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#!perl -w
# To check its syntax, run this document through perl.
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#	perldoc -tF docs/INSTALL.pod > INSTALL
use Pod::Checker;
podchecker(\*DATA);
__END__

=head1 NAME

INSTALL - Slash Installation

=head1 SYNOPSIS

This document describes how to install Slash, versions 2.2 and
pre-releases of 2.3 and 2.5.  For instructions on installation or upgrade
of previous versions of Slash, see the INSTALL document included with
those distributions.

These instructions have only been tested on Linux.  Installation under
BSD and other Unix OSes is doable, with minor glitches (see L<"BSD
Systems"> below).  Windows is not supported.

Slash can always be downloaded from SourceForge.net, from the FTP site,
and via CVS.

	http://sf.net/projects/slashcode/
	ftp://ftp.slashcode.com//pub/slashcode/
	http://cvs.slashcode.com/

See the SourceForge.net page for patches and bug reports.

=head2 Which version should I use?

First of all: if you are using Slash 2.2.5 or before, including all 2.1.x,
2.0.x, and 1.x versions, you should upgrade to the latest version in
the 2.2 tree, 2.2.6, as soon as possible.  There are security issues
with previous versions.  You should not install previous versions.

As of this writing (August 2006), our last official release (2.2.6) was
long ago, and many features have been added since.  All development has
been in CVS.  If you are installing a new Slash site, you don't want to
use 2.2.6.  And while you probably don't want to use the very latest
CVS, you almost certainly do want to use the latest "R_" tag available
in CVS.  See L<"VERSIONS">, "CVS tags", below, for advice on choosing
and maintaining a CVS installation.

=head2 Read, then install

We know you want to get right into the installation, but you must first
read, carefully, these sections of this INSTALL file:

=over 4

=item *

REQUIREMENTS, to make sure you have the right hardware and software

=item *

"CVS tags," in VERSIONS, to make sure you have the right version
of this code

=item *

SECURITY NOTES, to keep your system safe

=item *

INSTALLATION (the longest section), to make sure you will be able to
finish what you start

=back

And it's a good idea to at least skim:

=over 4

=item *

INSTALLATION OPTIONS

=item *

TROUBLESHOOTING

=back

Read those sections before you begin actually performing the steps in
L<"INSTALLATION">.

This document also contains information on upgrading a Slash site
(which can be tricky), and uninstalling (which is easy).

=head2 Updates to this file

This INSTALL file you are currently reading may not be the latest.
Again, you probably don't want to upgrade your whole Slash checkout to
the very latest CVS.  But if you encounter problems, it might not be
a bad idea to look over the very latest version of this INSTALL file,
which you can find at:

L<http:E<sol>E<sol>slashcode.cvs.sourceforge.netE<sol>*checkout*E<sol>slashcodeE<sol>slashE<sol>INSTALL>

The version of this file that you are currently reading is:

$Id$

If there are more recent versions of this file, you can find a list of
those changes at:

L<http:E<sol>E<sol>slashcode.cvs.sourceforge.netE<sol>slashcodeE<sol>slashE<sol>INSTALL>


=head1 INSTALLATION

=head2 Installation Note

All of the installation steps below should be executed as root.  If this
is a problem, then Slash is probably not for you (see "Non-Root" below,
under "INSTALLATION OPTIONS").  Type carefully.  Now's a good time to
back up anything important.


=head2 Installation Procedure

There are eight steps to installation.  Anything already done can be
skipped -- but only if you have the correct version and configuration,
particularly with Apache/mod_perl.

=over 4

=item 1.

B<Install MySQL.>

If it is already installed, doublecheck that its version is at least the
minimum required (see L<"REQUIREMENTS">).  If you have questions about
the installation process, please refer to MySQL documentation.

