<!doctype linuxdoc system>

<article>

<title>Installing IRC - The Internet Relay Chat Program
<author>SGML version by Christophe Kalt, updated by Piotr Kucharski
<date>$Id: INSTALL.sgml,v 1.87 2010/08/11 17:36:56 bif Exp $
<abstract>
This document describes how to install, and configure IRC 2.11
</abstract>

<sect>Installing IRC.
<sect1>The configure script
<p>
This package uses a GNU configure script for its configuration.
You simply need to untar the distribution and run the
``configure'' script.  This will run configure which will probe
your system for any peculiarities it has and setup the Makefile
and a file of default &num;define's (&dollar;arch/setup.h).
<p>
There are a few options to ``configure'' to help it out, or
change the default behaviour:
<descrip>
<tag/--prefix=DIR/ changes the default directory into which
ircd will install using ``make install''.  This defaults
to /usr/local
<tag/--sbindir=DIR/ changes the default directory where the
system admin executable files will go. It is important to
set this properly. (default is prefix/sbin)
<tag/--sysconfdir=DIR/ changes the default directory where
the irc server configuration files will go. (default is prefix/etc)
<tag/--localstatedir=DIR/ changes the default directory
where the irc server state files will go. (default is prefix/var)
<tag/--with-logdir=DIR/ changes the default directory where the
irc log files will go. (default is localstatedir/log)
<tag/--with-resconf=FILE/ defines the file to be used by ircd to
initialize its resolver.  (default is /etc/resolv.conf)
<tag/--zlib-include=DIR/ specifies in which directory the
include file from the zlib is located.
<tag/--zlib-library=DIR/ specifies in which directory the
zlib library is located.
<tag/--zlib-prefix=DIR/ specifies the prefix for zlib
location.  It overrides the 2 previous options.  (The
include directory is supposed to be in prefix/include, and
the library in prefix/lib).
<tag/--with-zlib/ is the default.  ``configure'' looks on your
system to find the zlib.  If found, ircd will be linked using
it.  This does NOT mean you can use server link compression,
for this you also need to define ZIP_LINKS (see section below).
<tag/--without-zlib/ tells ``configure'' not to look for the zlib.
Defining this will keep you from using server link compression.
<tag/--enable-ip6/ Enable IPv6 support (See notes below)
<tag/--enable-dsm/ Enable Dynamically Shared Modules support for iauth
</descrip>

<sect1>Notes for Cygwin32 users
<p>
The daemon of 2.11 release compiles properly on W32
systems which have the GNU-Win32 environment (<url
url="http://www.cygwin.com/">) setup.  At the
time of the release, tests were made using the version b20.1
of the Cygwin32 library.
<p>
When compiling on such system, you want to make sure that
you have carefully followed the Cygwin32 installation
notes. 
<p>
Also, the IRC server needs a <bf>resolv.conf</bf> file in
order to initialize the resolver.  This file can be anywhere
(see configure options), and is typically in <bf>/etc</bf>
on UNIX systems.

<sect1>Notes concerning IPv6 support
<p>
This version was tested on the following IPv6 systems:
BSD/OS+KAME, Digital Unix, FreeBSD+KAME, Linux, NetBSD+INRIA.
<p>
Because IPv6 numeric addresses contain ``:'' characters,
<bf>the default separator for the server configuration file is
changed to ``%''</bf>. You can adjust it to your needs in config.h file.

<sect>The config.h file
<p>
The second step consists of defining options before the
compilation.  This is done by editing the ``config.h'' file
and changing the various &num;DEFINE's.

<sect1>DEBUGMODE
<p>
<bf>This should only be defined for test purposes, and never
used on a production server.</bf>
<p>
Define DEBUGMODE if you want to see the ircd debugging
information as the daemon is running. Normally this function
will be undefined as ircd produces a considerable amount of
output.  DEBUGMODE must be defined for either of -t or -x
command line options to work.  Defining this induces a large
overhead for the server as it does a large amount of self
diagnostics whilst running.

<sect1>CHROOTDIR
<p>
To use the CHROOTDIR feature, make sure it is &num;define'd
and that the server is being run as root. Better use some
other (external) way of setting up chroot environment for ircd
and run it from there, not requiring to run as root.

<sect1>USERS_RFC1459, USERS_SHOWS_UTMP
<p>Leaving USERS_RFC1459 undefined makes ircd return RPL_LOCALUSERS
and RPL_GLOBALUSERS numerics (part of NAMES). Defining USERS_RFC1459
makes USERS command to behave like it is defined in RFC. If defined,
security conscious server admins may still wish to leave USERS_SHOWS_UTMP
undefined, effectively disabling the USERS command which can be used to 
glean information the same as finger can.

<sect1>ENABLE_SUMMON
<p>ENABLE_SUMMON toggles whether the server will attempt
to summon local users to irc by writing a message similar to
that from talk(1) to a user's tty.

<sect1>DEFAULT_INVISIBLE
<p>
The DEFAULT_INVISIBLE define is used to toggle whether
clients are automatically made invisible when they register.

<sect1>OPER_KILL, OPER_CONNECT, OPER_DIE, OPER_REHASH, OPER_RESTART, OPER_SET...
<p>Any operator priviledge can be precisely applied to a given user using O:line
flags. Some admins may prefer to feel more safe by undefining some of above
thus disabling access to corresponding command at all.

<sect1>ZIP_LINKS, ZIP_LEVEL
<p>
As of the 2.9.3 version of the server, server-server
connections may be compressed using the zlib.  In order to
compile the server with this feature, you MUST have the zlib
package (version 1.0 or higher) already compiled and define
ZIP_LINKS in the config.h file. Compression use for
server-server connections is separately configured in the
ircd.conf file for each server-server link.  ZIP_LEVEL
allows you to control the compression level that will be
used.  Values above 5 will noticeably increase the CPU used
by the server.
<p>
The zlib package may be found at <url
url="http://www.gzip.org/zlib/">. The data format used
by the zlib library is described by RFCs (Request for
Comments) 1950 to 1952 in the files <url
url="ftp://ds.internic.net/rfc/rfc1950.txt"> (zlib format),
rfc1951.txt (deflate format) and rfc1952.txt (gzip
format).

<sect1>SLOW_ACCEPT
<p>
This option is undefined by default, however is needed on some
OSes.  It creates an artificial delay in processing incoming
connections.  On a given port, no more than 1 connection per
2 seconds will be processed.
<p>
As it is undefined, it lets the server process connections as
fast as it can which can cause problems on some OSes (such
as SunOS) and be abused (fast massive join of clonebots..),
for these reasons, if you decide to keep SLOW_ACCEPT undefined
you MUST define CLONE_CHECK.

<sect1>CLONE_CHECK
<p>
This option is defined by default and acts as a wrapper, by
checking incoming connections early before starting ident query.
By default, the server will not accept more than 10 connections from the
same host within 2 seconds.

<sect1>LOG_SERVER_CHANNELS
<p>This option allows you to log to files server channels (like &amp;NOTICES)
chosen via LOG_SCH_* defines. Very handy.

<sect1>Other &num;define's
<p>
The rest of the user changable &num;define's should be
pretty much self explanatory in the config.h file.  It is
*NOT* recommended that any of the file under the line with
"STOP STOP" in it be changed.

