Scenario: You upgrade from Solr 1.3 to 1.4 and receive a local host error
After you upgrade from version 1.3 to 1.4 and navigate to the local host (http://localhost:8080/solr), you receive the following error:
org.apache.solr.common.SolrException: Error loading class 'solr.FastLRUCache' at
org.apache.solr.core.SolrResourceLoader.findClass(SolrResourceLoader.java:273) at org.apache.solr.search.CacheConfig.getConfig
or similar error.
Answer: Undeploy Solr
This error typically occurs because there was a mismatch between Solr 1.3 and Solr 1.4 files when you tried to upgrade. For this reason, we recommend that you undeploy Solr 1.3 before upgrading to Solr 1.4.
To undeploy Solr:
- Open the Tomcat main page at http://servername:8080.
- Click Administration > Tomcat Manager.
- Locate /solr in the Applications table.
- Click the Undeploy link, which is located in the farthest-left column.
- Answer the confirmation dialog box.
Solr is now undeployed. All traces of Solr prior to undeploying it in Tomcat manager are removed.
The undeploy action will work even if all files were already removed.