Presently basically send the next remove-by-query command to Solr, the index ought to be removed of records:

//<delete><query>*:*</query></delete>
http://<solr-server>:<port>/solr/update?stream.body=%3Cdelete%3E%3Cquery%3E*%3A*%3C%2Fquery%3E%3C%2Fdelete%3E

The response I achieve with a home solr server appears normal:

<response>
  <lst name="responseHeader">
    <int name="status">0</int>
    <int name="QTime">13</int>
  </lst>
</response>

However, basically restart Solr by restarting Tomcat, then execute a choose query, I still retrieve indexed search engine results. How come these results not erased?

(Note: on my small laptop I installed a Solr instance, which process works fine when removing the index)

Following the remove you have to send a commit query too:

http://<solr-server>:<port>/solr/update?stream.body=<commit/>

I discovered afterwards the remove-by-query instructions were failing because file permissions on our linux server were stopping Solr from carrying out the updates. Utilizing a chmod command fixed this.

Any recommendations for security on this is appreciated.