<sect>Editing the Makefile, and compiling
<p>
This package now uses GNU autoconf to probe your system and
generate the correct Makefile.  However you may need to read
it to check for values generated by the configure script.
In particular, all the filenames, and path for binaries, log
files, configuration files and so on are defined there.  It
is recommended to make use of the options described in the
``configure script'' section rather than to edit the
generated Makefile.  However, these options do not
provide a total control over these values, in which case you
need to directly edit the Makefile.
<p>
Now to build the package, type ``make all''.  If everything
goes will, you can then install it by typing ``make install''.
<p>
If you have trouble compiling ircd, copy Makefile.in to
Makefile and edit Makefile as appropriate.
<p>
If everything went fine, the default layout of installed files is
as follows (note that existing iauth.conf and ircd.motd will not be
overwritten):
<verb>
PREFIX/sbin/ircd
PREFIX/sbin/iauth
PREFIX/sbin/chkconf
PREFIX/sbin/ircd-mkpasswd
PREFIX/sbin/ircdwatch
PREFIX/man/man8/ircd.8
PREFIX/man/man8/iauth.8
PREFIX/man/man8/ircdwatch.8
PREFIX/man/man5/iauth.conf.5
PREFIX/etc/ircd.m4
PREFIX/etc/ircd.conf.example
PREFIX/etc/iauth.conf.example
PREFIX/etc/iauth.conf
PREFIX/etc/ircd.motd
PREFIX/var/run/
PREFIX/var/log/
</verb>
Files created by ircd package during normal execution would be ircd.pid, ircd.tune,
iauth.pid, ircdwatch.pid in PREFIX/var/run/ and ircd.users, ircd.rejects, ircd.auth,
ircd.opers, ircd.debug, iauth.debug in PREFIX/var/log/.

<sect>The ircd.conf file
<p>
After installing the ircd and irc programs, edit the
ircd.conf file as per the instructions in this section and
install it in the location you specified in the config.h
file.  There is a sample conf file called ircd.conf.example in
the doc/ directory.
<p>
Appendix A (See INSTALL.appendix) describes the differences
between IP addresses and host names.  If you are unfamiliar
with this, you should probably scan through it before
proceeding.
<p>
The ircd.conf file contains various records that specify
configuration options.  The record types are as follows:
<enum>
<item>Machine information   (M)
<item>Administrative info   (A)
<item>Port connections      (P)
<item>Connection Classes    (Y)
<item>Client connections    (I,i)
<item>Operator privileges   (O,o)
<item>Excluded accounts     (K,k)
<item>X Excluded accounts   (X)
<item>Server connections    (C,c,N)
<item>Deny auto-connections (D)
<item>Hub connections       (H)
<item>Leaf connections      (L)
<item>Version limitations   (V)
<item>Excluded machines     (Q)
<item>Service connections   (S)
<item>Bounce server         (B)
</enum>
<p>
Except for types ``M'' and ``A'', you are allowed to have
multiple records of the same type.  In some cases, you can
have concurrent records.  <bf>It is important to note that
the last matching record will be used</bf>.  This is
especially useful when setting up I records (client
connections).

<descrip>
<tag/NEW!!!/ As of the 2.11.0 version of the server, if the 
server has been compiled with #define CONFIG_DIRECTIVE_INCLUDE, you will be
able to use #include directive in ircd.conf to include files without
the need of M4, also recursively.
<verb>#include "filename"</verb>
For the command to be recognized, `#' MUST be first character in the line
and there must be space after "include" word. Quotes around filename are
optional.
If filename does not start with slash, ircd config directory is prepended.
Also note that chkconf will follow such includes.
</descrip>

<sect1>Machine information
<p>
<descrip>
<tag/Introduction/ 
IRC needs to know a few things about your UNIX site, and the
``M'' command specifies this information for IRC.  The fomat
of this command is:
<tag/Format/ 
<verb>M:&lt;Server NAME&gt;:&lt;YOUR Internet IP&num;&gt;:&lt;Geographic Location&gt;:&lt;Port&gt;:&lt;SID&gt;:</verb>
<tag/M/ 
``M'' specifies a Machine description line
<tag/Server NAME/ 
The name of YOUR server adding any Internet DOMAINNAME that
might also be present. If this hostname can be resolved, the
IP&num; found will be used to for outgoing connections.
Otherwise the default interface address of the host is used.
The server name may not be FQDN of another host.  (This
means all outgoing connections will be done from the same
IP&num;, even if your host has several IP&num;).
<tag/YOUR Internet IP&num;/ 
If the machine on which you run the server has several IP
addresses, you can define which IP&num; to use for outgoing
connections.  This overrides overrides the ``Server NAME''.
<p>See Also the ``Port Connections'' and ``Server Connections''
sections.
<tag/Geographic Location/ 
Geographic Location is used to say where your server is, and
gives people in other parts of the world a good idea of
where you are!  If your server is in the USA, it is usually
best to say: &lt;CITY&gt; &lt;STATE&gt;, USA.  Like for
Denver I say: ``Denver Colorado, USA''.  Finnish sites (like
tolsun.oulu.fi generally say something like ``Oulu,
Finland''.
<tag/Port/ 
Defines the port on which your server will listen for UDP
pings from other servers.  This should be the port were
other servers are set to autoconnect.  (Also see the port
field description in connect lines).
<tag/SID/
Defines Server ID, network-wide unique identifier of
your server. It must begin with a digit. This must be set with
cooperation of other servers' admins. On IRCnet you must
consult your coord and/or admins of your peers.
<tag/Example:/ 
M:tolsun.oulu.fi::Oulu, Finland:6667:00PA:
<p>
This line reads: My Host's name is ``tolsun.oulu.fi'', my
site is located in ``Oulu, Finland'' and my SID is ``00PA''.
<p>
M:orion.cair.du.edu::Denver Colorado, USA:6667:00PS:
<p>
This line reads: My Hosts name is ``orion.cair.du.edu'',
my site is located in ``Denver Colorado, USA'' and my SID is ``00PS''.
<tag/Note/ Using ``*'' as &lt;Your Internet IP&gt; allows OS to
choose best outgoing source IP. See also <bf>Server Connections</bf> 
section for configuring source IP of outgoing connections.
</descrip>
<p>

<sect1>Administrative info
<p>
<descrip>
<tag/Introduction/ The ``A'' line is used for administrative
information about a site. The e-mail address of the person
running the server should be included here in case problems
arise.
<tag/Format/<verb>A:&lt;Your Name/Location&gt;:&lt;Your E-Mail Addr&gt;:&lt;other&gt;::&lt;network name&gt;:</verb>
<tag/A/This specifies an Admin record.
<tag/Your Name &amp; Location/ Use this field to say tell
your FULL NAME and where in the world your machine is.  Be
sure to add your City, State/Province and Country.
<tag/Your Electronix Mailing Addr/ Use this field to specify
your Electronic Mailing Address preferably your Internet
Mailing Address.  If you have a UUCP or ARAPnet address -
please add that as well.  Be sure to add any extra DOMAIN
information that is needed, for example ``mail jtrim@orion''
probably won't work as a mail address to me if you happen to
be in Alaska.  But ``mail jtrim@orion.cair.du.edu'' would
work because you know that ``orion'' is part of the DOMAIN
``cair.du.edu''.  So be sure to add your DOMAINNAMES to your
mailing addresses.
<tag/Other/ This is really an OTHER field - you can add what
you want here.
<tag/Network name/ Use this field to announce your network name
in 005 numerics. Use only one word!
<tag/Example/
(the line is just one line in the confuration file, here it
is cut into two lines to make it clearer to read):
<p>
A:Jeff Trim -  Denver Colorado, USA:INET jtrim@orion.cair.du.edu UUCP {hao,isis}!udenva!jtrim:Terve! Heippa!  Have you said hello in Finnish today?;)::IRCnet:
<p>
Would look like this when printed out with the /admin command:
<p>
Jeff Trim -  Denver Colorado, USA
INET jtrim@orion.cair.du.edu   UUCP {hao,isis}!udenva!jtrim
Terve! Hei! Heippa!  Have you said hello in Finnish today? ;)
<p> 
Note that the A record cannot be split across multiple
lines; it will typically be longer than 80 characters and
will therefore wrap around the screen.
</descrip>

