[Hadoop-common-user] Namenode Safe Mode?

I think it's in safe mode for a short time after startup to check the
integrity of the file system.

Hi

It has been in safe mode all time. I am not bale to execute jobs too. I find
some error sayin canot delete file. Namenode is in safemode.

Thanks,
Preethi.C


Ned Rockson wrote:

bin/hadoop dfs -safemode leave

or close to that (check the syntax) has gotten me out of this state in the
past





cpreethi
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hadoop-user@lucene.apache.org
10/16/2007 11:17 cc
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Subject
Re: Namenode Safe Mode?
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Hi

It has been in safe mode all time. I am not bale to execute jobs too. I
find
some error sayin canot delete file. Namenode is in safemode.

Thanks,
Preethi.C


Ned Rockson wrote:
in

Safe mode is the original state of the NameNode until it has a large
enough collection of DataNodes have reported in to have at least 1
copy of at least X% of the blocks. (The default X is 99.9%). I
recommend changing it to 100%. You can force the NameNode to leave
safe mode manually via "bin/hadoop dfsadmin -safemode leave". In safe
mode, the NameNode lets client do read-only operations but not write
operations (including replication decisions).

-- Owen

Not 1, but dfs.replication.min, which by default is 1.
See also
http://wiki.apache.org/lucene-hadoop/FAQ#12
http://lucene.apache.org/hadoop/api/org/apache/hadoop/dfs/NameNode.html#setSafeMode(org.apache.hadoop.dfs.FSConstants.SafeModeAction)

--Konstantin

Owen O'Malley wrote:

I have found it very helpful to use

hadoop fsck /

In these situations.

If the files that are problematic are not important for you, then you can
exit safe mode explicitly and just delete these files. That will give you a
clean file system.

Examples of files that might be OK to delete include left-over files from
aborted map-reduce jobs or files that you can just re-import into the HDFS
from other storage.