Thanks Erick, I was waiting your Day time appears to get suggestion because you are very spontaneous for this great open source community.
1. Did you recompile and redistriburte your custom component? * Yes* 2. Did you take the solrconfig that came with 7.5 and modify it rather than copy your 5.3 solrconfig? No, We have adjusted existing 5.3.1 config when we used for couple years to SOLR 7.5.0. 3. Did you reindex from scratch with 7x? Lucene/Solr guarantees only one major version back-compat. Yes, We have done Full Reindexing. No issues noticed with reindex. All works as expected in the flow of /select request handler. Noticed one stuff below changed in SOLR 7.5.0 All Shard Requests are distributed back to custom component flow instead default components. // for distributed queries that don’t include shards.qt, use the original path // as the default but operators need to update their luceneMatchVersion to enable // this behavior since it did not work this way prior to 5.1 if (req.getCore().getSolrConfig().luceneMatchVersion.onOrAfter(Version.LUCENE_5_1_0)) { String reqPath = (String) req.getContext().get(PATH); if (!“/select”.equals(reqPath)) { params.set(CommonParams.QT, reqPath); } // else if path is /select, then the qt gets passed thru if set } else { // this is the pre-5.1 behavior, which translates to sending the shard request to /select params.remove(CommonParams.QT); } Below some portion of debug log. Enabled Debug and noticed that for the custom component handler flow for all shard request, "PARSE_QUERY":{ "http://<>_shard26_replica_n9/":{ "QTime":"27", "ElapsedTime":"28", "RequestPurpose":"GET_TERM_STATS", "NumFound":"<>", "Response":"{responseHeader={zkConnected=true,xqs=best,info={},status=0,QTime=27},response={numFound= "EXECUTE_QUERY":{ "http://<>_shard3_replica_n27/":{ "QTime":"26", "ElapsedTime":"26", "RequestPurpose":"GET_TOP_IDS,GET_FIELDS,GET_DEBUG,SET_TERM_STATS", "NumFound":"<>", "Response":"{responseHeader={zkConnected=true,xqs=best,info={},status=0,QTime=26},response={numFound= *But when Default(/select) flow goes,* "PARSE_QUERY":{ "http://<>_shard24_replica_n6/":{ "QTime":"0", "ElapsedTime":"1", "RequestPurpose":"GET_TERM_STATS", "Response":"{responseHeader={zkConnected=true,status=0,QTime=0,params={df=all,distrib=false,debug=[false, timing, track],shards.purpose=3276 } "EXECUTE_QUERY":{ "http://<>_shard30_replica_n1/":{ "QTime":"17", "ElapsedTime":"19", "RequestPurpose":"GET_TOP_IDS,SET_TERM_STATS", "NumFound":"316605", "Response":"{responseHeader={zkConnected=true,status=0,QTime=17,params={df=all,distrib=false,fl=[id, score],shards.purpose=16388 is there any documentation about to read all these flow purpose and understand better -- Sent from: http://lucene.472066.n3.nabble.com/Solr-User-f472068.html