redisson: Regression: DNS resolver failing to find valid DNS record

I’m experiencing the same issue with Redisson 3.13.4 which brings in Netty 4.1.51 Final. I’m not using Kubernetes. I’m using docker-compose + docker on a Google Compute Engine VM. It’s failing to resolve an unqualified DNS name on my VPC which is resolved correctly by dig/nslookup/ping/etc.

The container is built from jetty:9-jdk14-slim, which I think (?) means it’s based on debian.

I’m using dirt-simple Redisson configuration:

private val config = Config().apply { useSingleServer().address = "redis://my-host:6379" }

My container’s /etc/resolv.conf looks like this:

`search c.some-domain.internal. google.internal.

nameserver 127.0.0.11

options ndots:0 `

The host VM image is from Debian 10. The host VM’s /etc/resolv.conf looks like this:

`domain c.some-domain.internal

search c.some-domain.internal. google.internal.

nameserver 169.254.169.254`

I worked around it for now by passing a fully-qualified name for my-host. Would love to know why it doesn’t work though.

Setting -Djava.net.preferIPv4Stack=true -Djava.net.preferIPv4Addresses=true did not help. My solution was to use tcp mode for DNS request as reported here.

similar issue happened again @mrniko

JDK 1.8 Redisson 3.9 with default netty (4.1.29.Final)

2018-12-06 17:25:10.746 ERROR 1 --- [redisson-netty-4-1] org.redisson.connection.DNSMonitor       : Unable to resolve mb.y.redis.sohucs.com
io.netty.resolver.dns.DnsResolveContext$SearchDomainUnknownHostException: Search domain query failed. Original hostname: 'someHost.someDomain' failed to resolve 'someHost.someDomain.search.otherDomain' after 2 queries 
  at io.netty.resolver.dns.DnsResolveContext.finishResolve(DnsResolveContext.java:816) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsResolveContext.tryToFinishResolve(DnsResolveContext.java:777) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsResolveContext.query(DnsResolveContext.java:310) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsResolveContext.query(DnsResolveContext.java:299) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsResolveContext.access$500(DnsResolveContext.java:62) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsResolveContext$3.operationComplete(DnsResolveContext.java:356) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:511) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:504) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:483) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:424) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.DefaultPromise.tryFailure(DefaultPromise.java:121) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsQueryContext.setFailure(DnsQueryContext.java:216) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsQueryContext.access$300(DnsQueryContext.java:43) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.resolver.dns.DnsQueryContext$4.run(DnsQueryContext.java:166) [netty-resolver-dns-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.PromiseTask$RunnableAdapter.call(PromiseTask.java:38) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.ScheduledFutureTask.run(ScheduledFutureTask.java:127) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.AbstractEventExecutor.safeExecute(AbstractEventExecutor.java:163) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.SingleThreadEventExecutor.runAllTasks(SingleThreadEventExecutor.java:404) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:446) [netty-transport-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:884) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) [netty-common-4.1.29.Final.jar!/:4.1.29.Final]
  at java.lang.Thread.run(Thread.java:748) [na:1.8.0_181]
Caused by: io.netty.resolver.dns.DnsNameResolverTimeoutException: [/172.16.40.1:53] query timed out after 5000 milliseconds (no stack trace available)

We have also encountered this problem, it seems to be related to this: Racy conntrack and DNS lookup timeouts We are currently attempting to upgrade Alpine to version 3.18.3 and are in the testing phase, not sure if it will work.

I have ready test on alpine 3.18.3 , it can not fix the problem , because redisson dns not implement by musl , it depends on netty dns resovler.

This issue’s fix seems already be included in the 3.18.0 release. redisson-3.18.0