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Next: 14. Permission and Modification Up: rute Previous: 12. Using Internet Services   Contents

Subsections

13. LINUX Resources

Very often it is not even necessary to connect to the Internet to find the information you need. Chapter 16 contains a description of most of the documentation on a LINUX distribution.

It is, however, essential to get the most up-to-date information where security and hardware driver support are concerned. It is also fun and worthwhile to interact with LINUX users from around the globe. The rapid development of Free software could mean that you may miss out on important new features that could streamline IT services. Hence, reviewing web magazines, reading newsgroups, and subscribing to mailing lists are essential parts of a system administrator's role.

13.1 FTP Sites and the sunsite Mirror

The metalab.unc.edu FTP site (previously called sunsite.unc.edu) is one of the traditional sites for free software. It is mirrored in almost every country that has a significant IT infrastructure. If you point your web browser there, you will find a list of mirrors. For faster access, do pick a mirror in your own country.

It is advisable to browse around this FTP site. In particular you should try to find the locations of:

  • The directory where all sources for official GNU packages are stored. This would be a mirror of the Free Software Foundation's FTP archives. These are packages that were commissioned by the FSF and not merely released under the GPL (GNU General Public License). The FSF will distribute them in source form ( .tar.gz) for inclusion into various distributions. They will, of course, compile and work under any UNIX.
  • The generic Linux download directory. It contains innumerable UNIX packages in source and binary form, categorized in a directory tree. For instance, mail clients have their own directory with many mail packages inside. metalab is the place where new developers can host any new software that they have produced. There are instructions on the FTP site to upload software and to request it to be placed into a directory.
  • The kernel sources. This is a mirror of the kernel archives where Linus and other maintainers upload new stable [Meaning that the software is well tested and free of serious bugs.] and beta [Meaning that the software is in its development stages.] kernel versions and kernel patches.
  • The various distributions. RedHat, Debian, and possibly other popular distributions may be present.

This list is by no means exhaustive. Depending on the willingness of the site maintainer, there may be mirrors to far more sites from around the world.

The FTP site is how you will download free software. Often, maintainers will host their software on a web site, but every popular package will almost always have an FTP site where versions are persistently stored. An example is metalab.unc.edu in the directory /pub/Linux/apps/editors/X/cooledit/ where the author's own Cooledit package is distributed.

13.2 HTTP -- Web Sites

Most users should already be familiar with using a web browser. You should also become familiar with the concept of a web search. [Do I need to explain this?]You search the web when you point your web browser to a popular search engine like http://www.google.com/, http://www.google.com/linux, http://infoseek.go.com/, http://www.altavista.com/, or http://www.yahoo.com/ and search for particular key words. Searching is a bit of a black art with the billions of web pages out there. Always consult the search engine's advanced search options to see how you can do more complex searches than just plain word searches.

The web sites in the FAQ (Frequently Asked Questions) (see Appendix D) should all be consulted to get an overview on some of the primary sites of interest to LINUX users.

Especially important is that you keep up with the latest LINUX news. I find the Linux Weekly News <http://lwn.net/> an excellent source. Also, the famous (and infamous) SlashDot <http://slashdot.org/> web site gives daily updates about ``stuff that matters'' (and therefore contains a lot about free software).

Fresh Meat <http://freshmeat.net/> is a web site devoted to new software releases. You will find new or updated packages announced every few hours or so.

Linux Planet <http://www.linuxplanet.com/> seems to be a new (?) web site that I just found while writing this. It looks like it contains lots of tutorial information on LINUX.

News Forge <http://www.newsforge.net/> also contains daily information about software issues.

Lycos <http://download.lycos.com/static/advanced_search.asp> is an efficient FTP search engine for locating packages. It is one of the few search engines that understand regular expressions.

Realistically, though, a new LINUX web site is created every week; almost anything prepended or appended to `` linux'' is probably a web site already.

13.3 SourceForge

A new phenomenon in the free software community is the SourceForge web site, http://www.sourceforge.net/. Developers can use this service at no charge to host their project's web site, FTP archives, and mailing lists. SourceForge has mushroomed so rapidly that it has come to host the better half of all free software projects.

13.4 Mailing Lists

A mailing list is a special address that, when posted to, automatically sends email to a long list of other addresses. You usually subscribe to a mailing list by sending some specially formatted email or by requesting a subscription from the mailing list manager.

