This test failed on a recent jenkins run with the following:
org.junit.ComparisonFailure: expected:<[Could not obtain the last block locations.]> but was:<[Zero blocklocations for /home/jenkins/jenkins-slave/workspace/PreCommit-HDFS-Build/trunk/hadoop-hdfs-project/hadoop-hdfs/target/test/data/dfs/test. Name node is in safe mode.
The reported blocks 0 needs additional 2 blocks to reach the threshold 0.9990 of total blocks 2. Safe mode will be turned off automatically.