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Hadoop >> mail # user >> Group mismatches?


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Re: Group mismatches?
In all places I have found it only to be the primary group, not all
the users supplemental groups.

On Mon, Jul 16, 2012 at 3:05 PM, Clay B. <[EMAIL PROTECTED]> wrote:
> Hi all,
>
> I have a Hadoop cluster which uses Samba to map an Active Directory domain
> to my CentOS 5.7 Hadoop cluster. However, I notice a strange mismatch with
> groups. Does anyone have any debugging advice, or how to refresh the DFS
> groups mapping? If not, should I file a bug at
> https://issues.apache.org/jira/browse/HADOOP?
>
> # I see the following error:
> [clayb@hamster ~]$ hadoop fs -ls /projects/foobarcommander
> log4j:ERROR Could not find value for key log4j.appender.NullAppender
> log4j:ERROR Could not instantiate appender named "NullAppender".
> ls: could not get get listing for
> 'hdfs://hamster:9000/projects/foobarcommander' :
> org.apache.hadoop.security.AccessControlException: Permission denied:
> user=clayb, access=READ_EXECUTE,
> inode="/projects/foobarcommander":hadmin:foobarcommander:drwxrwx---
>
> # I verify group membership -- look a mismatch!
> [clayb@hamster ~]$ which groups
> /usr/bin/groups
> [clayb@hamster ~]$ groups
> foobarcommander xxx_rec_eng domain users all all_north america batchlogon
> xxx-s xxx03-s xxx1-admins xxx-emr-users xxx-emr-admins xxx1-users
> BUILTIN\users
> [clayb@hamster ~]$ hadoop dfsgroups
> log4j:ERROR Could not find value for key log4j.appender.NullAppender
> log4j:ERROR Could not instantiate appender named "NullAppender".
> clayb : domain users xxx_rec_eng xxx-emr-users all xxx-emr-admins batchlogon
> all_north america xxx1-users xxx-s xxx03-s xxx1-admins BUILTIN\users
>
> Notice, in particular the foobarcommander group is only shown for my
> /usr/bin/groups output. It looks like the following from the HDFS
> Permissions Guide[1] is not correct, in my case:
> "The group list is the equivalent of `bash -c groups`."
>
> # I have tried the following to no useful effect:
> [admin@hamster ~]$ hadoop dfsadmin -refreshUserToGroupsMappings
> log4j:ERROR Could not find value for key log4j.appender.NullAppender
> log4j:ERROR Could not instantiate appender named "NullAppender".
>
> # I do, however, see other users with the foobarcommander group, so the
> group should be "visible" to Hadoop:
> [clayb@hamster ~]$ hadoop dfsgroups pat
> log4j:ERROR Could not find value for key log4j.appender.NullAppender
> log4j:ERROR Could not instantiate appender named "NullAppender".
> pat : domain users all_north america all_san diego all foobarcommander
> BUILTIN\users
> # And 'hadoop mrgroups' (like dfsgroups) returns the same bad data, for me:
> [clayb@hamster ~]$ hadoop mrgroups
> log4j:ERROR Could not find value for key log4j.appender.NullAppender
> log4j:ERROR Could not instantiate appender named "NullAppender".
> clayb : domain users xxx_rec_eng xxx-emr-users all xxx-emr-admins batchlogon
> all_north america xxx1-users xxx-s xxx03-s xxx1-admins BUILTIN\users
>
> # And I see that the system is getting the right data via getent(1):
> [clayb@hamster ~]$ getent group foobarcommander
> foobarcommander:*:16777316:pat,user1,user2,user3,clayb,user4,user5,user6,user7,user8,user9,user10,user12,user13,user14,user15
>
> # I am using Cloudera's CDH3u4 Hadoop:
> [clayb@hamster ~]$ hadoop version
> Hadoop 0.20.2-cdh3u4
> Subversion file:///data/1/tmp/topdir/BUILD/hadoop-0.20.2-cdh3u4 -r
> 214dd731e3bdb687cb55988d3f47dd9e248c5690
> Compiled by root on Mon May  7 14:03:02 PDT 2012
> From source with checksum a60c9795e41a3248b212344fb131c12c
>
> I also do not see any obviously useful errors in my namenode logs.
>
> -Clay
>
> [1]:
> http://hadoop.apache.org/common/docs/r0.20.2/hdfs_permissions_guide.html#User+Identity
>