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  Linux ISP Hookup HOWTO
  Egil Kvaleberg, [e-mail]
  v1.0, 9 March 1996

  This document describes how to use Linux to connect to an Internet
  Service Provider via a dial-up modem connection.  As well as the basic
  dial-up procedure and IP establishment, email and news handling is
  covered.

  1.  Introduction

  This description has been made to answer a few questions about how
  dial-up ISP (Internet Service Provider) subscribers may configure and
  use Linux.

  To ease the burden for those who will connect their Linux based
  machines to an ISP for the first time, an attempt has been made to
  cover most issues encountered.  This quite unavoidably will create a
  certain degree of overlap with other Linux Howto-documents and LDP
  books.  Reference should be made to these documents to provide better
  understanding and detail.

  Much of the existing documentation is targeted towards users with a
  certain degree of experience, and first time users will often have
  trouble sorting out the relevant information.

  To simplify, the examples given will assume the following:

  ╖  User name: dirk

  ╖  Password: PrettySecret

  ╖  Internet service provider: acme.com

  ╖  Email server: mail.acme.com

  ╖  News server: news.acme.com

  ╖  Name server: 193.212.1.0

  ╖  Phone number: 12345678

  Our "dirk" will be calling his machine "roderick".

  All references in the table above should naturally be replaced by
  whatever is valid for the ISP one is using.  Often, just a minimum of
  changes will otherwise be required for users with different ISPs.  I
  would like to be informed about what problems you encounter on this
  account.

  1.1.  New versions of this document

  New versions of this document will be periodically posted to
  comp.os.linux.answers. They will also be added to the various
  anonymous FTP sites who archive such information, including:

  ftp://sunsite.unc.edu/pub/Linux/docs/HOWTO

  In addition, you should generally be able to find this document on the
  Linux WorldWideWeb home page at

  http://sunsite.unc.edu/mdw/linux.html

  Finally, the very latest version of this document should also be
  available in various formats from:

  ftp://ftp.sn.no/user/egilk/ISP-HOWTO.txt

  ftp://ftp.sn.no/user/egilk/ISP-HOWTO.ps.gz

  ftp://ftp.sn.no/user/egilk/ISP-HOWTO.tar.gz

  http://www.sn.no/~egilk/ISP-HOWTO.html

  1.2.  Feedback

  All comments, error reports, additional information and criticism of
  all sorts should be directed to:

  [e-mail]

  http://www.sn.no/~egilk/

  1.3.  Disclaimer

  No liability for the contents of this documents can be accepted.  Use
  the concepts, examples and other content at your own risk.
  Additionally, this is an early version, with many possibilities for
  inaccuracies and errors.

  One of many possible setups will be described. In the Linux world,
  there is usually a number of ways in which to accomplish things.
  Paragraphs containing hints to alternatives are marked by ALT. Please
  also note that FTP-references often will change slightly as new
  versions of programs arrive.

  As far as I know, only programs that under certain terms may be used
  or evaluated for personal purposes will be described. Most of the
  programs will be available complete with source under GNU-like terms.

  1.4.  Copyright information

  This document is copyrighted (c)1996 Egil Kvaleberg and distributed
  under the following terms:

  ╖  Linux HOWTO documents may be reproduced and distributed in whole or
     in part, in any medium physical or electronic, as long as this
     copyright notice is retained on all copies. Commercial
     redistribution is allowed and encouraged; however, the author would
     like to be notified of any such distributions.

  ╖  All translations, derivative works, or aggregate works
     incorporating any Linux HOWTO documents must be covered under this
     copyright notice.  That is, you may not produce a derivative work
     from a HOWTO and impose additional restrictions on its
     distribution. Exceptions to these rules may be granted under
     certain conditions; please contact the Linux HOWTO coordinator at
     the address given below.

  ╖  If you have questions, please contact Greg Hankins, the Linux HOWTO
     coordinator, at [e-mail] via email.  Finger for phone
     number and snail mail address.