Slash requires that your MySQL server run in the GMT timezome.  Find your
global my.cnf file (probably C</etc/my.cnf> or C</etc/mysql/my.cnf>),
locate the C<[mysqld_safe]> (or C<[safe_mysqld]>) group, and add this line
to it:

	timezone = GMT

Start MySQL (it must be running for the installation of Slash and some
perl modules).  Or, if it is already running, restart MySQL (if you have
other services using MySQL, you should probably stop and start them --
make sure they are timezone-agnostic!).

Create a database to be used by Slash.  Our default name is 'slash':

	CREATE DATABASE slash;

Create a username/password that can access that database, and ensure
that user has at least privileges to select, insert, update, delete,
lock, create, drop, index and alter.  For example, if your whole site
(slashd daemon and apache) will run on the same machine as your mysql
server, and you wanted to use the mysql username 'slash', you might:

	GRANT SELECT, INSERT, UPDATE, DELETE, LOCK TABLES, CREATE, DROP,
	INDEX, ALTER ON slash.* TO 'slash'@'localhost'
	IDENTIFIED BY (quoted password);

	GRANT PROCESS ON *.* TO 'slash'@'localhost' IDENTIFIED BY
	(quoted password);

In this case, 'slash' would also be the name of your MySQL user as
described in L<"Types of Users"> below.  You'll have to give your MySQL
user to DBIx::Password when you install and configure it, so don't
forget it.

=item 2.

B<Install perl.>

Perl is likely already installed on your machine; doublecheck that its
version is at least the minimum required (see L<"REQUIREMENTS">).

Also, check the "Libraries" (or "Debian libraries") section under
L<"REQUIREMENTS">, below.  You may need to install dev packages for not
only perl but mysql and expat as well and now's a good time to take care
of that.

=item 3.

B<Install Apache and mod_perl.>

B<You MUST install mod_perl and Apache as directed here>.  OK, that is
not strictly true, but unless you really know what you're doing,
just assume it's true. If you already have mod_perl installed,
it is probably not configured properly to work with Slash and
you will have to rebuild it.

If you are using the provided httpd.conf file from the slash
distribution, and find that Apache is giving you errors, chances
are mod_perl is not installed correctly, and you need to build
it from scratch. Not following this direction is one of the most
common reasons we see for a Slash install not working.

Of course, if you have your own Apache modules or build options,
you will need to modify the instructions here appropriately.

First, untar apache and mod_perl.  Then, go to the mod_perl directory,
and have mod_perl build and install apache for you:

	perl Makefile.PL APACHE_SRC=../where_you_have_apache/src \
		DO_HTTPD=1 USE_APACI=1 PERL_MARK_WHERE=1 EVERYTHING=1 \
		APACHE_PREFIX=/where_apache_will_be_installed
	make
	make test
	make install

B<NOTE>: You may be unsuccessful with C<make test> if the perl modules
are not yet installed. However, some perl modules will not install
without Apache and mod_perl installed. If you wish, skip C<make test>,
run C<make install>, install the perl modules in step 4, and then come
back and run C<make test> here again to make sure everything is OK.

B<NOTE>: If you know what you're doing, Slash will work with a DSO
Apache. Be sure you're on the latest versions of Apache and
mod_perl and remember PERL_MARK_WHERE=1 and EVERYTHING=1.

B<NOTE>: See also "Other requirements" under L<"REQUIREMENTS">.

B<Ubuntu NOTE>: In mid-2006 Ubuntu 6.x switched sh to point to dash
instead of bash, which apparently breaks the above step (because dash's
'echo -E' isn't compliant enough for apache's 'configure'). We're looking
into it, but for now apparently (temporarily) linking /bin/sh to /bin/bash
during this step is a workaround.
L<https:E<sol>E<sol>launchpad.netE<sol>ubuntuE<sol>+spec/dash-as-bin-sh>
(Update: this appears to no longer be a problem, but if you encounter
problems on Ubuntu, check where your /bin/sh points.)

=item 4.