<Sect1>Port connections
<p>
<descrip>
<tag/Introduction/ The port line adds flexibility to the
server's ability to accept connections. By use of this line
in the ircd.conf file, it is easy to setup both Unix Domain
ports for the server to accept connections on as well as
extra internet ports.
<tag/Format/<verb>P:&lt;Internet IP&num;&gt;:::&lt;Port&gt;::&lt;Flags&gt;:
P:&lt;Directory&gt;:::&lt;Port&gt;::&lt;Flags&gt;:</verb>
</descrip>
<itemize>
<item>Internet Ports
<descrip>
<tag/Internet IP&num;/ If the host on which the server runs has
several IP addresses, you can define for which IP address
connections will be accepted. If none is defined here, server
will bind to all interfaces (INADDR_ANY).  See also <bf>Machine
configuration</bf> and <bf>Server Connections</bf> sections
to properly configure outgoing connections.
<tag/Port/ The port number field tells the server which port
number it should listen on for incoming connections.
<tag/Example/ P:192.168.1.194:::6664:
<p>
Listens for incoming connections on IP 192.168.1.194, port 6664.
</descrip>
<item> Unix Socket Ports.
<descrip>
<tag/Directory/ The path set in this field should be the
directory name in which to create the unix socket for later
listening to. The server will attempt to create the
directory before creating the unix socket.
<tag/Port/ The port field when used in combination with a
pathname in a P-line is the filename created in the
directory set in the first field.
<tag/Example/ P:/tmp/.ircd:::6667:
<p>
Creates a unix socket in the /tmp/.ircd directory called
``6667''. The unix socket (file) must be a numerical.
</descrip>
</itemize>
<descrip>
<tag/Flags/ Flags changing behaviour of a given P-line. It can be empty
or one of:
<itemize>
<item>D - delayed accept (not active until first netjoin)
<item>S - server-only (user connections are rejected)
</itemize>
Using 'D' flag is a nice way to help network not get invaded after restart. It
does not enable listening socket on a given port before server has a chance to
join a network. Note that you can change state of the listening sockets using
SET CACCEPT oper command. Current state of sockets can be seen with STATS P
(case sensitive).
<tag/Note/ You need at least one P-line or server won't start.
(Unless you run it from inetd.)
</descrip>

<sect1>Connection Classes
<p>
<descrip>
<tag/Introduction/ To enable more efficient use of
MAXIMUM_LINKS, connection classes were implemented.  All
clients belong to a connection class.
<p>Each line for a server should have the same number as the
sixth field.  If it is absent, the server deaults it to 0,
using the defaults from the config.h file.
<p>To define a connection class, you need to include a Y:
line in the ircd.conf file.  This enables you to define the
ping frequency, connection frequency (for servers) and
maximum number of links that class should have.
<p>Currently, the Y: line <bf>MUST</bf> appear in the
ircd.conf file <bf>BEFORE</bf> it is used in any other way.
<tag/Format/<verb>Y:&lt;Class&gt;:&lt;Ping Freq&gt;:&lt;Connect Freq&gt;:&lt;Max Links&gt;:&lt;SendQ&gt;:&lt;Local Limit&gt;:&lt;Global Limit&gt;:&lt;CIDR Limit&gt;</verb>
<tag/Y/ This specifies a Class record.
<tag/Class/ This is the class number which gains the following
attributes and should match that which is on the end of the
C/c/N/I/O/S line.
<tag/Ping Frequency/ This field defines how long the server will let
the connection remain ``silent'' before sending a PING message
to make sure it is still alive.  Unless you are sure of what
you are doing, use the default value which is in your
config.h file.
<tag/Connect Frequency/ By changing this number, you change
how often your server checks to see if it can connect to
this server. If you want to check very occasionally, use a
large value, but if it is an important connection, you might
want a smaller value so that you autoconnect to it as soon as
possible.
<tag/Max Links/ This field defines the maximum number of
links this class will allow from automatic connections (C
lines).  Using /CONNECT overrides this feature.  Also
defines the maximum number of users in this class for all I/O
lines being in that class (or per I/O line, if defined).
<tag/SendQ/ This field defines the ``SendQ'' (data awaiting to be sent
to the client) value for this class. The format is &lt;x&gt;.&lt;y&gt;
<itemize>
<item> x: defines maximum size of sendq, defaults to QUEUELEN if unset.
<item> y: defines maximum size of sendq during burst, defaults to x if unset.
</itemize>
<tag/Local limit/  This field is used to limit the number
of local concurrent connections.  The format is
&lt;x&gt;.&lt;y&gt;
<itemize>
<item> x: defines the maximum number of clients from the
same host (IP) will be allowed.
<item> y: defines the maximum number of clients from the
same user@host (IP) will be allowed.  Read note below.
</itemize>
Any unset value defaults to 1 (one).
<tag/Global limit/  This field has the same use as the
``Local limit'' field.  But, the connection counts are done
for all clients present on the net instead of only counting
local clients.
<tag/CIDR Limit/ This field is used to limit the number of local
host counts within a given IP network. The format is &lt;x&gt/&lt;y&gt;
<itemize>
<item> x: defines the maximum number of clients from the same network
<item> y: defines the length of the network in CIDR format
</itemize>
<tag/Note/ leaving any of the fields (except SendQ and limits) out
means their value is 0 (ZERO)!!  The SendQ field default
value is dynamically determined. Limits default to 1.1 (one connection)
except CIDR limit, which doesn't apply at all if left empty.
<tag/Note/ If you plan to use the local user@host limit,
please read the following very carefully.  The ``user''
value is the ident reply for the connection.  If no reply
was given then it defaults to ``unknown'' and thus the
effective limit will be per host, not per user@host. Also,
some ident servers return encrypted data which changes for
every connection making the limit void. If you think limits
do not work, check ircd logs, the auth reply can be longer
than what ircd shows on-line.
<tag/Note/ Only the local limitation is accurate.
<tag/Note/ If you define a gobal limit, you should also
define a local limit (same or lower) as it won't take more
CPU and will make the global limit more accurate.
<tag/Note/ The local and global limits only affect users (I
lines), not servers nor services.
<tag/Example/ Y:23:120:300:5:800000:0:0: (server class)
<p>
This defines class 23 to allow 5 auto-connections, which are
checked every 300 seconds.  The connection is allowed to
remain silent for 120 seconds before a PING is sent.  NOTE:
fields 3 & 4 are in seconds.  The SendQ is set to 800000
bytes.
<p>
Y:1:60:0:50:20000:2:5: (client class)
<p>
In case of a client class, the fields are interpreted a bit
differently.  This class (number 1) can be used by up to 50
users.  The connections are allowed to remain silent for 60
seconds before a PING is set.  The SendQ is set to 20000
bytes.  A new connection in this class will only be allowed
if there aren't more than 2 other local connections from the
same IP address, or more than 5 other connections on the net
from the same hostname.
<tag/Note/ The default maxlinks behaviour has changed in 2.11.2,
see config.h for details.
<p>
Y:2:60:0:50:20000:2.1:5: (client class)
<p>
In case of a client class, the fields are interpreted a bit
differently.  This class (number 2) can be used by up to 50
users.  The connections are allowed to remain silent for 60
seconds before a PING is set.  The SendQ is set to 20000
bytes.  A new connection in this class will only be allowed
if there aren't more than 2 other local connections from the
same IP address, 1 local connection from the same user
from the same IP address, or more than 5 other connections
on the net from the same hostname.
<p>
Y:2:60:0:50:20000:2.1:5:4/24 (client class)
<p>
Other numbers are exactly the same as previous. Last field
limits connections within the same /24 to 4 hosts. It does not
matter how many different /24 networks are using this Y:line,
each will have separate count.
</descrip>

