Logstash execption in pipeline worker

Hi, I have 4 logstash ( v7.4.2) services on 4 separate VMs. The logstash services keeps crashing after a while or few hours. This is the config:

filter {
        ip2location {
              source => "clientip"
              database => "/etc/logstash/conf.d/IP-COUNTRY-ISP.BIN"
                    }
}

It's look like there is something about ip2location plugin because the error points to that filter. This is the log:

[2020-12-31T18:18:15,874][ERROR][org.logstash.execution.WorkerLoop][main] Exception in pipelineworker, the pipeline stopped processing new events, please check your filter configuration and restart Logstash.
java.util.ConcurrentModificationException: null
        at java.util.IdentityHashMap.forEach(IdentityHashMap.java:1358) ~[?:?]
        at org.logstash.Rubyfier.deepMap(Rubyfier.java:71) ~[logstash-core.jar:?]
        at org.logstash.Rubyfier.lambda$initConverters$8(Rubyfier.java:99) ~[logstash-core.jar:?]
        at org.logstash.Rubyfier.deep(Rubyfier.java:53) ~[logstash-core.jar:?]
        at org.logstash.ext.JrubyEventExtLibrary$RubyEvent.ruby_get_field(JrubyEventExtLibrary.java:85) ~[logstash-core.jar:?]
        at usr.share.logstash.vendor.bundle.jruby.$2_dot_5_dot_0.gems.logstash_minus_filter_minus_ip2location_minus_2_dot_1_dot_4.lib.logstash.filters.ip2location.RUBY$method$filter$0(/usr/share/logstash/vendor/bundle/jruby/2.5.0/gems/logstash-filter-ip2location-2.1.4/lib/logstash/filters/ip2location.rb:50) ~[?:?]
        at org.jruby.internal.runtime.methods.CompiledIRMethod.call(CompiledIRMethod.java:117) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.internal.runtime.methods.MixedModeIRMethod.call(MixedModeIRMethod.java:156) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.ir.targets.InvokeSite.fail(InvokeSite.java:253) ~[jruby-complete-9.2.8.0.jar:?]
        at usr.share.logstash.logstash_minus_core.lib.logstash.filters.base.RUBY$method$do_filter$0(/usr/share/logstash/logstash-core/lib/logstash/filters/base.rb:143) ~[?:?]
        at org.jruby.internal.runtime.methods.CompiledIRMethod.call(CompiledIRMethod.java:117) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.internal.runtime.methods.MixedModeIRMethod.call(MixedModeIRMethod.java:156) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.ir.targets.InvokeSite.fail(InvokeSite.java:253) ~[jruby-complete-9.2.8.0.jar:?]
        at usr.share.logstash.logstash_minus_core.lib.logstash.filters.base.RUBY$block$multi_filter$1(/usr/share/logstash/logstash-core/lib/logstash/filters/base.rb:162) ~[?:?]
        at org.jruby.runtime.CompiledIRBlockBody.yieldDirect(CompiledIRBlockBody.java:146) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.runtime.BlockBody.yield(BlockBody.java:114) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.runtime.Block.yield(Block.java:170) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.RubyArray.each(RubyArray.java:1800) ~[jruby-complete-9.2.8.0.jar:?]
        at usr.share.logstash.logstash_minus_core.lib.logstash.filters.base.RUBY$method$multi_filter$0(/usr/share/logstash/logstash-core/lib/logstash/filters/base.rb:159) ~[?:?]
        at org.jruby.internal.runtime.methods.CompiledIRMethod.call(CompiledIRMethod.java:117) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.internal.runtime.methods.MixedModeIRMethod.call(MixedModeIRMethod.java:156) ~[jruby-complete-9.2.8.0.jar:?]
        at org.jruby.internal.runtime.methods.DynamicMethod.call(DynamicMethod.java:200) ~[jruby-complete-9.2.8.0.jar:?]
        at org.logstash.config.ir.compiler.FilterDelegatorExt.doMultiFilter(FilterDelegatorExt.java:99) ~[logstash-core.jar:?]
        at org.logstash.config.ir.compiler.AbstractFilterDelegatorExt.multiFilter(AbstractFilterDelegatorExt.java:115) ~[logstash-core.jar:?]