  2.  How do I connect to the rest of the world?

  It will be assumed that we have installed the essential networking
  software modules (e.g. essential parts of the Slackware N-series), and
  that you have set up which serial port that is to be used for the
  /dev/modem.

  The default configuration will usually only allow direct access to
  "/dev/modem" as user "root".

  To connect to ISP shell accounts directly, and to experiment with
  connection sequences, you may use the "minicom" program. It is pretty
  straight forward to use.

  2.1.  The basic configuration

  Configuration of the machine for use on the net should be done as user
  "root".  Before proceeding any further, ensure that the file
  "/etc/hosts.deny" contains the following line:

       ALL: ALL

  You would normally want to allow yourself, so add the following line
  to "/etc/hosts.allow":

       ALL: 127.0.0.1

  For the following, note that it is meant for those connected via PPP
  and with a dynamic IP address. If you have the benefit of a fixed con¡
  nection, there will be some differences.

  It is nice to have a name connected to the machine, a name that the
  dynamic IP user really can select as he or she pleases.  Put the name
  in "/etc/HOSTNAME":

       roderick

  The next step is to set up the name server in "/etc/resolv.conf":

       search acme.com
       nameserver 193.212.1.0

  The name server must be specified by a numeric IP address, and will be
  different from ISP to ISP.  If required, you can have up to three dif¡
  ferent servers.  They will be requested in the sequence in which they
  are listed.  A "search" statement has been added to allow abbreviation
  of names like "news.acme.com" to "news".

  A certain minimum of configuration will also be required in
  "/etc/hosts".  Most users will be able to manage with:

       127.0.0.1 localhost
       0.0.0.0   roderick

  Those with a fixed IP-address will obviously replace 0.0.0.0 with
  this.

  Likewise, a minimum "/etc/networks" is:

       loopback  127.0.0.0
       localnet  0.0.0.0

  The username and password at the ISP must be specified in
  "/etc/ppp/pap-secrets"

       dirk * PrettySecret

  For those ISPs using CHAP instead of PAP, the filename is
  "/etc/ppp/chap-secrets".

  Finally, the nitty gritty regarding the connection procedure itself
  must be specified before PPP can be initiated. This is done in
  "/etc/ppp/chatscript":

       TIMEOUT 5
       \Z'\h'(u;\w'x'-\w'┤'/2)'┤'OK ATDT12345678
       ABORT 'NO CARRIER'
       ABORT BUSY
       ABORT 'NO DIALTONE'
       ABORT WAITING
       TIMEOUT 45
       CONNECT ""
       TIMEOUT 5
       "name:" ppp

  Details here may have to be tuned somewhat.  The phone number in the
  third line must of course be set as required.  Some users may need to
  replace the "ATZ" modem initialization string with something more tai¡
  lored for the modem being used.  The last line specifies that one is
  expecting the prompt "name:", and that the response should be "ppp"
  when it arrives. Other systems may have other login procedures.

  To actually initiate a call, the PPP-protocol may be initiated by
  issuing the following command:

  exec pppd connect \
       'chat -v -f /etc/ppp/chatscript' \
        -detach crtscts modem defaultroute \
        user dirk \
        /dev/modem 38400

  We should now be on-air, and stay up until the program is killed by
  typing a Ctrl-C.  Any messages concerning the connection will be
  appended to the system logs. To read them, try:

       trail /var/adm/messages

  As long as PPP is up, you will have direct access to the Internet, and
  may use programs like ftp, ncftp, rlogin, telnet, finger etc.  All
  these programs should be part of the network package.

  Further information concerning PPP is also available from:

  /usr/lib/ppp/README.linux

  /usr/lib/ppp/README.linux-chat

  Finally, an additional word about safety.  The file "/etc/inetd.conf"
  lists all services that your machine will offer externally.  With the
  "/etc/hosts.deny" file we have made, no external access will be
  allowed.  For those who need it, access must be allowed explicitly in
  "/etc/hosts.allow". Local traffic may be allowed by:

       ALL: LOCAL

  See also "man 5 hosts_access".

