Rajeev Massey ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=63348a0... ) *updated* an issue Hibernate Search ( https://hibernate.atlassian.net/browse/HSEARCH?atlOrigin=eyJpIjoiMDRjOTNl... ) / Bug ( https://hibernate.atlassian.net/browse/HSEARCH-4709?atlOrigin=eyJpIjoiMDR... ) HSEARCH-4709 ( https://hibernate.atlassian.net/browse/HSEARCH-4709?atlOrigin=eyJpIjoiMDR... ) Custom HttpClientConfigurer Code unreachable ( https://hibernate.atlassian.net/browse/HSEARCH-4709?atlOrigin=eyJpIjoiMDR... ) Change By: Rajeev Massey ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=63348a0... ) As per the documentation the HttpClientConfigurer code is not reachable therefore UUID in the log trace is not being added. public class HttpClientConfigurer implements ElasticsearchHttpClientConfigurer { @Override public void configure(ElasticsearchHttpClientConfigurationContext context) { HttpAsyncClientBuilder clientBuilder = context.clientBuilder(); clientBuilder.addInterceptorFirst((HttpRequestInterceptor) (request, context12) -> { MDC.put("correlationId", UUID.randomUUID().toString()); }); clientBuilder.addInterceptorFirst((HttpResponseInterceptor) (response, context1) -> { MDC.put("correlationId", UUID.randomUUID().toString()); }); } } hibernate.search.backend.client.configurer =class:com.example.configuration.HttpClientConfigurer Note : MDC - > A Mapped Diagnostic Context, or MDC in short, is an instrument for distinguishing interleaved log output from different sources. Log output is typically interleaved when a server handles multiple clients near-simultaneously. MDC.put("correlationId", UUID.randomUUID().toString()); add adds the correlationId UUID to the logging context. *Main Goal is to generate logs with UUID for better tracing* ( https://hibernate.atlassian.net/browse/HSEARCH-4709#add-comment?atlOrigin... ) Add Comment ( https://hibernate.atlassian.net/browse/HSEARCH-4709#add-comment?atlOrigin... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100207- sha1:ee9e30a )