Once you have subscribed to a list, any email you post to the list will be sent to every other subscriber, and every other subscriber's posts to the list will be sent to you.

There are mostly three types of mailing lists: the majordomo type, the listserv type, and the *-request type.

13.4.1 Majordomo and Listserv

To subscribe to the majordomo variety, send a mail message to majordomo@<machine> with no subject and a one-line message:

 
subscribe <mailing-list-name>

This command adds your name to the mailing list <mailing-list-name>@<machine>, to which messages are posted.

Do the same for listserv-type lists, by sending the same message to listserv@<machine>.

For instance, if you are an administrator for any machine that is exposed to the Internet, you should get on bugtraq. Send email to

 
subscribe bugtraq

to listserv@netspace.org, and become one of the tens of thousands of users that read and report security problems about LINUX.

To unsubscribe to a list is just as simple. Send an email message:

 
unsubscribe <mailing-list-name>

Never send subscribe or unsubscribe messages to the mailing list itself. Send subscribe or unsubscribe messages only to to the address majordomo@<machine> or listserv@<machine>.

13.4.2 *-request

You subscribe to these mailing lists by sending an empty email message to <mailing-list-name>-request@<machine> with the word subscribe as the subject. The same email with the word unsubscribe removes you from the list.

Once again, never send subscribe or unsubscribe messages to the mailing list itself.

13.5 Newsgroups

A newsgroup is a notice board that everyone in the world can see. There are tens of thousands of newsgroups and each group is unique in the world.

The client software you use to read a newsgroup is called a news reader (or news client). rtin is a popular text mode reader, while netscape is graphical. pan is an excellent graphical news reader that I use.

Newsgroups are named like Internet hosts. One you might be interested in is comp.os.linux.announce. The comp is the broadest subject description for computers; os stands for operating systems; and so on. Many other linux newsgroups are devoted to various LINUX issues.

Newsgroups servers are big hungry beasts. They form a tree-like structure on the Internet. When you send mail to a newsgroup it takes about a day or so for the mail you sent to propagate to every other server in the world. Likewise, you can see a list of all the messages posted to each newsgroup by anyone anywhere.

What's the difference between a newsgroup and a mailing list? The advantage of a newsgroup is that you don't have to download the messages you are not interested in. If you are on a mailing list, you get all the mail sent to the list. With a newsgroup you can look at the message list and retrieve only the messages you are interested in.

Why not just put the mailing list on a web page? If you did, then everyone in the world would have to go over international links to get to the web page. It would load the server in proportion to the number of subscribers. This is exactly what SlashDot is. However, your newsgroup server is local, so you retrieve mail over a faster link and save Internet traffic.

13.6 RFCs

An indispensable source of information for serious administrators or developers is the RFCs. RFC stands for Request For Comments. RFCs are Internet standards written by authorities to define everything about Internet communication. Very often, documentation will refer to RFCs. [There are also a few nonsense RFCs out there. For example there is an RFC to communicate using pigeons, and one to facilitate an infinite number of monkeys trying to write the complete works of Shakespeare. Keep a close eye on Slashdot <http://slashdot.org/> to catch these.]

ftp://metalab.unc.edu/pub/docs/rfc/ (and mirrors) has the complete RFCs archived for download. There are about 2,500 of them. The index file rfc-index.txt is probably where you should start. It has entries like:

 
 
 
 
5 
 
 
 
2045 Multipurpose Internet Mail Extensions (MIME) Part One: Format of
     Internet Message Bodies. N. Freed & N. Borenstein. November 1996.
     (Format: TXT=72932 bytes) (Obsoletes RFC1521, RFC1522, RFC1590)
     (Updated by RFC2184, RFC2231) (Status: DRAFT STANDARD)
 
2046 Multipurpose Internet Mail Extensions (MIME) Part Two: Media
     Types. N. Freed & N. Borenstein. November 1996. (Format: TXT=105854
     bytes) (Obsoletes RFC1521, RFC1522, RFC1590) (Status: DRAFT STANDARD)

and

 
 
 
2068 Hypertext Transfer Protocol -- HTTP/1.1. R. Fielding, J. Gettys,
     J. Mogul, H. Frystyk, T. Berners-Lee. January 1997. (Format:
     TXT=378114 bytes) (Status: PROPOSED STANDARD)

Well, you get the idea.


next up previous contents
Next: 14. Permission and Modification Up: rute Previous: 12. Using Internet Services   Contents