  A final little thing.  A certain confusion exists regarding the names
  of the POP-protocols.  A definition in "/etc/services" compatible with
  just about everything is:

       pop2      109/tcp   pop-2          # PostOffice V.2
       pop3      110/tcp   pop-3 pop # PostOffice V.3

  ALT Instead of "chatscript", one might use the much more flexible
  "dip". But not in connection with "diald".

  ALT Those lucky enough to have a permanent TCP/IP connection via e.g.
  an Ethernet may safely ignore anything about PPP, and rather start
  concentrating about setting up their network card.

  ALT Others may not have the possibility of using PPP, but may be able
  to use SLIP instead, for which there is support in much the same
  manner as for PPP. Another possibility is UUCP.  Others again may have
  to rely on exchange of news and email be means of SOUP.  A description
  for the latter case may be found in:
  ftp://ftp.sn.no/user/bjorn/Linux-offline.tgz

  The TERM program is also an option. Refer to the "Term-HOWTO".

  3.  How do I "surf"?

  If you think that text is the most important, you might want to use
  the Lynx Web-browser. It is available from:

  ftp://sunsite.unc.edu/pub/Linux/system/Network/info-
  systems/lynx-2.3.bin2.tar.gz

  If you have installed X-windows, you can also use one of the many
  graphical browsers. Chimera may be found at:

  ftp://sunsite.unc.edu/pub/Linux/system/Network/info-
  systems/chimera-1.65.bin.ELF.tar.gz

  http://www.unlv.edu/chimera/

  Mosaic:

  ftp://sunsite.unc.edu/pub/Linux/system/Network/info-
  systems/Mosaic-2.7b1-aout.tgz

  ftp://ftp.NCSA.uiuc.edu/Web/Mosaic/Unix/binaries/2.6

  Mozilla (Netscape):

  ftp://sunsite.unc.edu/pub/Linux/system/Network/info-systems/netscape-
  v11b3.tar.gz

  ftp://ftp.cs.uit.no/pub/www/netscape

  These browsers are constantly available in new and in various ways
  exciting versions.

  Use and evaluation of these programs is subject to certain terms.
  Please observe them.

  4.  How do I send and receive email?

  First of all, ensure that "sendmail" is installed.  Sendmail sorts
  internal and out-bound mail, and will buffer out-bound mail until such
  time it is possible to forward it.

  Sendmail is based on a configuration found in "/etc/sendmail.cf".  An
  example suitable for ISP users can be found in:

  ftp://ftp.sn.no/user/egilk/sendmail.cf

  It is if course required to have an official domain address for out-
  bound mail, something which is specified in "/etc/sendmail.cf":

       # who I masquerade as (null for no masquerading)
       DMacme.com

  Sendmail is now configured for sending directly to the recipient.  To
  avoid long and repeated connections in those cases where the connec¡
  tion to the receiving end is slow and irregular, is is usually nice to
  use ones ISP as a buffer store.  This can be specified by the DS spec¡
  ification:

       # "Smart" relay host (may be null)
       DSmail.acme.com

  Beware that sendmail is somewhat sensitive to handling of tab stop
  characters in "sendmail.cf". You might want to use the "vi" editor to
  ensure that these tab characters are retained unchanged.

  Email reception can often be performed via the POP3 protocol, which
  can be initiated every time the connection is brought up.  A script
  for testing this is:

       sendmail -q
       popclient -3 -v mail.acme.com -u dirk -p "PrettySecret" \
              -k -o /usr/spool/mail/dirk 2> $HOME/pop.log

  This script may be started after PPP connection has been established.
  Beware that this script is just for testing, so ensure that the local
  mailbox is left untouched while it runs.  The "-k" option means that
  the mail is kept in the ISP mailbox, and you are simply given a copy
  of the mail.  You would of course want to remove this option once you
  are confident that your setup is working.

  Beware that the password will show on the command line. This really
  should be fixed ASAP.

