencing the same issue, is there any progress on this?

spring:
application:
  name: gateway
config:
  import: 'optional:consul:'
cloud:
  consul:
    host: ${SPRING_CLOUD_CONSUL_HOST:localhost}
    port: 8500
    config:
      format: YAML
      default-context: application
      prefixes:
        - config
      fail-fast: true
      watch:
        delay: 3000
        enabled: true
        wait-time: 5 #让 HTTP 超时 > Consul wait 时间
    enabled: true
    discovery:
      query-passing: true