<sect1>Client connections
<p>
How to let clients connect to your IRCD.
<descrip>
<tag/Introduction/ A client is a program that connects to
the ircd daemon (ircd).  There are clients written in C, GNU
Emacs Lisp and many other languages.  The ``irc'' program is
the C client.  Each person that talks via IRC is running
their own client.
<p>
The ircd.conf files contains entries that specify which
clients are allowed to connect to your irc daemon.
Obviously you want to allow your own machine's clients to
connect.  You may want to allow clients from other sites to
connect.  These remote clients will use your server as a
connection point.  All messages sent by these clients will
pass through your machine.
<tag/Format/
<verb>I:&lt;TARGET Host Addr&gt;:&lt;Password&gt;:&lt;TARGET Hosts NAME&gt;:&lt;Port&gt;:&lt;Class&gt;:&lt;Flags&gt;</verb>
<tag/Note/Lower case ``i'' is equal to an ``R'' flag in plain ``I''.
Lower case ``i'' will be removed in the next version.
<tag/TARGET Host Addr/Specifies the IP address(es) of the
machine(s) that are allowed to connect.  If ``user@''
prefixes the actual IP address the server will require that
the remote username returned by the ident server be the same
as the one given before the ``@''.  Wildcards are permitted
unless using a bitmask (e.g. 1.2.3.0/24). Note that bitmask
are encouraged over wildcards, as they are more accurate.
<p>Empty field is equal to '*' (matches any).
<tag/Password/The password that must be given by the client
to be allowed on the server.
<tag/TARGET Host NAME/Specifies the host name(s) of the
machines allowed to connect to the server.  If ``user@''
prefixes the actual name the server will require that
the remote username returned by the ident server be the same
as the one given before the ``@''.  Wildcards are permitted,
but <bf>please</bf> rather leave this field empty and use bitmask
in <bf>Host Addr</bf> field.
<p>Empty field matches any. ``*'' also matches any, but it requires working DNS for a client.
<p>Using this field to enforce that clients have no Host Name set
is not working (they will rather be denied connection). Use ``N'' <bf>flag</bf>.
<tag/Port/Specifies the port number for which this
configuration line is valid.  An empty field, or ``0''
matches all ports.
<tag/Class/This field should refer to an existing class.
Connections classes are usefull to limit the number of users
allowed on the server.
<tag/Flags/This field contains flags of an I:line; flags are
one character in size, can be combined and their order does not matter.
<itemize>
<item>D - restricted, when client has no reverse DNS
<item>E - client is exempted from K-lines
<item>e - client is exempted from X-lines
<item>F - fall-through to next I-line if password did not match
<item>I - restricted, when client has no ident.
<item>M - disable resolved host name to be shown
<item>N - disable resolved host name to be used
<item>R - restricted
</itemize>
<tag/Note/Restricted I: line means that
clients matching such I line will not be able to use their operator
privileges (no nick/mode change, no kick). Such users will also
have their username prefixed by +, = or - depending on the ident reply.

<tag/Note/The server checks if the client hostname 
matches the <bf>TARGET Host NAME</bf> field.
If a match is found, server checks <bf>TARGET Host Addr</bf> field.
If a match is found, the client is accepted. Clients host is set
either to its hostname (if available) or, using ``N'' or ``M'' flag, to its IP.
<tag/Note/The difference between ``M'' and ``N'' flags is simple: after host
resolving and I:line matching is done, ``M'' keeps hostname and uses it for
matching in beIR modes and printing in logs, while ``N'' discards it completely.
<tag/Examples/
For example, if you were installing IRC on tolsun.oulu.fi
and you wanted to let your own
clients to connect to your server, you would add this entry
to the file:
<p>
I:::tolsun.oulu.fi::1
<p>
If you wanted to let remote clients connect, you could add
the following line:
<p>
I:::*.edu.edu::1
<p>
and allow any clients from machines whose names end in
``.edu.edu'' to connect with no password.
<p>
I:128.214.6.100::nic.funet.fi::1
<p>
Allow clients from a machine with that IP number <bf>and</bf>
that hostname to connect.
<p>
I::secret:*.tut.fi::1
<p>
Allow clients from machines matching ``*.tut.fi'' to connect
with the password ``secret''.
<p>
I:::*::1
<p>
Allow anyone from anywhere to connect to your server.
<p>
I:::*.fi:6667:1
<p>
Allow clients from machines matching ``*.fi'' to connect on
the port 6667.
<p>
I:135.11.35.0/24::*.net::1
<p>
Allows clients from machines which host name matches
``*.net'' <bf>and</bf> which IP address is within block ``135.11.35.0/24'' to
connect to the server.
<p>I:135.11.35.0/24::::1:N
<p>I:135.11.35.0/24::*.net::1
<p>This set of two I:lines 
allows clients from machines which host name matches
``*.net'' <bf>and</bf> which IP address is within block ``135.11.35.0/24'' to
connect to the server.  If the host name does not match
``*.net'' then another I:line is used and because of ``N'' flag,
the IP address is used for these clients, even if the host name is known.
<p>
I:135.11.35.0/24::::1
<p>
Allows clients from machines which IP address is within block
``135.11.35.0/24'' to connect to the server.  If the host name
is known, is it used as address for these clients.
<p><tag/NEW!!!/ As of the 2.11.0 version of the server, I: line flags
are introduced. 
</descrip>

