createSnapshot
http://hadoop.apache.org/docs/current/hadoop-project-dist/hadoop-hdfs/HdfsSnapshots.html#Create_Snapshots
deleteSnapshot
http://hadoop.apache.org/docs/current/hadoop-project-dist/hadoop-hdfs/HdfsSnapshots.html#Delete_Snapshots
renameSnapshot
http://hadoop.apache.org/docs/current/hadoop-project-dist/hadoop-hdfs/HdfsSnapshots.html#Rename_Snapshots
HDFS快照
原文：http://www.cnblogs.com/guanx_214/p/5120772.html