B<Install the perl modules.>

Slash is powerful and complex, and, rather than reinvent the wheel, it
often relies on CPAN modules.  Open-source code reuse has many advantages.
One disadvantage is that installing all those modules can be tricky,
as you may be about to find out.

You could install each module in F<Bundle/Slash.pm> by hand, but this
would be time-consuming.  Instead, you'll want to install the bundle
C<Bundle::Slash> using CPAN.

=over 4

B<IMPORTANT NOTES (read through these first! really!)>:

=over 4

=item B<Overall comment about CPAN module failure>

It is possible that upon typing "install Bundle::Slash", you will have
one or more modules fail to install on the first try.  The rest of the
modules will be successfully installed but some won't.  In that case
you will want to fix the problems and retype "install Bundle::Slash"
to make sure everything proceeds smoothly.  Once that command gives you
just a long list of "Foo::Bar is up to date," you are done.  Until that
point, you are not done;  you must resolve the errors.

=item B<Old Version of Bundle::Slash>

If you have previously installed Bundle::Slash, you will want
to install it again, but you will need to delete the existing
version.  Go to your F<.cpan/Bundle> directory (usually
F<~/.cpan/Bundle/>) and remove F<Slash.pm>.

=item B<Overactive CPAN>

With some versions of the CPAN module, the module will try to
download and install the latest version of perl.  Watch what
the module is doing; if it begins to download an entire perl
distribution, interrupt it (hit ctrl-C) until it stops, then try
again with the CPAN module.  This should not be an issue in the latest
version of Bundle::Slash.

=item B<Uninstalling Old Modules>

Sometimes, you will be installing a newer version of a module that exists
elsewhere on the system.  You probably want to tell the CPAN module to
automatically remove older files.  To do that from the CPAN shell, type:

	cpan> o conf make_install_arg UNINST=1

And if you want that to be CPAN's default from now on, add:

	cpan> o conf commit

=item B<Automatically Installing Dependencies>

Some of the modules in Bundle::Slash require other modules.  We have
not put some of those other modules in Bundle::Slash because, if those
requirements change in the future, we don't want to make future Slash
sites install more than they have to.

If you see this:

	---- Unsatisfied dependencies detected during [FOO/Bar-1.23.tar.gz] -----
	    Foobar::Baz
	Shall I follow them and prepend them to the queue
	of modules we are processing right now? [yes] 

That's normal;  just hit return.

If it annoys you to have to do this, edit the C<prerequisites_policy>
field of your CPAN/Config.pm file.  Or, just do this to change it to
automatically follow dependencies and commit the change:

	cpan> o conf prerequisites_policy follow
	cpan> o conf commit

=item B<Data::JavaScript::Anon>

There are bugs in versions earlier than 1.00 that break our JS.  Unfortunately,
CPAN seems to prefer version 0.9 even though 1.00 is available.  You may
have to install a better version in CPAN by hand:

  cpan> install A/AD/ADAMK/Data-JavaScript-Anon-1.00.tar.gz

=item B<Additional Libraries>

You must have certain libraries existing on your system before building,
for Compress::Zlib, XML::Parser, DBI and DBD::mysql.  See "Libraries"
under L<"REQUIREMENTS">, below.

=item B<BSD Systems>

If running BSD, also install the BSD::Resource module.  We have heard
reports of minor problems running Slash on BSD, but you are welcome
to try.  See SLASH_PREFIX below, and after the install, doublecheck
the init scripts.  If you have to make changes to get it to work, send
us patches or detailed bug reports please: we want to support the BSDs.

=item B<DBIx::Password>

When installing DBIx::Password, you will be asked for various
information, the same information used to create the database
and database user in Step 1.  First, you'll be asked for a
B<virtual user> name, which will be the identifier for all of
this data.  You can just use the name of your site,
or any other alphanumeric string.  This string will be your
"DBIx::Password virtual user" as described in L<"Types of Users"> below --
you will use this in other places, so don't forget it.

