chmod 770 /data
Verify using : ls -ld /data Preview should be like:
drwxrwx--- 2 root sysadmin 4096 Mar 16 18:08 /data
To change the permission on directory we use the chmod command.
According to the question that only the owner user (root) and group member (sysadmin) can fully access the directory so: chmod 770 /data