Hello @Jonas Straub, sorry for reopening this old topic, but I'm getting the same error. In my case, cluster is kerberized. I'm using HDP 2.6.0.3 with Ambari 2.5.0.3 and Solr 5.5 installed via Mpack. Solr authentication via SPNEGO is working fine, but when I tried to enable the ranger plugin for solr I'm getting a strange behavior, because if I configure log4j for INFO I'm getting 403 error (but ranger policies are well configured and I can see the ranger cache updated locally on the solr node), while if I set log4j to log DEBUG information I'm getting a 500 error from solr server. Looking at the source code of solr and ranger-solr it seems that ranger plugin is unable to obtain the AuthorizationContext, in fact I can see these lines in the log: 2018-05-22 13:03:17,703 [qtp537548559-18 - /solr/] DEBUG [ ] org.apache.solr.servlet.HttpSolrCall (HttpSolrCall.java:316) - no handler or core retrieved for /, follow through... 2018-05-22 13:03:17,703 [qtp537548559-18 - /solr/] DEBUG [ ] org.apache.solr.servlet.HttpSolrCall (HttpSolrCall.java:499) - PkiAuthenticationPlugin says authorization required : true 2018-05-22 13:03:17,704 [qtp537548559-18 - /solr/] DEBUG [ ] org.apache.solr.servlet.HttpSolrCall (HttpSolrCall.java:421) - AuthorizationContext : [FAILED toString()] .... 2018-05-22 13:03:17,717 [qtp537548559-18 - /solr/] ERROR [ ] org.apache.ranger.authorization.solr.authorizer.RangerSolrAuthorizer (RangerSolrAuthorizer.java:288) - Error getting request context!!! java.lang.NullPointerException at org.apache.solr.servlet.HttpSolrCall$2.getParams(HttpSolrCall.java:953) at org.apache.ranger.authorization.solr.authorizer.RangerSolrAuthorizer.logAuthorizationConext(RangerSolrAuthorizer.java:279) at org.apache.ranger.authorization.solr.authorizer.RangerSolrAuthorizer.authorize(RangerSolrAuthorizer.java:165) at org.apache.ranger.authorization.solr.authorizer.RangerSolrAuthorizer.authorize(RangerSolrAuthorizer.java:128) at org.apache.solr.servlet.HttpSolrCall.call(HttpSolrCall.java:422) Since this version of Ambari does not support the ranger solr plugin, I had to manually edit the setup_solr_kerberos_auth.py script, adding "authorization":{"class":"org.apache.ranger.authorization.solr.authorizer.RangerSolrAuthorizer"}, so my current security.json file on zookeeper is the following: {"authentication":{"class": "org.apache.solr.security.KerberosPlugin"},"authorization":{"class":"org.apache.ranger.authorization.solr.authorizer.RangerSolrAuthorizer"}} apart of that, I followed the instructions provided here and the repo on ranger is working. Is it a missing configuration or maybe a bug? Exact versions I using are the following: ranger-solr-plugin-0.7.0.2.6.0.3-8.el6.noarch ranger_2_6_0_3_8-solr-plugin-0.7.0.2.6.0.3-8.x86_64 lucidworks-hdpsearch-2.6-100.noarch Thanks, Davide ... View more