<sect1>Operator priviliges
<p>
How to become the IRC administrator on your site
<descrip>
<tag/Introduction/ To become an IRC Administrator, IRC must
know who is authorized to become an operator and what their
``Nickname'' and ``Password'' is.
<tag/Format/<verb>O:&lt;TARGET Host NAME&gt;:&lt;Password&gt;:&lt;Nickname&gt;:&lt;Port&gt;:&lt;Class&gt;:&lt;Flags&gt;</verb>
<tag/O/ Specifies Operator record. 
<tag/Note/If you use small letter (``o'') in it, it specifies
a local operator. This is deprecated behaviour, use O:line flags.
Operator rights can be specified in config.h and fine-tuned in ircd.conf.
<tag/TARGET Host NAME/ Tells IRC which host you have the
privileges FROM.  This means that you should be logged into
this host when you ask for the priviliges.  If you specify
``tolsun.oulu.fi'' then IRC will expect your CLIENT to be
connected at ``tolsun.oulu.fi'' - when you ask for OPERATOR
privileges from ``tolsun.oulu.fi''.  You cannot be logged in
at any other host and be able to use your OPERATOR
privileges at tolsun, only when you are connected at TOLSUN
will this work - this is a safeguard against unauthorized
sites.
<tag/Password/ If your AUTHORIZATION Password - this is the
password that let's IRC know you are who you say you are!
Never tell anyone your password and always keep the
``ircd.conf'' file protected from all of the other users.
<tag/Nickname/ The Nickname you usually go by - but you can
make this what you want.
<tag/Port/ Unused.
<tag/Class/ The class field should refer to an existing
class (preferably having a lower number than that for the
relevant I-line) and determines the maximum number of
simultaneous uses of the O-line allowable through the
max. links field in the Y-line.
<tag/Flags/This field contains flags of an O:line; flags are
one character in size, can be combined and their order does not matter.
They define privileges of an operator.
<itemize>
<item>L - local operator (disables all remote functions)
<item>P - removes penalty
<item>p - allows flooding
<item>&amp; - allows joining &amp;CLIENTS
<item>A - enables all flags below
<item>C - allows local and remote CONNECT
<item>c - allows local CONNECT
<item>D - allows DIE
<item>d - allows DNS
<item>e - allows SET
<item>h - allows HAZH
<item>K - allows local and remote KILL
<item>k - allows local KILL
<item>l - allows CLOSE
<item>R - allows RESTART
<item>r - allows REHASH
<item>S - allows local and remote SQUIT 
<item>s - allows local SQUIT
<item>T - allows TKLINE
<item>q - allows KLINE
<item>t - enables full TRACE and STATS L
<item>v - allows SIDTRACE
</itemize>
``L'' flag cannot be overridden by other flags.
If &lt;Flags&gt; field is left empty, no privileges will be granted. 
<tag/Example/ O:orion.cair.du.edu:pyunxc:Jeff::1:A
<p>
There is an OPERATOR at ``orion.cair.du.edu'' that can get
Operator priviliges if he specifies a password of ``pyunxc''
and uses a NICKNAME of ``Jeff'' and is granted all possible privileges.
<tag/Note/ Host NAME accepts IP bitmasks.
<tag/Note/ Some privileges may be disabled during compilation time in config.h.
</descrip>

<sect1>Excluded accounts
<p>
Remove an errant user from IRC on your site.
<descrip>
<tag/Introduction/
Obviously it is hoped that you wouldn't have to use this
command.  Unfortunately sometimes a user can become
unmanageable and this is your only recourse - the KILL USER
command.  THIS COMMAND ONLY AFFECTS YOUR SERVER - if this
user can connect to another server somewhere else in the
IRC network then you would have to talk to the administrator
on that site to disable his access from that IRCD server as
well.
<tag/Format/<verb>
K:&lt;Host Name&gt;:&lt;time interval(s)|comment&gt;:&lt;User&gt;:&lt;port&gt;:
k:&lt;Host Name&gt;:&lt;time interval(s)|comment&gt;:&lt;Auth&gt;:&lt;port&gt;:
</verb>
<tag/K/``K'' tells the IRCD that you are making a KILL USER
command entry.
<tag/Host Name/ In this field you specify the Hostname or
the IP address (Single IP, Wildcard notation or bitmask
notation) that the user is connecting from.  If you wanted
to REMOVE connects to IRC from ``orion.cair.du.edu'' then
you would want to enter ``orion.cair.du.edu''.  If you want
to REMOVE ALL HOSTS access you can use ``*'' (Wild Card
notation) and no matter what host the USERNAME (specified in
Field 4) connects from s/he will be denied access.
<p>
If you specify an IP address, IP mask, or an IP bitmask,
it will match clients connecting from the matching
addresses, no matter if they resolve or not.
<p>
You can prefix an IP address, an IP mask, or IP bitmask by
``='' in which case only non resolving matching hosts will
be banned.
<tag/time interval(s)|comment/ Either leave this field empty
or put a comment, then the line active continuously for the
specified user/host machine.  You may also specify intervals
during the line should be active, see examples below.
<tag/User/ The USERNAME of the user you want removed from
IRC.  For example ``root''.
<tag/Auth/ If the user's ident server replies with the OTHER
type (as opposed to the UNIX type), the reply is not used to
set the user's username.  (lowercase) k lines can be used in
these case to reject users based on their ident reply.
<p>
This field will be matched against the ident server reply.
It is important to note that OTHER replies are prefixed with
a ``-'' by the ircd, while UNIX replies are not.
<tag/Port/ The port on which the Kill line will be
effective. 0 means all ports.
<tag/Examples/ K:orion.cair.du.edu::jtrim:0:
<p> 
If user ``jtrim'' connects to IRC from host
``orion.cair.du.edu'' then IMMEDIATELY REMOVE HIM from my
IRCD.
<p>
k:*.stealth.net::-43589:0:
<p>
If a user connects from any host that has the suffix
``stealth.net'' and if that host ident server returns
``-43589'' - then IMMEDIATELY REMOVE THEM from my IRCD.
<p>
K:*.cair.du.edu::root:0:
<p>
If user ``root'' connects to IRC from any host that has the
suffix ``cair.du.edu'' - then IMMEDIATELY REMOVE THEM from
my IRCD.
<p>
K:*::vijay:0:
<p>
This line reads ``I don't care WHAT HOST user ``vijay'' is
on, I will NEVER allow username ``vijay'' to login to my
IRCD.''
<p>
K:*.oulu.fi:0800-1200,1400-1900:*:0:
<p>
This disallows all users from hosts with enddomain
``oulu.fi'' access to your server between 8 and 12am, 2 and
7pm. Users get kicked off if they're already signed on when
the line becomes active (they'll get a warning 5 minutes
before). Note that this requires ircd to be compiled with
proper #define!
<p>
K:192.11.35.0/24::*:0:
<p>
This line disallows all hosts whose IP address is from network
``192.11.35.0/24'' to login to the ircd.
<p>
K:=192.11.35.0/24::*:0:
<p>
This line disallows all hosts whose IP address is from network
``192.11.35.0/24'' and which didn't resolve to login to the
ircd.
</descrip>

<sect1>X Excluded accounts
<p>
Remove an errant user from IRC on your site.
<descrip>
<tag/Introduction/
Obviously it is hoped that you wouldn't have to use this
command.  Unfortunately sometimes a virus can become
difficult to remove by other means and this is your only recourse - 
the XKILL USER
command.  THIS COMMAND ONLY AFFECTS YOUR SERVER - if this
user can connect to another server somewhere else in the
IRC network then you would have to talk to the administrator
on that site to disable his access from that IRCD server as
well.
<tag/Format/<verb>
X:&lt;USER 1st arg&gt;:&lt;USER 2nd arg&gt;:&lt;USER 3rd arg&gt;:&lt;USER 4th arg&gt;:&lt;Nick&gt;:&lt;Target host addr&gt;
</verb>
<tag/X/``X'' tells the IRCD that you are making an XKILL USER
command entry.
<tag/USER n-th arg/ Given field will be matched against corresponding parameter
of client USER command.  If left empty it matches any.  It may contain wildcards.
<tag/Nick/ If left empty it matches any.  It may contain wildcards.
<tag/Target host addr/ Host or IP address or Network in CIDR format. It makes given
X:line apply only to a selected hosts. May contain wildcards. 
If left empty it matches any.
<tag/Examples/ 
<verb>X:guest:::guest:</verb>
If user registers with the following USER command
<verb>USER guest anything anything :guest</verb>
then IMMEDIATELY REMOVE HIM from my IRCD.
<verb>X:abc:::def:woof:</verb>
If user registers with the following NICK and USER commands
<verb>NICK woof
USER abc anything anything :def</verb>
then IMMEDIATELY REMOVE HIM from my IRCD.
<tag/Note/ You need to compile server with #define XLINE to get this
functionality.
</descrip>