  A safe and better version of this script may be found at:

  ftp://ftp.sn.no/user/egilk/pop-script.tar.gz

  This version of the script requires that "procmail" is installed, but
  that is something you'll never regret anyway:

  ftp://sunsite.unc.edu/pub/Linux/system/Mail/mailhandlers/procmail-3.10-2.tar.gz

  Procmail is a simple and flexible tool that can sort incoming email
  based on a large range of criteria. In addition to being able to
  handle automated tasks like vacation messages and such.

  The user interface for reading and sending of email can be found in
  programs like Pine or Elm.

  ALT For an ordinary dial-up ISP user it is not really necessary to
  have the sendmail daemon active. To reduce the resource usage, one may
  thus comment out any startup of sendmail, as is usually found in
  "/etc/rc.d/rc.M".

  ALT In place of sendmail one might use the simpler "smail". You'll
  find a good description of it (as well as most other things mentioned
  here) in the "Linux Network Administrator's Guide".

  ALT There is also an m4 macro package for making a fresh
  "sendmail.cf".  For a simple installation it might be just as well to
  modify an existing configuration.

  ALT There are also simpler although less flexible alternatives. Pine
  may run stand-alone as long as it is configured properly, for
  instance. It might even be possible to use newer versions of some web-
  browsers.

  ALT Many are very enthusiastic regarding the Emacs companion Gnus as
  an email and news handler. Further information can be found at:

  http://www.ifi.uio.no/~larsi/

  ALT An alternative to popclient is "pop-perl5". It is available from:

  ftp://sunsite.unc.edu/pub/Linux/System/Mail/pop-perl5-1.1.tar.gz

  5.  News

  5.1.  How do I set up an online news-reader?

  As long as PPP is active, it will be possible to read news online.
  There are several available programs. One can use the "rtin" or "trn",
  one can configure "pine", or even use a WWW-browser.

  The only thing required in terms of configuration in most cases is to
  do (usually once and for all in the file ".profile"):

       export NNTPSERVER=news.acme.com

  5.2.  How do I set up an offline news-reader?

  To be able to read news while offline, and thus reduce phone bills and
  give greater flexibility, one must set up a local news-spool of one
  sort or the other.  This requires some configuration, and there will
  also be a certain amount of disk space involved.  After initial setup,
  things should run more or less by themselves, with only some attention
  needed from time to time.

  The solution described here is based on the news-server Cnews and the
  NNTP protocol.  Cnews was originally targeted towards another sort of
  configuration, but is flexible enough to handle our situation too.
  One might also use the new and popular Inn news server, but it might
  require a bit more in terms of resources.  Any way, be careful not to
  install both; they don't live together easily.

  It is crucial that all maintenance of news is done while logged in as
  user "news", and that all configuration files is placed in
  "/usr/lib/news". One way of handling this is, while logged in as
  "root" to write "su news; cd".

  The most important files in the configuration are:

  ╖  "active" is an overview over active newsgroups. It is updated as
     required by the command addgroup, e.g. "addgroup
     comp.os.linux.networking y".

  ╖  "organization" should simply contain whatever you want in the
     "Organization:" header field, in our case:

  Dirk Gently's Holistic Detective Agency

  ╖  "mailname" should in our case be set to "acme.com".

  ╖  "whoami" is set to the name of your "site" in the "Path:" thread.
     In a setup as described here, using "postit", this name will never
     leave the machine, so you can set this to whatever you like as long
     as you are pretty sure it is unique. In this case "roderick".

  ╖  "sys" controls fetching and further distribution of news.  We will
     assume the ISP in our case adds "acme.com" to the Path, and that
     this is the only news source we have.  The example given really
     tells that we will accept everything that arrives, and that we will
     only post news to "acme.com" that it hasn't seen before, and is
     originally posted at our own site.  In this simplified setup we
     assume that the decision about which newsgroups to really fetch is
     done by "slurp" (see below).  "/all" specifies the distribution,
     and must be included.  The letter "F" says that (pointers to)
     outgoing news articles will be collected in a file.

