问题
I have set the replication factor for my file as follows:
hadoop fs -D dfs.replication=5 -copyFromLocal file.txt /user/xxxx
When a NameNode restarts, it makes sure under-replicated blocks are replicated.
Hence the replication info for the file is stored (possibly in nameNode). How can I get that information?
回答1:
Try to use command hadoop fs -stat %r /path/to/file, it should print the replication factor.
回答2:
You can run following command to get replication factor,
hadoop fs -ls /user/xxxx
The second column in the output signify replication factor for the file and for the folder it shows -, as shown in below pic.
回答3:
Apart from Alexey Shestakov's answer, which works perfectly and does exactly what you ask, other ways, mostly found here, include:
hadoop dfs -ls /parent/path
which shows the replication factors of all the /parent/path contents on the second column.
Through Java, you can get this information by using:
FileStatus.getReplication()
You can also see the replication factors of files by using:
hadoop fsck /filename -files -blocks -racks
Finally, from the web UI of the namenode, I believe that this information is also available (didn't check that).
回答4:
We can use following commands to check replication of the file.
hdfs dfs -ls /user/cloudera/input.txt
or
hdfs dfs -stat %r /user/cloudera/input.txt
来源：https://stackoverflow.com/questions/25166926/how-do-you-retrieve-the-replication-factor-info-in-hdfs-files