hi all,

    i want to control the hdfs's security,what should i do,i know the kerberos is supported by hadoop 1.0.0
in our's hadoop ,we have 8 user group ,and more than 40 user.every user has their hdfs file authority and mapreduce conf.
Is there any third part jars ,can easily change user's authority.do i need to develop this applications？

thanks
jeff