/Var issues check :

ls -lh /var/log/* >> check for the log files which is consuming high size


 ls -hrSal /var/spool/mail/*  >> Check for the account usernames which is consuming high size (above 50 MB) then,

tail -2000 /var/spool/mail/username


ls -lh /var/spool/mqueue/*  >> check the recent email headers using the command :

tail -2000 /var/spool/mqueue/id