To be more precisely and provide some more details, i tried to simplify the problem by using the Solr-examples that were delivered with the solr.... So i started bin/solr -e cloud, using 2 nodes, 2 shards and replication of 2.
To understand the following, it might be important to know, which ports are used: node 1: 8983 (leader for shard1 and shard2) node 2: 7574 (no leader at all) In this example i searched for 3 terms in the following order: first on node 1 (8983 - leader) and then on node 2 (7574). Sample1 (q=test): http://localhost:8983/solr/gettingstarted/select?indent=on&q=test&wt=json produced logs: 1) [gettingstarted_shard1_replica_n1] webapp=/solr path=/select params={df=_text_&distrib=false&fl=id&fl=score&shards.purpose=4&start=0&fsv=true&shard.url=http://127.0.1.1:7574/solr/gettingstarted_shard1_replica_n1/|http://127.0.1.1:8983/solr/gettingstarted_shard1_replica_n2/&rows=10&version=2&q=test&NOW=1512474523045&isShard=true&wt=javabin} hits=0 status=0 QTime=1 2) [gettingstarted_shard2_replica_n4] webapp=/solr path=/select params={df=_text_&distrib=false&fl=id&fl=score&shards.purpose=4&start=0&fsv=true&shard.url=http://127.0.1.1:7574/solr/gettingstarted_shard2_replica_n4/|http://127.0.1.1:8983/solr/gettingstarted_shard2_replica_n6/&rows=10&version=2&q=test&NOW=1512474523045&isShard=true&wt=javabin} hits=0 status=0 QTime=1 http://localhost:7574/solr/gettingstarted/select?indent=on&q=test&wt=json produced logs: 1) [gettingstarted_shard1_replica_n1] webapp=/solr path=/select params={q=test&indent=on&wt=json} hits=0 status=0 QTime=17 ############################################################################################################################## ############################################################################################################################## Sample2 (q=foo): http://localhost:8983/solr/gettingstarted/select?indent=on&q=foo&wt=json produced logs: 1) [gettingstarted_shard1_replica_n1] webapp=/solr path=/select params={df=_text_&distrib=false&fl=id&fl=score&shards.purpose=4&start=0&fsv=true&shard.url=http://127.0.1.1:7574/solr/gettingstarted_shard1_replica_n1/|http://127.0.1.1:8983/solr/gettingstarted_shard1_replica_n2/&rows=10&version=2&q=foo&NOW=1512474569299&isShard=true&wt=javabin} hits=0 status=0 QTime=0 http://localhost:7574/solr/gettingstarted/select?indent=on&q=foo&wt=json produced logs: 1) [gettingstarted_shard2_replica_n4] webapp=/solr path=/select params={q=foo&indent=on&wt=json} hits=0 status=0 QTime=13 ############################################################################################################################## ############################################################################################################################## Sample3 (q=test) NOTE- its the same query as in sample1: http://localhost:8983/solr/gettingstarted/select?indent=on&q=test&wt=json produced logs: 1) [gettingstarted_shard2_replica_n4] webapp=/solr path=/select params={df=_text_&distrib=false&fl=id&fl=score&shards.purpose=4&start=0&fsv=true&shard.url=http://127.0.1.1:7574/solr/gettingstarted_shard2_replica_n4/|http://127.0.1.1:8983/solr/gettingstarted_shard2_replica_n6/&rows=10&version=2&q=test&NOW=1512474643732&isShard=true&wt=javabin} hits=0 status=0 QTime=0 http://localhost:7574/solr/gettingstarted/select?indent=on&q=test&wt=json produced logs: 1) [gettingstarted_shard2_replica_n4] webapp=/solr path=/select params={df=_text_&distrib=false&fl=id&fl=score&shards.purpose=4&start=0&fsv=true&shard.url=http://127.0.1.1:7574/solr/gettingstarted_shard2_replica_n4/|http://127.0.1.1:8983/solr/gettingstarted_shard2_replica_n6/&rows=10&version=2&q=test&NOW=1512474627254&isShard=true&wt=javabin} hits=0 status=0 QTime=0 2) [gettingstarted_shard1_replica_n1] webapp=/solr path=/select params={q=test&indent=on&wt=json} hits=0 status=0 QTime=13 ############################################################################################################################## ############################################################################################################################## Sample4 (q=baa): http://localhost:8983/solr/gettingstarted/select?indent=on&q=baa&wt=json produced logs: 1) [gettingstarted_shard2_replica_n4] webapp=/solr path=/select params={df=_text_&distrib=false&fl=id&fl=score&shards.purpose=4&start=0&fsv=true&shard.url=http://127.0.1.1:7574/solr/gettingstarted_shard2_replica_n4/|http://127.0.1.1:8983/solr/gettingstarted_shard2_replica_n6/&rows=10&version=2&q=baa&NOW=1512474709460&isShard=true&wt=javabin} hits=0 status=0 QTime=0 http://localhost:7574/solr/gettingstarted/select?indent=on&q=baa&wt=json produced logs: 1) [gettingstarted_shard1_replica_n1] webapp=/solr path=/select params={q=baa&indent=on&wt=json} hits=0 status=0 QTime=12 Sorry for this messy logs. I'll try to sumarize.... For queries against the node 1, the leading node, i never got those "short logs". just containing what i was querying. Instead i recieve logs containing all these sharding information. Sometimes 2 equivalent ones (see sample 1) and sometimes just one log (sample 2-4). Mentioned that i got different logs for the same query/request (sample1 vs sample3). For queries against the node 2, not leading anything, i got those "short logs" everytime. In addition to that, i also recievie sometimes an additional log, containing these sharding information (sample 3). My assumptions: afaik, the queried shard is choosen randomly, that would explain why i got different amount of logs for same queries/request. But what i everytime the same, is that the "non-leading node" is the only one that returns the logs i want. I tried some other example (that i do not write down here), and i saw the same result. different amount of logs, that look spreaded randomly, but i never got those "short-logs" from the leading node, just from the "non-leading node". So the idea of trying to find the difference between logs is not that suitable, because sometimes they aren't present (facing the leading node). So the question still reminds: how could i log the incoming request in a proper way? I hope that my problem was clearly described, and someone got an idea whats going on here.