How to fix Solr Exception: Could not find necessary SLF4j logging jars?

Question

I have big problems installing Solr 4.3 under Ubuntu 12.04. Firstly i installed tomcat. I can access tomcat via browser on localhost:8080. Into "Tomcat Web Application Manager" i try to install Solr 4.3 via 2solr.war" file. The file is been uploaded an deployed. But i cant get it started. "FAIL - Application at context path /solr could not be started".

The log file (localhost.log) look like:

07.05.2013 11:05:36 org.apache.catalina.core.ApplicationContext log
INFO: HTMLManager: start: Starting web application at '/solr'
07.05.2013 11:05:36 org.apache.catalina.core.StandardContext filterStart
SCHWERWIEGEND: Exception starting filter SolrRequestFilter
org.apache.solr.common.SolrException: Could not find necessary SLF4j logging jars. If using Jetty, the SLF4j logging jars need to go in the jetty lib/ext directory. For other containers, the corresponding directory should be used. For more information, see: http://wiki.apache.org/solr/SolrLogging
    at org.apache.solr.servlet.SolrDispatchFilter.<init>(SolrDispatchFilter.java:105)
    ... 33 more
07.05.2013 11:05:36 org.apache.catalina.core.ApplicationContext log
INFO: HTMLManager: list: Listing contexts for virtual host 'localhost'
07.05.2013 11:05:36 org.apache.catalina.core.StandardContext filterStart
SCHWERWIEGEND: Exception starting filter SolrRequestFilter
org.apache.solr.common.SolrException: Could not find necessary SLF4j logging jars. If using Jetty, the SLF4j logging jars need to go in the jetty lib/ext directory. For other containers, the corresponding directory should be used. For more information, see: http://wiki.apache.org/solr/SolrLogging
    at org.apache.solr.servlet.SolrDispatchFilter.<init>(SolrDispatchFilter.java:105)
    ... 21 more

catalina.....log

07.05.2013 11:05:36 org.apache.catalina.core.StandardContext start
SCHWERWIEGEND: Error filterStart
07.05.2013 11:05:36 org.apache.catalina.core.StandardContext start
SCHWERWIEGEND: Context [/solr] startup failed due to previous errors
07.05.2013 11:05:36 org.apache.catalina.startup.HostConfig checkResources
INFO: Reloading context [/solr]
07.05.2013 11:05:36 org.apache.catalina.core.StandardContext stop
INFO: Container org.apache.catalina.core.ContainerBase.[Catalina].[localhost].[/solr] has not been started
07.05.2013 11:05:36 org.apache.catalina.core.StandardContext start
SCHWERWIEGEND: Error filterStart
07.05.2013 11:05:36 org.apache.catalina.core.StandardContext start
SCHWERWIEGEND: Context [/solr] startup failed due to previous errors

Can somebody help me and tell me what to do?

Answer 1

As the logs say - Could not find necessary SLF4j logging jars.

You are missing the slf4j jars.

Place the slf4j jars in the $CATALINA_BASE/lib folder. For more information have a look here