Given a directory DirA (directory owner is root and group is sys).Given a user userA, user belongs to group sys, he should be able to make a sub directory inside DirA ?on Solaris SunOS 5.9 I have a directory /opt:  bash-2.05$ ls -la /total 1205drwxr-xr-x  34 root     root        1024 Mar 17 04:21 .drwxr-xr-x  34 root     root        1024 Mar 17 04:21 .... Removed all..lrwxrwxrwx   1 root     other         16 Apr 14  2008 opt -> /export/home/optThis symbolic link takes me to:  bash-2.05$ ls -la /export/hometotal 524638drwxr-xr-x  31 root     root        1024 Jan 25  2015 .drwxr-xr-x   3 root     sys          512 Jul  2  2007 .....REMOVED...drwxr-xr-x  12 root     sys          512 Apr 24 10:29 optI am logged in with user builder:  bash-2.05$ /usr/ucb/whoamibuilderAnd he belongs to groups:  bash-2.05$ groups builderother root sys bash-2.05$So why mkdir fails in /opt/?bash-2.05$ cd /opt/bash-2.05$ pwd/optbash-2.05$ mkdir mynewdirmkdir: Failed to make directory mynewdir; Permission deniedbash-2.05$ cd /export/home/opt/bash-2.05$ mkdir mynewdirmkdir: Failed to make directory mynewdir; Permission deniedbash-2.05$
No permission to create sub directory when user belongs to directory group
filesystems;directory;solaris
drwxr-xr-x  12 root     sys          512 Apr 24 10:29 optmeans that the directory is only writable for root. For sys group members to be able to make changes to the directory (including creating subdirectories), it needs to bedrwxrwxr-x  12 root     sys          512 Apr 24 10:29 optIf you want to enable this:chmod g+w optwill make the appropriate change.