Hello,
HDFS default location /user, you can't delete the home directory for
hdfs. If you create a file or directory, it will be created under /user.
For example: hdfs dfs -mkdir <name>
Regards,
ViSolve Hadoop Support
On 10/8/2014 10:44 AM, Tianyin Xu wrote:
The former, I use
#hdfs dfs -ls
and I can see the directory "/user"
(and that's why I cannot use "hdfs dfs -mkdir" to create a new one)
~t
On Tue, Oct 7, 2014 at 9:06 PM, Azuryy Yu <[email protected]
<mailto:[email protected]>> wrote:
To make sure your dfs.namenode.name.dir is by default.
then, how did you find /user exists? hdfs dfs -ls ? or you checked
dfs.datanode.data.dir? if the latter, then don't worry.
On Wed, Oct 8, 2014 at 11:56 AM, Tianyin Xu <[email protected]
<mailto:[email protected]>> wrote:
Hi,
I wanna run some experiments on Hadoop which requires a clean,
initial system state of HDFS for every job execution, i.e.,
the HDFS should be formatted and contain nothing.
I keep /dfs.datanode.data.dir/ and /dfs.namenode.name.dir/ the
default, which are located in /tmp
Every time before running a job,
1. I first delete dfs.datanode.data.dir and dfs.namenode.name.dir
#rm -Rf /tmp/hadoop-tianyin*
2. Then I format the nameNode
#bin/hdfs namenode -format
3. Start HDFS
sbin/start-dfs.sh
4. However, I still find the previous metadata (e.g., the
directory I previously created) in HDFS, for example,
#bin/hdfs dfs -mkdir /user
mkdir: `/user': File exists
Could anyone tell me what I missed or misunderstood? Why I can
still see the old data after both physically delete the
directories and reformat the HDFS nameNode?
Thanks a lot for your help!
Tianyin
--
Tianyin XU,
http://cseweb.ucsd.edu/~tixu/ <http://cseweb.ucsd.edu/%7Etixu/>