       ME:all/all::
       sn/acme.com:all,!junk/all:FL:

  ╖  A subdirectory for the outgoing news must be created, in our case:

       mkdir /var/spool/news/out.going/acme

  ╖  "mailpaths" controls posting in moderated groups, although this
     task may usually be left to the ISP.

  Cnews needs a certain degree of daily maintenance, but this can be
  specified once and for all via the command "crontab -e" issued as user
  "news". A suggested setup follows; it can be tuned as required:

       # maintain incoming and outgoing batches
       10,40 *  * * * /usr/lib/newsbin/input/newsrun

       # expire C-news, once a day
       30 0  * * * /usr/lib/newsbin/expire/doexpire

       # monitor and report if needed
       00 2  * * sat /usr/lib/newsbin/maint/addmissing
       40 3  * * * /usr/lib/newsbin/maint/newswatch
       50 3  * * * /usr/lib/newsbin/maint/newsdaily

  Newsrun moves articles in and out (twice every hour), doexpire will
  delete articles as they get old (every night at 00:30), and the three
  last commands does various supervisory and error correcting tasks.

  One should also ensure that things are cleaned up when starting the
  machine. As user root, add the following line to "/etc/rc.d/rc.local":

       su news -c /usr/lib/newsbin/maint/newsboot

  News may be collected via the program "slurp", picking news from an
  NNTP-server. The program can for instance be found at:

  ftp://sunsite.unc.edu/pub/Linux/apps/comm/slurp-1.10.tar.Z

  Setting up "slurp" is quite simple. The program itself may be copied
  to til /usr/lib/news.  You should also create a
  /usr/lib/news/slurp.sys that describes which newsgroups that you want
  to read. A simple example, collecting all linux groups in addition to
  rec.humor.funny:

       news.acme.com:comp.os.linux.*,rec.humor.funny

  Note that Slurp uses "*" instead of "all".

  Additionally, a file must be created for each news-server, in our case
  "slurp.news.acme.com". The contents of this file reflects the latest
  date/time that news have been collected, and will be updated for every
  news batch.  The file must be initialized (initial date may be set as
  desired):

       960101 000000

  To fetch articles, user "news" issues the following command (assuming
  communication via PPP or similar is up):

       slurp news.acme.com

  The option "-d" gives continuous printout to the screen.

  Most ISPs will not allow posting of news by the NNTP IHAVE-procedure,
  only POST. This requires special handling of news posting. A suitable
  tool can be collected from:

  ftp://ftp.sn.no/user/egilk/postit.tar.gz

  Article transfer may then be performed by:

       postit news.acme.com acme

  To control disposal of articles as they get old, a file "explist" is
  required.  The comments in this example should explain what we want to
  do:

       # hold onto history lines 14 days, nobody gets >120 days
       /expired/           x    14   -
       /bounds/            x    0-1-120 -

       # retain these for 2 months
       comp.sources,comp.os.linux.all     x    60   -

       # noise gets thrown away fast
       junk,control             x    2    -

       # default:  14 days, no archive
       all                 x    14   -

  ALT In a small news-spool, one will often not need the newsgroup
  "control". The traffic is huge compared to the usefulness. The main
  point is that articles will be canceled, and that groups may be
  created automatically.  To ensure that control messages containing
  "newgroup" not shall mess up things for us, a file called
  "newgroupperm" specifies what we will allow:

       comp.os.linux  [e-mail] yv
       all       any       nq

  In this example, all proper groups under comp.os.linux will be created
  (y), and the user "news" will be notified (v).  Everything else will
  be silently (q) ignored (n). The last line is sufficient if you want
  to create all groups manually.

  ALT An alternative to slurp/postit is "suck", that is not using the
  NNTP NEWNEWS command. This program is simple, although quite improved
  compared to the earliest versions.  Version 2.51 will be replaced by
  2.6:

  ftp://sunsite.unc.edu/pub/Linux/system/News/suck-2.5.1.tar.gz

  ALT A different solution altogether is to install the integrated
  package "leafnode". This will handle all tasks required for a personal
  news spool, and is easy to configure.  It is available from:

  http://www.troll.no/freebies/leafnode.html

  6.  How do I automate the connection procedure?

  Automated handling of news and email is quite easy to implement in
  Linux.

