[SOLR-2369] Zookeeper depends on log4j, thus also SolrCloud does

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.1
• Component/s: SolrCloud
• Labels: log4j slf4j zookeeper
• Assignee: Yonik Seeley
• Reporter: Jan Høydahl
• Created: 16/Feb/11 22:18
• Updated: 04/Oct/11 16:31
• Resolved: 17/Feb/11 23:10

Description

Reproduce:
1. Use default Solr example build (with JDK logging)
2. Run example C on http://wiki.apache.org/solr/SolrCloud
3. You get Exception:
java.lang.NoClassDefFoundError: org/apache/log4j/jmx/HierarchyDynamicMBean
at org.apache.zookeeper.jmx.ManagedUtil.registerLog4jMBeans(ManagedUtil.java:51)
at org.apache.zookeeper.server.quorum.QuorumPeerMain.runFromConfig(QuorumPeerMain.java:114)
at org.apache.solr.cloud.SolrZkServer$1.run(SolrZkServer.java:111)

Probable reason:
Zookeeper depends on log4j

Quickfix:
Switch to log4j logging (as you cannot include both log4j bridge and log4j):

• Remove log4j-over-slf4j-1.5.5.jar and slf4j-jdk14-1.5.5.jar
• Add slf4j-logj12.jar and log4j-1.2.16.jar

Document the shortcoming in release notes

Long term fix:
Vote for the resolution of ZOOKEEPER-850 which switches ZK to slf4j logging

Issue Links

• is blocked by: ZOOKEEPER-850 Switch from log4j to slf4j