<sect1>Server connections
<p>
How to connect to other servers, How other servers can connect to you
<p>
<bf>WARNING:</bf>
The hostnames used as examples are really only examples and
not meant to be used (simply because they don't work) in
real life.
<p> 
Now you must decide WHICH hosts you want to connect to and
WHAT ORDER you want to connect to them in.  For my example
let us assume I am on the machine "rieska.oulu.fi" and I
want to connect to irc daemons on 3 other machines:
<itemize>
<item>``garfield.mit.edu''        - Tertiary Connection
<item>``irc.nada.kth.se''         - Secondary Connection
<item>``nic.funet.fi''            - Primary Connection
</itemize>
<p> 
And I prefer to connect to them in that order, meaning I
first want to try connecting to ``nic.funet.fi'', then to
``irc.nada.kth.edu'', and finally to ``garfield.mit.edu''.
So if ``nic.funet.fi'' is down or unreachable, the program
will try to connect to ``irc.nada.kth.se''. If
irc.nada.kth.se is down it will try to connect to garfield
and so forth.
<p>
PLEASE limit the number of hosts you will attempt to connect
to down to 3. This is because of two main reasons:
<enum>
<item> to save your server from causing extra load and
delays to users
<item> to save internet from extra network traffic (remember
the old rwho program with traffic problems when the number
of machines increased).
</enum>
<p>
<descrip>
<tag/Format/ <verb>C:&lt;TARGET Host Addr&gt;:&lt;Password&gt;:&lt;TARGET Host NAME&gt;:&lt;TARGET PORT&gt;:&lt;Class&gt;:&lt;Source IP&gt;</verb>
<p>
for example:
<p>
C:nic.funet.fi:passwd:nic.funet.fi:6667:1
<p>
          - or -
<p>
C:128.214.6.100:passwd:nic.funet.fi:6667:1
<p>
          - or -
<p>
C:root@nic.funet.fi:passwd:nic.funet.fi:6667:1
<p>
<tag/C/ This field tells the IRC program which option is
being configured. "C" corresponds to a server Connect
option. 
<tag/TARGET Host Addr/ Specifies the host name or IP address
of the machine to connect to.  If ``user@'' prefixes the
actual hostname or IP address the server will require that
the remote username returned by the ident server be the same
as the one given before the ``@''.
<tag/Password/ The password of the other host.  A password
must always be present for the line to be recognized.
<tag/TARGET Host NAME/ This is the name that the TARGET server will
identify itself with when you connect to it.  If you were
connecting to nic.funet.fi you would receive
``nic.funet.fi'' and that is what you should place in this
field.
<tag/TARGET PORT/ The INTERNET Port that you want to connect
to on the TARGET machine. Most of the time this will be set
to ``6667''.  If this field is left blank, then no
connections will be attempted to the TARGET host, and your
host will accept connections FROM the TARGET host instead.
The port field can contain 2 ports, separated by a . In this
case, the first port is used when auto-connecting, the
second port is used for the UDP pings to the targer server.
It can be negative to disable autoconnects, absolute value
will be used to connect when CONNECT command with port ``0'' is used.
<tag/Class/ The class field should refer to an existing
class and determines the maximum number of simultaneous uses
of the C-line allowable through the max. links field in the
Y-line.
<tag/Source IP/ This field specifies source IP to use for connects
to this server.
<tag/Compressed links/ Server connections can be compressed with the zlib library.  To define a compressed connection, you must have compiled the server with ZIP_LINKS defined, and use a _lowercase_ C line.
<tag/NEW!!!/ As of the 2.11.0 version of the server, <bf>Source IP</bf> field
has been added.
</descrip>
<p>
Some examples:
<itemize>
<item>C:nic.funet.fi::nic.funet.fi:6667:1
<p>
This reads: Connect to host ``nic.funet.fi'', with no
password and expect this server to identify itself to you as
``nic.funet.fi''. Your machine will connect to this host to
port 6667.
<item>C:18.72.0.252:Jeff:garfield.mit.edu:6667:1:192.168.0.18
<p>
This reads: Connect to a host at address ``18.72.0.252'',
using a password of ``Jeff''. 
The TARGET server should
identify itself as ``garfield.mit.edu''.  You will connect
to Internet Port 6667 on this host. This connection will use (your)
source IP of ``192.168.0.18''.
<item>C:irc.nada.kth.se::irc.nada.kth.se:1
<p>
This reads: do not attempt to autoconnect to
``irc.nada.kth.se'', but if ``irc.nada.kth.se'' requests a
connection, allow it to connect.
</itemize>
<p>
Now back to our original problem, we wanted OUR server
CONNECT to 3 hosts,  ``nic.funet.fi'', ``irc.nada.kth.se''
and ``garfield.mit.edu'' in that order.  So as we enter
these entries into the file they must be done in
<bf>reverse</bf> order of how we could want to connect to
them.
<p>
Here's how it would look if we connected ``nic.funet.fi'' first:
<p>
C:garfield.mit.edu::garfield.mit.edu:6667:1
C:irc.nada.kth.se::irc.nada.kth.se:6667:1
C:nic.funet.fi::nic.funet.fi:6667:1
<p>
Ircd will attempt to connect to nic.funet.fi first, then to
irc.nada and finally to garfield.
<p>
<bf>Reciprocal entries:</bf>
Each ``C'' entry requires a corresponding ``N'' entry that
specifies connection priviliges to other hosts.  The ``N''
entry contains the password, if any, that you require other
hosts to have before they can connect to you.  These entries
are of the same format as the ``C'' entries.
<p>    
<descrip>
<tag/Format/ The format for the NOCONNECT entry in the ``ircd.conf'' is:
<verb>N:&lt;TARGET Host Addr&gt;:&lt;Password&gt;:&lt;TARGET Host NAME&gt;:&lt;Domain Mask&gt;:&lt;Class&gt;</verb>
<p>
Let us assume that ``garfield.mit.edu'' connects to your
server and you want to place password authorization
authorization on garfield. The ``N'' entry would be:
<p>
N:garfield.mit.edu:golden:garfield.mit.edu::
<p>
This line says: expect a connection from host
``garfield.mit.edu'', and expect a login password of
``golden'', and expect the host to identify itself as
``garfield.mit.edu''.
<p>
N:18.72.0.252::garfield.mit.edu::
<p>
This line says: expect a Connection from host
``18.72.0.252'', and don't expect login password.  The
connecting host should identify itself as
``garfield.mit.edu''. 
<tag/N/ ``N'' corresponds to a server Noconnect option.
<tag/TARGET Host Addr/ Specifies the host name or IP address
of the machine to connect to.  If ``user@'' prefixes the
actual hostname or IP address the server will require that
the remote username returned by the ident server be the same
as the one given before the ``@''.
<tag/Password/ The password of the other host.  A password
must always be present for the line to be recognized. If
CRYPT_LINK_PASSWORD is defined in config.h, this password
must be crypted.
<tag/TARGET Host NAME/ The full hostname of the target
machine. This is the name that the TARGET server will
identify itself with when you connect to it.  If you were
connecting to nic.funet.fi you would receive
``nic.funet.fi'' and that is what you should place in this
field.
<tag/Domain Mask/ Domain masking, see below.
<tag/Class/ The class field should refer to an existing class.
<tag/Wildcards domains/ To reduce the great amount of
servers in IRCnet wildcard DOMAINS were introduced in
2.6. To explain the usage of wildcard domains we take an
example of such:
<p>
*.de  - a domain name matching all machines in Germany.
<p>
Wildcard domains are useful in that ALL SERVERS in Germany
(or any other domain area) can be shown as one to the rest
of the world. Imagine 100 servers in Germany, it would be
incredible waste of network bandwidth to broadcast all of
them to all servers around the world.
<p>
So wildcard domains are a great help, but how to use them ?
<p>
They can be defined in the N-line for a given connection, in
place of ``Domain Mask'' you write a magic number called
wildcard count.
<p>
Wildcard count tells you HOW MANY PARTS of your server's
name should be replaced by a wildcard. For example, your
server's name is ``tolsun.oulu.fi'' and you want to
represent it as ``*.oulu.fi'' to ``nic.funet.fi''. In this
case the wildcard count is 1, because only one word (tolsun)
is replaced by a wildcard.
<p>
If the wildcard count would be 2, then the wildcard domain
would be ``*.fi''. Note that with wildcard name ``*.fi'' you
could NOT connect to ``nic.funet.fi'' because that would
result in a server name <bf>collision</bf> (*.fi matches
nic.funet.fi).
<p>
I advise you to not to use wildcard servers before you know
for sure how they are used, they are mostly beneficial for
backbones of countries and other large areas with common
domain.
</descrip>
<p>

