Datasheet

“main” (Installation and Administration) — 2004/6/25 — 13:29 — page 560 — #586
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23.2.7 Data Volume and Hard Disk Requirements
A sufficient amount of free space for all distributed data is required on the
hard disks of all involved hosts. subversion or CVS require additional
space for the repository database on the server. The file history is also
stored on the server, requiring even more space. When files in text for-
mat are changed, only the modified lines need to be saved. Binary files re-
quire additional space amounting to the size of the file every time the file is
changed.
23.2.8 GUI
Unison offers a graphical user interface that displays the synchronization
procedures Unison wants to perform. Accept the proposal or exclude indi-
vidual files from the synchronization. In text mode, interactively confirm
the individual procedures.
Experienced users normally run subversion or CVS from the command
line. However, graphical user interfaces are available for Linux, such as
cervisia, and for other operating systems, like wincvs. Many development
tools (such as kdevelop) and text editors (such as emacs) provide support
for CVS or subversion. The resolution of conflicts is often much easier to
perform with these front-ends.
23.2.9 User Friendliness
Unison and rsync are rather easy to use and are also suitable for newcom-
ers. CVS and subversion are somewhat more difficult to operate. Users
should understand the interaction between the repository and local data.
Changes to the data should first be merged locally with the repository.
This is done with the command cvs update or svn update. Then the
data must be sent back to the repository with the command cvs commit
or svn commit. Once this procedure has been understood, newcomers are
also able to use CVS or subversion with ease.
23.2.10 Security against Attacks
During transmission, the data should ideally be protected against intercep-
tion and manipulation.
Unison, CVS, rsync, and subversion can easily be used via ssh (secure
shell), providing security against attacks of this kind. Running CVS or
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23.2. Determining Factors for Selecting a Program