Adding/Removing Storage - Red Hat ENTERPRISE LINUX 3 - INTRODUCTION TO SYSTEM ADMINISTRATION Administration Manual

Chapter 5. Managing Storage
There is a problem with the first approach — depending on how access is granted, user #2 may have
full access to all of user #1's files. Worse, it might have been done in such a way as to permit all users
in your organization access to user #1's files. Still worse, this change may not be reversed after user
#2 no longer requires access, leaving user #1's files permanently accessible by others. Unfortunately,
when users are in charge of this type of situation, security is rarely their highest priority.
The second approach eliminates the problem of making all of user #1's files accessible to others. How-
ever, once the file is in the file exchange area the file is readable (and depending on the permissions,
even writable) by all other users. This approach also raises the possibility of the file exchange area
becoming filled with files, as users often forget to clean up after themselves.
The third approach, while seemingly an awkward solution, may actually be the preferable one in most
cases. With the advent of industry-standard email attachment protocols and more intelligent email
programs, sending all kinds of files via email is a mostly foolproof operation, requiring no system
administrator involvement. Of course, there is the chance that a user will attempt to email a 1GB
database file to all 150 people in the finance department, so some amount of user education (and
possibly limitations on email attachment size) would be prudent. Still, none of these approaches deal
with the situation of two or more users needing ongoing access to a single file. In these cases, other
methods are required.
5.7.3.2. File Sharing
When multiple users need to share a single copy of a file, allowing access by making changes to file
permissions is not the best approach. It is far preferable to formalize the file's shared status. There are
several reasons for this:
Files shared out of a user's directory are vulnerable to disappearing unexpectedly when the user
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either leaves the organization or does nothing more unusual than rearranging their files.
Maintaining shared access for more than one or two additional users becomes difficult, leading to
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the longer-term problem of unnecessary work required whenever the sharing users change respon-
sibilities.
Therefore, the preferred approach is to:
Have the original user relinquish direct ownership of the file
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Create a group that will own the file
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Place the file in a shared directory that is owned by the group
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Make all users needing access to the file part of the group
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Of course, this approach would work equally well with multiple files as it would with single files, and
can be used to implement shared storage for large, complex projects.

5.7.4. Adding/Removing Storage

Because the need for additional disk space is never-ending, a system administrator often needs to add
disk space, while sometimes also removing older, smaller drives. This section provides an overview
of the basic process of adding and removing storage.
Note
On many operating systems, mass storage devices are named according to their physical connection
to the system. Therefore, adding or removing mass storage devices can result in unexpected changes
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