<sect1>Deny auto-connections
<p>
<descrip>
<tag/Introduction/ D lines were implemented to give server
administrators more control on how auto connections are
done.  This will most likely only be useful for big networks
which have complex configurations.
<tag/Format/<verb>D:&lt;Denied Server Mask&gt;:Denied Class:&lt;Server Name&gt;:Server Class:
</verb>
<tag/Denied Server Mask/ This field is matched against all
servers currently present on the network. If it starts with ``!'',
it reverses the meaning of search.
<tag/Denied Class/  If this field contains a class number,
it will match if any server in that class is currently
present on the network.  Note that this can be true for any
server, even the ones not directly connected.
<tag/Server Name/ This field is matched against the server
name that the server wants to auto connect to.
<tag/Server Class/ This field is used to match against the
class to which belong the servers for which an autoconnect
is set.
<tag/Examples/D:*.edu::*.fi::
<p>
Don't auto-connect to any ``*.fi'' server if any server
present on the network matches ``*.edu''.
<p>
D:!*.edu::*.fi::
<p>
Don't auto-connect to any ``*.fi'' server if none of the servers
present on the network matches ``*.edu''.
<p>
D::2:eff.org:3:
<p>
Do not auto-connect to ``eff.org'', or any server in class
``3'' if a server defined to be in class ``2'' is currently
present on the network.
</descrip>

<sect1>Hub connections
<p>
<descrip>
<tag/Introduction/ In direct contrast to L-lines, the server
also implements H-lines to determine which servers may act
as a hub and what they may ``hub for''.  If a server is only
going to supply its own name (ie act as a solitary leaf)
then no H-line is required for, else a H-line must be added.
<tag/Format/<verb>H:&lt;Server Mask&gt;:&lt;SID Mask&gt;:&lt;Server Name&gt;::
</verb>
<tag/Server Mask/ All servers that are allowed via this
H-line must match the mask given in this field.
<tag/SID Mask/ SIDs of all servers that are allowed via this
H-line must match the mask given in this field. Empty field is
equal to '*', that is any SID is allowed to be introduced.
<tag/Server Name/ This field is used to match exactly
against a server name, wildcards being treated as literal
characters.
<tag/Examples/H:*.edu::*.bu.edu::
<p>
Allows a server named ``*.bu.edu'' to introduce only servers
that match the ``*.edu'' name mask, no matter what SID they have.
<p>
H:*:616*:eff.org::
<p>
Allows ``eff.org'' to introduce (and act as a hub for) any
server which SID begins with ``616''.
<tag/Note/ It is possible to have and use multiple H-lines
(or L-lines) for the one server.  eg:
<p>
<verb>H:*.edu:*:*.bu.edu::
H:*.au:*:*.bu.edu::
</verb>
<p>
is allowed as is
<p>
<verb>L:*.edu:*:*.au::
L:*.com:*:*.au::
</verb>
</descrip>

<sect1>Leaf connections
<p>
<descrip>
<tag/Introduction/ To stop servers which should only act as
leaves from hubs becoming hubs accidently, the L line was
introduced so that hubs can be aware of which servers should
and shouldnt be treated as leaves. A leaf server is supposed
to remain a node for the entirity of its life whilst
connected to the IRC server network.  It is quite easy,
however for a leaf server to be incorrectly setup and create
problems by becoming a node of 2 or more servers, ending its
life as a leaf. The L line enables the administrator of an
IRC ``Hub server'' to ``stop'' a server which is meant to
act as a leaf trying to make itself a hub.  If, for example,
the leaf server connects to another server which doesnt have
an L-line for it, the one which does will drop the
connection, once again making the server a leaf.
<tag/Format/<verb>L:&lt;Server Mask&gt;:*:&lt;Server Name&gt;:&lt;Max Depth&gt;:</verb>
<tag/Server Mask/ Mask of which servers the leaf-like
attributes are used on when the server receives SERVER
messages.  The wildcards * and ? may be used within this
field for matching purposes.  If this field is empty, it
acts the same as if it were a single * (ie matches
everything).
<tag/Server Name/ The name of the server connected to you
that for which you want to enforce leaf-like attributes
upon.
<tag/Max Depth/ Maximum depth allowed on that leaf and if
not specified, a value of 1 is assumed.  The depth is
checked each time a SERVER message is received by the
server, the hops to the server being the field checked
against this max depth and if greater, the connection to the
server that made its leaf too deep has its connection
dropped.  For the L-line to come into effect, both fields, 2
and 4, must match up with the new server being introduced
and the server which is responsible for introducing this new
server.
</descrip>