  First and foremost one should make a "/usr/lib/ppp/ppp-on" that
  initiates the ISP connection.  Often, this file will simply contain
  the following:

       /usr/sbin/pppd

  Further specification will be performed in "/etc/ppp/options":

       connect "/usr/lib/ppp/chat -v -f /etc/ppp/chatscript"
       crtscts
       modem
       defaultroute
       asyncmap 00000000
       user dirk
       /dev/modem 38400

  To end a connection, use the supplied version of "/usr/lib/ppp/ppp-
  off".

  Having tested the functionality of these two scripts, one must then
  write scripts that perform the various tasks. The script to collect
  email has been described before, and we will here assume it is located
  at "/home/dirk/pop".

  A script for exchange of email can then be produced in "/root/mail":

       #! /bin/sh
       #
       # exchange mail
       # 10 minutes timeout:
       TIMEOUT=600
       DT=10

       # kick sendmail:
       sendmail -q &

       # retrieve mail:
       su dirk -c /home/dirk/pop

       # wait for sendmail to terminate:
       t=0
       while ! mailq | grep -q "Mail queue is empty"; do
           t=$[$t+$DT]
           if [ $t -gt $TIMEOUT ] ; then
            echo "sendmail -q timeout ($TIMEOUT).."
            exit 1
           fi
           sleep $DT
       done

       exit 0

  The script to exchange news may be placed in "/usr/lib/news/news":

  #!/bin/sh
  #
  # exchange news
  # must be run as news:
  cd /usr/lib/news

  #update the outgoing batch (Cnews):
  /usr/lib/newsbin/input/newsrun <lt; /dev/null

  #send batched news:
  /usr/lib/newsbin/postit news.acme.com acme

  #and get the new one:
  slurp news.acme.com

  A script to connect the various bits and pieces remains, and can be
  placed in "/root/news+mail":

       #!/bin/sh
       #
       # exchange news and email
       # must be run as root
       #
       if ! /usr/lib/ppp/ppp-on; then
           exit 1
       fi
       trap "/usr/lib/ppp/ppp-off" 1 2 3 15

       #exchange news+mail:
       /root/mail &
       su news -c ~news/news
       wait

       #disconnect..
       /usr/lib/ppp/ppp-off

       #update the incoming batch (Cnews):
       su news -c /usr/lib/newsbin/input/newsrun <lt; /dev/null &

       exit 0

  It is quite easy to make an extension to the above that only will
  establish a connection if outgoing email and news is present.  Lets
  call it "/root/news+mail.cond", and keep in mind that the name of the
  outgoing news-spool must be updated to suit:

       #!/bin/sh
       #
       # exchange news and email, only if outgoing news or mail
       # (Cnews spool)
       if [ -s /var/spool/news/out.going/acme/togo ] ||
           ! ( mailq | grep -q "Mail queue is empty"); then
            /root/news+mail
       fi

  The only thing remaining is to specify when all this is going to
  happen.  This is done using the command "crontab -e" as root. Let us
  assume that we always want to exchange news and mail at 07:00 in the
  morning, and after that every 4th hour assuming there are outgoing
  email and news:

       00 7      * * *     /root/news+mail
       00 11,15,19,23 * * *     /root/news+mail.cond

  Ensure that every component is tested well before you connect them
  together. One may later add several other tasks, such as adjustment of
  the time of day (using ntpdate), and automatic update (mirroring) of
  locally maintained WWW and FTP files up to the ISP (using make and
  ftp).

  ALT Depending on ones preferences, it is also possible to turn the
  process upside down. Every time a PPP link is initiated, the script
  "/etc/ppp/ip-up" will be started. One may here add whatever magic is
  required to start exchange of email and news. See "man pppd" for
  further detail.

