Not able to give write permission to Folder



I am not able to execute below scripts for Flume lab:

[85mesanta8172@cxln4 ~]$ sudo chmod a+w -R /flume
We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:
#1) Respect the privacy of others.
#2) Think before you type.
#3) With great power comes great responsibility.
[sudo] password for 85mesanta8172:
Sorry, user 85mesanta8172 is not allowed to execute ‘/bin/chmod a+w -R /flume’ as root on cxln4.

[85mesanta8172@cxln4 ~]$ hdfs dfs -mkdir -p /flume/weblogs
mkdir: Permission denied: user=85mesanta8172, access=WRITE, inode="/flume/weblogs":hdfs:hdfs:drwxr-xr-x


You don’t have any permission to create/change files at level “/”. Only your home directory is writable by you.