        at org.logstash.generated.CompiledDataset110.compute(Unknown Source) ~[?:?]
        at org.logstash.generated.CompiledDataset111.compute(Unknown Source) ~[?:?]
        at org.logstash.generated.CompiledDataset112.compute(Unknown Source) ~[?:?]
        at org.logstash.generated.CompiledDataset113.compute(Unknown Source) ~[?:?]
        at org.logstash.generated.CompiledDataset114.compute(Unknown Source) ~[?:?]
        at org.logstash.generated.CompiledDataset115.compute(Unknown Source) ~[?:?]
        at org.logstash.generated.CompiledDataset116.compute(Unknown Source) ~[?:?]
        at org.logstash.generated.CompiledDataset117.compute(Unknown Source) ~[?:?]
        at org.logstash.execution.WorkerLoop.run(WorkerLoop.java:64) [logstash-core.jar:?]
        at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:?]
        at jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:?]
        at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:?]
        at java.lang.reflect.Method.invoke(Method.java:566) ~[?:?]
        at org.jruby.javasupport.JavaMethod.invokeDirectWithExceptionHandling(JavaMethod.java:440) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.javasupport.JavaMethod.invokeDirect(JavaMethod.java:304) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.java.invokers.InstanceMethodInvoker.call(InstanceMethodInvoker.java:36) [jruby-complete-9.2.8.0.jar:?]
        at usr.share.logstash.logstash_minus_core.lib.logstash.java_pipeline.RUBY$block$start_workers$2(/usr/share/logstash/logstash-core/lib/logstash/java_pipeline.rb:243) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.runtime.CompiledIRBlockBody.callDirect(CompiledIRBlockBody.java:136) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.runtime.IRBlockBody.call(IRBlockBody.java:77) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.runtime.Block.call(Block.java:129) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.RubyProc.call(RubyProc.java:295) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.RubyProc.call(RubyProc.java:274) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.RubyProc.call(RubyProc.java:270) [jruby-complete-9.2.8.0.jar:?]
        at org.jruby.internal.runtime.RubyRunnable.run(RubyRunnable.java:105) [jruby-complete-9.2.8.0.jar:?]
        at java.lang.Thread.run(Thread.java:834) [?:?]
[2020-12-31T18:18:15,952][FATAL][logstash.runner          ] An unexpected error occurred! {:error=>java.lang.IllegalStateException: java.util.ConcurrentModificationException, :backtrace=>["org.logstash.execution.WorkerLoop.run(org/logstash/execution/WorkerLoop.java:85)", "jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)", "jdk.internal.reflect.NativeMethodAccessorImpl.invoke(jdk/internal/reflect/NativeMethodAccessorImpl.java:62)", "jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(jdk/internal/reflect/DelegatingMethodAccessorImpl.java:43)", "java.lang.reflect.Method.invoke(java/lang/reflect/Method.java:566)", "org.jruby.javasupport.JavaMethod.invokeDirectWithExceptionHandling(org/jruby/javasupport/JavaMethod.java:440)", "org.jruby.javasupport.JavaMethod.invokeDirect(org/jruby/javasupport/JavaMethod.java:304)", "usr.share.logstash.logstash_minus_core.lib.logstash.java_pipeline.start_workers(/usr/share/logstash/logstash-core/lib/logstash/java_pipeline.rb:243)", "org.jruby.RubyProc.call(org/jruby/RubyProc.java:295)", "org.jruby.RubyProc.call(org/jruby/RubyProc.java:274)", "org.jruby.RubyProc.call(org/jruby/RubyProc.java:270)", "java.lang.Thread.run(java/lang/Thread.java:834)"]}
[2020-12-31T18:18:16,005][ERROR][org.logstash.Logstash    ] java.lang.IllegalStateException: Logstash stopped processing because of an error: (SystemExit) exit

What is the problem ? Thank you

I suggest you open an issue against the ip2location plugin. It has had problems with this in the past.