Clicking through to one of them yields the following exception message:
Zookeeper did not start within 20 seconds. Check the logs in /var/lib/jenkins/workspace/apache-accumulo-1.6/minicluster/target/mini-tests/org.apache.accumulo.minicluster.MiniAccumuloClusterTest/logs for errors. Last exception: java.net.ConnectException: Connection refused
Going to that directory, I find an empty ZooKeeperServerMain_1480462011.err and a single line in the .out file:
Listening for transport dt_socket at address: 33078
The port changes between runs, but I'm fairly sure that is expected. However, looking at conf/zoo.cfg I see:
#Wed Mar 26 05:38:18 PDT 2014
So for some reason the ports don't match up.