diff --git a/htroot/IndexControlURLs_p.html b/htroot/IndexControlURLs_p.html
index 8dc15f2c9..c22c46516 100644
--- a/htroot/IndexControlURLs_p.html
+++ b/htroot/IndexControlURLs_p.html
@@ -161,6 +161,15 @@ function updatepage(str) {
         </dd>
       </dl>
     </fieldset>
+    </form>
+    <form action="IndexControlURLs_p.html" method="post" enctype="multipart/form-data" accept-charset="UTF-8">
+    <fieldset><legend>Reboot Solr Core</legend>
+      <dl>
+        <dt class="TableCellLight">&nbsp;</dt>
+        <dd><input type="submit" name="rebootsolr" value="Shut Down and Re-Start Solr" class="submitready" style="width:240px;"/>
+        </dd>
+      </dl>
+    </fieldset>
     </form>::
     #(/dumprestore)#
     
diff --git a/htroot/IndexControlURLs_p.java b/htroot/IndexControlURLs_p.java
index 6d3fe2e59..69f43c97a 100644
--- a/htroot/IndexControlURLs_p.java
+++ b/htroot/IndexControlURLs_p.java
@@ -270,6 +270,7 @@ public class IndexControlURLs_p {
             final File dump = segment.fulltext().dumpSolr();
             prop.put("indexdump", 1);
             prop.put("indexdump_dumpfile", dump.getAbsolutePath());
+            sb.tables.recordAPICall(post, "IndexControlURLs_p.html", WorkTables.TABLE_API_TYPE_STEERING, "solr dump generation");
         }
 
         if (post.containsKey("indexrestore")) {
@@ -277,6 +278,11 @@ public class IndexControlURLs_p {
             segment.fulltext().restoreSolr(dump);
         }
 
+        if (post.containsKey("rebootsolr")) {
+            segment.fulltext().rebootSolr();
+            sb.tables.recordAPICall(post, "IndexControlURLs_p.html", WorkTables.TABLE_API_TYPE_STEERING, "solr reboot");
+        }
+
         if (post.containsKey("deletedomain")) {
             final String domain = post.get("domain");
             segment.fulltext().deleteDomainHostname(domain, null);
diff --git a/source/net/yacy/search/index/Fulltext.java b/source/net/yacy/search/index/Fulltext.java
index 54c5d8694..3e61c6975 100644
--- a/source/net/yacy/search/index/Fulltext.java
+++ b/source/net/yacy/search/index/Fulltext.java
@@ -221,11 +221,15 @@ public final class Fulltext {
     }
     
     public SolrConnector getDefaultConnector() {
-        return this.solrInstances.getDefaultMirrorConnector();
+        synchronized (this.solrInstances) {
+            return this.solrInstances.getDefaultMirrorConnector();
+        }
     }
     
     public SolrConnector getWebgraphConnector() {
-        return this.solrInstances.getMirrorConnector(WebgraphSchema.CORE_NAME);
+        synchronized (this.solrInstances) {
+            return this.solrInstances.getMirrorConnector(WebgraphSchema.CORE_NAME);
+        }
     }
 
     public void clearCache() {
@@ -247,20 +251,24 @@ public final class Fulltext {
     }
 
     public void clearLocalSolr() throws IOException {
-        EmbeddedInstance instance = this.solrInstances.getSolr0();
-        if (instance != null) {
-            for (String name: instance.getCoreNames()) new EmbeddedSolrConnector(instance, name).clear();
+        synchronized (this.solrInstances) {
+            EmbeddedInstance instance = this.solrInstances.getSolr0();
+            if (instance != null) {
+                for (String name: instance.getCoreNames()) new EmbeddedSolrConnector(instance, name).clear();
+            }
+            this.commit(false);
+            this.solrInstances.clearCache();
         }
-        this.commit(false);
-        this.solrInstances.clearCache();
     }
 
     public void clearRemoteSolr() throws IOException {
-        ShardInstance instance = this.solrInstances.getSolr1();
-        if (instance != null) {
-            for (String name: instance.getCoreNames()) new RemoteSolrConnector(instance, name).clear();
+        synchronized (this.solrInstances) {
+            ShardInstance instance = this.solrInstances.getSolr1();
+            if (instance != null) {
+                for (String name: instance.getCoreNames()) new RemoteSolrConnector(instance, name).clear();
+            }
+            this.solrInstances.clearCache();
         }
-        this.solrInstances.clearCache();
     }
 
     /**
@@ -822,6 +830,22 @@ public final class Fulltext {
         }
     }
     
+    /**
+     * reboot solr (experimental to check resource management
+     */
+    public void rebootSolr() {
+        synchronized (this.solrInstances) {
+            this.disconnectLocalSolr();
+            this.solrInstances.close();
+            this.solrInstances = new InstanceMirror();
+            try {
+                this.connectLocalSolr();
+            } catch (IOException e) {
+                Log.logException(e);
+            }
+        }
+    }
+    
     // export methods
     public Export export(final File f, final String filter, final int format, final boolean dom) {
         if ((this.exportthread != null) && (this.exportthread.isAlive())) {