Hi,
Namenode generates new namespaceID every time you format HDFS.
bin#vi /app/hadoop/tmp/dfs/data/current/VERSION
Manually update the namespaceID = 1494801914 to 1580775695, and save the file:
namespaceID=1580775695
storageID=DS-469635027-127.0.0.1-50010-1376974011263
cTime= 1377582559943
storageType=DATA_NODE
layoutVersion=-32