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When to Run a
News Server
News servers tend to be used in three ways: Usenet news The global network of news servers is known as Usenet. When a server participates in Usenet news, it
exchanges one or more newsgroups (named
discussion forums) with other news servers, resulting in the worldwide message
system described earlier. Most Internet Service Providers (ISPs) and
universities run Usenet news servers, as do some companies. Internal
communications An organization may set up a
news server to facilitate communications among members of the organization, or
associated individuals. For instance, employees working on a single project or
students in a class might use a news server to communicate amongst themselves. Similarly,
some companies run news servers that host discussions of the companies'
products for the benefit of customers. Offline news reading As noted earlier, offline news reading allows an individual or
small group to read news without tying up a network connection while doing so. This
is often desirable in homes with just one phone line or when telephone
connection costs are billed by the minute. Such a use involves the transfer of
only a few Usenet news groups.Both full Usenet news and internal news use
the same software. The main theoretical difference between the connected and
isolated systems is one of the external connection or lack thereof. In
practice, there's another major difference: A full Usenet news server (one that
hosts more than a trivial fraction of the thousands of available newsgroups)
consumes a great deal of disk space and network bandwidth in exchanging the
news messages. A system that hosts a full Usenet news server is likely to
require so much disk space and bandwidth that it won't be useful for much of
anything else. Such a system will need a hard disk that's tens or even hundreds
of gigabytes in size just for the news articles. Of course, a system with much
more limited newsgroup availability, such as a personal system intended for
offline news reading, won't have such huge resource requirements.WARNING
align=left border=0> News servers typically place their news
articles in the /var/spool/news directory tree. If you didn't install Linux with a news server in
mind, this directory may reside on the root partition, or possibly on a
smallish /var partition. A dedicated news server generally uses a huge /var or /var/spool/news partition to hold the news posts. You should be sure the computer
you intend to use for this purpose has adequate disk space in /var/spool/news , or possibly change the spool directory to some other partition
where you do have adequate space.
TIP
align=left border=0> Using a journaling filesystem, such as
ReiserFS or XFS, can greatly reduce startup times after a system crash or
power outage, particularly for a system like a news server that has a large
hard disk. Keeping the news spool directory on its own dedicated partition
can enhance system stability, because a filesystem error involving the spool
directory (which is transient in nature) need not affect system stability.
Because of the need for dedicating an entire
computer and bandwidth that's measured in megabits per second to a full Usenet
news server, it's unlikely that a small office or home will need such a server.
Instead, such users are better served by using their ISPs' news server or a
third-party news server. (Some popular commercial news providers include
Giganews, http://www.giganews.com ; Supernews, target="_blank">http://www.supernews.com ; and NewsGuy, target="_blank">http://www.newsguy.com . You can find a list of free third-party news servers at
http://groups.google.com archive site holds archives of many popular newsgroups, accessible through a Web-based
interface.) The discussion of regular news servers in this chapter (in the
section "
focuses on the internal communications use of a news server, although it
doesn't completely ignore the data transfer configuration required of a regular
Usenet news server.Offline news reading is often done through a
feature of news readers (news client programs), but it can be done through a
special limited-function news server, such as the Leafnode program described in
the "
section of this chapter. Such programs have different configuration requirements
than do conventional news servers, but they work much the same from the
client's point of view. If you have a full-time connection to the Internet (via
a corporate LAN or home broadband account), chances are you'll find it easier
to use your ISP's news server directly rather than use an intermediate news
server. You might use such an option when your Internet connection is limited
or costly, or if your ISP's news server is overloaded when you want to use
ityou can configure Leafnode to transfer messages during off hours, thus
making your news reading quicker. You might also want to use Leafnode if your
system serves one or two dozen people who read largely the same newsgroups,
because in such a scenario, running your own server can reduce your external
news-related data traffic.
