Specifications

Always Propagate Permissions
Inheritance is a powerful feature, so take advantage of it. By propagating permissions
down a folder hierarchy, you save yourself the time and eort required to manually
assign permissions to descendants.
Use the Eective Permission Inspector
Frequently use the Eective Permission Inspector to make sure users have the correct
access to important resources. This is especially important after changing ACLs.
Sometimes, you might inadvertently give someone more or fewer permissions than
needed. The inspector helps you detect these cases.
For more information about the inspector, see “Determining a Users File or Folder
Permissions” on page 56.
Protect Applications from Being Modied
If you are sharing applications, make sure you set permissions for applications so that
no one, except a trusted few, can change them. This is a vulnerability that attackers can
exploit to introduce viruses or Trojan horses in your environment.
Keep It Simple
You can unnecessarily complicate le access management if you’re not careful. Keep it
simple. If standard POSIX permissions do the job, use those, but if you must use ACLs,
avoid customizing permissions unless you need to.
Also, use simple folder hierarchies when feasible. A little strategic planning can help
you create eective and manageable shared hierarchies.
Common Folder Congurations
When sharing les and folders between computers, you can set custom permissions
to grant or restrict access to those les and folders.
Before you begin setting custom le and folder permissions, you might want to
investigate how the le and folder will be shared, who has access, and what type
of access you want users to have. A recommended way to manage le and folder
permissions is to create groups of users who share the same privileges.
Depending on your network environment you can use either POSIX, ACL, or both
to manage le or folder access.
The following table shows examples of the POSIX permissions and the ACL
permissions necessary to congure some common folder sharing settings.
28 Chapter 2 Setting Up File Service Permissions