  ALT It is also possible to automatically connect PPP whenever network
  traffic is detected.  This is in many ways the more elegant solution,
  but it is quite dependent on a good configuration to avoid frequent
  (and costly) connections being made.  More information can be found
  at:

  http://www.cs.toronto.edu/~schenk/diald.html

  The "diald" utility is available from:

  ftp://sunsite.unc.edu/pub/Linux/system/Network/serial/diald-0.13.tar.gz

  At the same location one will also find other variations on PPP
  connections.

  7.  Final words

  7.1.  Other things I should know about?

  ╖  Various error messages in the system will normally be issued as
     internal email. To ensure that these will actually be read, one
     should create an "/etc/aliases". Remember the command "newaliases"
     every time you change this. An example that should cover most
     eventualities is:

       PostMaster: root
       ftp: root
       news: root
       usenet: root
       FaxMaster: root
       fax: root
       WebMaster: root
       MAILER.DAEMON: root

  ╖  Many programs for Linux may be found at "Sunsite", which is usually
     quite busy. But there are many mirrors, and every time there is a
     reference to "ftp://sunsite.unc.edu/pub/Linux/.."  one should try
     to use a mirror close to home, e.g.
     "ftp://ftp.nvg.unit.no/pub/linux/sunsite/.."

  ╖  If you happen to be migrating from Yarn, it should be possible to
     convert these to standard folders using the "yarn2mf" available at:

  ftp://ftp.sn.no/user/egilk/yarn2mf.zip

  7.2.  How do I learn more?

  The Linux Documentation Project book called Linux Network
  Administrator's Guide by Olaf Kirch is pretty mandatory for anyone
  that will set up and maintain anything involving TCP/IP and Internet:

  ftp://sunsite.unc.edu/pub/Linux/docs/linux-doc-project/network-
  guide/nag-1.0.ascii.tar.gz

  The documentation that follows each software package will normally
  give you all the detailed information you need, if not always the
  overview. The man-pages will be the first place to look. Try for
  instance:

       man pppd

  You will also find some documentation about certain programs in the
  "/usr/doc" tree, although this is not always well structured.

  The following HOWTOs will be highly relevant:

  ╖  Installation-HOWTO will get the basics sorted.

  ╖  NET-2-HOWTO is a very thorough description of installation and
     setup of the NET code. Much of this should already have been done
     if you use a standard Linux distribution (e.g. Slackware, RedHat,
     Debian). But many sections on setup and troubleshooting will be
     very worthwhile.

  ╖  Mail-HOWTO explains how to configure various tools. Again, much of
     this will already have been done for you when you install a
     standard Linux distribution.

  ╖  News-HOWTO is for setting up a (conventional) news spool.

  ╖  Tiny-News covers yet an alternative to "slurp" of picking up news.

  ╖  PPP-HOWTO is a good description of problems you may encounter when
     setting up a PPP connection.

  ╖  Serial-HOWTO contains everything you need to know about setting up
     serial ports.

  7.3.  Thanks to

  Information here is collected from many sources. Thanks to the
  following that either indirectly or directly have contributed:
       Arne Coucheron      [e-mail]
       Arne Riiber         [e-mail]
       Arnt Gulbrandsen    [e-mail]
       Bjorn Steensrud     [e-mail]
       Gisle Hannemyr      [e-mail]
       Hans Amund Rosbach  [e-mail]
       Hans Peter Verne    [e-mail]
       Harald T Alvestrand [e-mail]
       Haavard Engum       [e-mail]
       Jorn Lokoy          [e-mail]
       Kenneth Tjostheim   [e-mail]
       Kjell M. Myksvoll   [e-mail]
       Kjetil T. Homme     [e-mail]
       Nicolai Langfeldt   [e-mail]
       Ove Ruben R Olsen   [e-mail]
       Steinar Fremme      [e-mail]
       Sverre H. Huseby    [e-mail]
       Trond Eivind Glomsrod    [e-mail]
       Tommy Larsen        [e-mail]