What is the design of Snapshots in HDFS? This PDF documents the design of snapshot. Jing Zhao and Tsz-Wo Sze from Hortonworks gave a great talk on the design of HDFS snapshots. The slides can be downloaded at here. The development of snapshot is tracked by HDFS-2802. Read more: How to set the replication factor for one file when it is uploaded by `hdfs dfs -put` command line in HDFS? How to estimate the memory usage of HDFS NameNode for a HDFS cluster? HDFS stays in safe mode because of reported blocks not reaching 0.9990 of total blocks How to set replication factors for HDFS directories? How to manually kill HDFS DataNodes? How to put files with spaces in names into HDFS? How to find out all files with replication factor 1 in HDFS? How to force a checkpointing of metadata in HDFS?