Hey,
Because HBase is a database, it opens many files at the same time. The default setting of 1024 for the maximum number of open files on most Unix-like systems is insufficient. Any significant amount of loading will result in failures and cause error messages such as
java.io.IOException...
Be logged in the HBase or HDFS log files. You may also notice errors such as:
Exception increateBlockOutputStream java.io.EOFException
Abandoning block blk_-6935524980745310745_1391901