<sect1>Version limitations
<p>
<descrip>
<tag/Introduction/ V-lines are used to restrict server
connecting to you based on their version and on compile time
options.
<tag/Format/<verb>V:&lt;Version Mask&gt;:&lt;Flags&gt;:&lt;Server Mask&gt;::</verb>
<tag/Version Mask/ The matching version number strings will be rejected.
<tag/Flags/ If any flag specified in this field is found in
the peer's flags string, it will be rejected.
<tag/Server Mask/ This field is used to match server names.
The V line will be used for servers matching the mask given
in this field.
<tag/Server Type/ Both the <bf>Version Mask</bf> and the
<bf>Flags</bf> should be prefixed with the server type
identification.  This implementation uses the id
``<bf>IRC</bf>'' (starting with version 2.10).
<tag/Examples/V:IRC/021001*::*::
<p>
Disallows any ``IRC'' server which version is 2.10.1* to connect.
<p>
V:IRC/021001*:IRC/D:*::
<p>
Disallows any ``IRC'' server which version is 2.10.1* or
which has been compiled with DEBUGMODE defined to connect.
<p>
V:*/0209*::::
<p>
Disallows any server using the 2.9 protocol to connect.
<tag/Note/  It is possible to have and use multiple V-lines
for the one server mask.
<p>
V:IRC/021001*::*::
<p>
V:IRC/021002*::*::
<p>
is allowed.
<tag/Protocol Version/ Only the 4 first digit of the
<bf>Version Number</bf> are standard: they define the
protocol version.  The remaining of the string is
implementation dependant; matches on this part should be
used with particular identification.
<tag/Flags/ are not standard.  Therefore, this field
<bf>should always</bf> contain a specific identification.
</descrip>

<sect1>Excluded machines
<p>
Disallowing SERVERS in your irc net.
<descrip>
<tag/Introduction/ In some cases people run into
difficulties in net administration.  For one reason or
another you do not want a certain server to be in your net
(for example because of the security holes it opens for
every server if it's not secured carefully). In that case
you should use Q-lines in your server. When you specify a
server name in Q-line, everytime some server link tries to
introduce you a server (remember, all server names are
broadcast around the net), that name is checked if it
matches the Q-lines in your server. If it matches, then
<bf>your server</bf> disconnects the link. Note that just
placing Q-lines to your server probably results in <bf>your
server</bf> being left alone, unless other servers have
agreed to have the same Q-line in their ircd configuration
files as well.
<tag/Example/Q::of the security holes:foo.bar.baz::
<p>
This command excludes a server named ``foo.bar.baz'', the
reason is given to be security holes (you should give a
reason, it is polite). The first field is unused, so leave
it empty.
</descrip>

<sect1>Service connections
<p>
<descrip>
<tag/Introduction/ The Service is a special kind of IRC
client. It does not have the full abilities of a normal user
but can behave in a more active manner than a normal
client.
<p>
Services are not intended for interactive usage, and are
better suited for automated clients.
<tag/Format/<verb>S:&lt;TARGET Host Mask&gt;:&lt;Password&gt;:&lt;Service Name&gt;:&lt;Service Type&gt;:&lt;Class&gt;</verb>
<tag/TARGET Host Mask/ The host mask should be set to match
the host(s) from which the service will be connecting
from. This may be either an IP&num; or full name (prefered).
<tag/Password/ This is the password which must be passed in
the SERVICE command.
<tag/Service Name/ The name used by the service. Services
don't have nicknames, but a static name defined by the S
line.
<tag/Service Type/ The type of service. It defines the
priviledges given to the service. Be very careful in the
types you allow.  The types can be found in
include/service.h
<tag/Class/ The class field should refer to an existing class.
<tag/Notes/ A service is not a very useful sort of client,
it cannot join channels or issue certain commands although
most are available to it. Services are rejected upon sending
an unknown or unallowed command. Services however, are not
affected by flood control and can be granted special
privileges. It is therefore <bf>wise to oversee the use of
S-lines with much care.</bf>
</descrip>

<sect1>Bounce server
<p>
<descrip>
<tag/Introduction/ This provides you a way to bounce clients
to another server.  This information is provided to clients
which are denied connection, either because their connection
class is full, or the server is full, or they are not
authorized to connect.
<tag/Format/<verb>B:&lt;Class|Host Mask&gt;::&lt;Server Name&gt;:&lt;Port&gt;:</verb>
<tag/B/ This specifies a Bounce record.
<tag/Class|Host Mask/ This field specifies to which client
this configuration line applies to.  It can be either a
connection class number, a host mask to be matched against
the client's hostname, or an IP address/mask/bitmask to be
matched against the client's IP address.
<p>
When the server is completely full, it rejects clients with
the ``All connections in use'' message.  In this case, the
server doesn't process the connections at all, and has no
knowledge of the client's host name, or class number.  For
these cases, this field must be empty.
<tag/Note/ Class number ``-1'' is used for rejecting clients
that use wrong (server-only) port.
<tag/Server Name/ This specifies the IRC server hostname
that the client should use.
<tag/Port/ This specifies the IRC server port that the
client should connect to.
<tag/Example/B:2::irc.stealth.net:6660:
<p>
Rejected clients in class 2 are advised to use
``irc.stealth.net'' on port 6660.
<p>
B:*.fi::irc.funet.fi:6667:
<p>
Finnish client should use irc.funet.fi when they cannot be
taken anymore.
<p>
B:::irc2.stealth.net:6667:
<p>
When the server is completely full, clients should use the
secondary server.

B:-1::our.server.example:6667:

Clients that connected to server-only port should really use port 6667.
</descrip>

<sect>Related resources
<p>
<descrip>
<tag/Mailing list/ A list is dedicated to the people using
ircd. If you have trouble running ircd, or wish to discuss
the future, you can subscribe by sending an email to
<htmlurl url="mailto:majordomo@irc.org"
name="majordomo@irc.org">, with ``<bf>subscribe
ircd-users</bf>'' in the body.
<p>
If you just have a question and don't want to subscribe to
the list, mail to <htmlurl url="mailto:ircd-users@irc.org"
name="ircd-users@irc.org">.  Be sure to indicate which
version you are using.
<tag/Development/ Technical discussions and development are
carried on ircd-dev@irc.org.  People interested in very
early testing, and/or working on the source code are
welcome.  This is done by sending an email to <htmlurl
url="mailto:majordomo@irc.org"
name="majordomo@irc.org">, with ``<bf>subscribe
ircd-dev</bf>'' in the body.
<tag/FAQ/ It can be found on the WWW, at <url
url="http://www.irc.org/tech_docs/ircnet/faq.html">.
<tag/WWW/ Several pages related to the ircd: <url
url="http://www.irc.org/techie.html">.
</descrip>

<sect>Reporting a bug
<p>
If you encounter a bug in the software, here is how and
where to report it.

<sect1>How to report a bug
<p>
To save everyone time, make sure that your e-mail contains
all the information related to your problem.  In particular,
we need to know:
<descrip>
<tag/Package version/
The IRC software version you are using: please include the
output obtained by running ``irc -v'' for the client, and/or
``ircd -v'' for the server.
<p>
Also, let us know if you have applied any patch to the
package or if it is the vanilla version.
<tag/OS/
Please, indicate which OS version you are running.
<tag/Configuration/
If it is related to a configuration problem with the server,
include the relevant parts of the configuration file.
<tag/Backtrace/
If the bug results in a crash, please include the
backtrace.  (This can be done, for example, by running
``gdb'' on the core file, and typing ``where'').
<tag/Fix/
If you have a fix, don't forget to include it.
</descrip>

<sect1>Where to send a bug report
<p>
Reports should be sent to <htmlurl url="mailto:ircd-bugs@irc.org"
name="ircd-bugs@irc.org">.  Your report will be reviewed
and forwarded to the appropriate mailing list.

</article>