Then you'll be asked for your DBI driver (mysql), the name of the database
you CREATEd in Step 1, its machine (maybe 'localhost' or an IP number) and
port, and then the MySQL user name you GRANTed privileges to in Step 1
and its password.

Some perl modules you can hit return for defaults and they'll work.
This isn't one of them. If you don't understand what you're doing here,
don't fake it -- that's a common reason for Slash installations failing.

=item B<Documentation>

To read the README for any module, before or after installing:

	cpan> readme MODULE

To read the documentation of any of the modules, once they have been
installed, type C<perldoc MODULE> at the command line.

See L<perlmodinstall> for more information on installing perl modules.

=back

=back

Now that you have read the above notes, you're ready to install the
perl modules.

To use the CPAN module, invoke the CPAN shell:

	perl -MCPAN -e shell

(Or, you may have the program "cpan" already available, which
does the same thing.)

If this is the first time you've invoked CPAN, you will be asked to
configure it.  Note that CPAN works best if most or all of these helper
programs are installed:  bzip2 gzip tar unzip make curl lynx wget ncftpget
ncftp ftp gpg.  If your OS installation is very anemic and you lack most
of them, you might ^C its questions, install the missing programs, and
then re-invoke the CPAN shell to restart configuration.

It's probably a good idea here to install the latest version of the CPAN
module itself, along with all the helper modules it requires.  This is
an optional step but may make the rest of module installation easier:

	cpan> install Bundle::CPAN

If you chose to do that, then afterwards, C<exit> the CPAN and reinvoke it.
(The plain shell command "cpan" will probably now work.)

Next, install some important networking modules.  This is also optional
but, if there are problems with these modules, you'll want to resolve
them before moving on to the rest of the installation:

	cpan> install Bundle::LWP

Make sure all those modules are installed and up to date before
proceeding.  Note that Net::Cmd has a history of being a little broken
in its tests;  if it fails on tests 8 and 9 of t/require, then it's OK;
just do C<force install Net::Cmd> and repeat C<install Bundle::LWP>.
On Mac OS X and possibly other operating systems, if LWP's live/https
tests fail, C<install Net::SSL> manually and retry.

Assuming you chose to install the LWP, then after it's been configured
successfully, again, C<exit> the CPAN and reinvoke it.

Finally, you must install Bundle::Slash:

	cpan> install Bundle::Slash

This will be a long process.  Several modules will ask to be configured
during this process.  Here are some tips:

=over 4

=item B<DBI>

Don't worry about the threading warning.  Slash doesn't use threads.

=item B<DBIx::Password>

See "DBIx::Password" under IMPORTANT NOTES above.

=item B<Apache::Test> and B<Apache::Cookie>

You will need C<httpd> and C<apxs> in your $PATH, and even if they
are there, you will probably see the lengthy error that starts "Apache
cannot spawn child processes as 'root'".  This is because, ironically,
Apache::Test's self-tests are a colossal pain to actually run (I take
the option to skip them).  And personally I just C<force install
Apache::Cookie> which is lame but solves the problem.

=item B<Template>

The Template Toolkit is a complex install.  Try accepting all the
defaults and see if it works.  It has 90 test scripts with over 2000
tests, and installation will be halted if just 1 of these tests fails.
Do a C<look Template> and try your best to resolve the issues.
The F<README> includes a URL to the mailing list archives, where you
may find help.  If you're getting 100 errors, you need to fix them,
but if you're down to 1 or 2 you can't fix, you might just make a note
of what the failures were and just C<force install Template>.

=item B<Other failures>

We can't predict whether bugs will appear in CPAN modules in future.
Often the bugs are not in the software proper, but in its too-strictly
coded test suites, which don't allow for changed but still-legitimate
output.  When this happens, the module itself is fine but it will not
install unless forced.  As of October 2006, we've noticed the following
module throw spurious errors, requiring a C<force install>:

	HTML::CalendarMonth 1.18

=back

If you have problems, feel free to re-run C<install Bundle::Slash>.  It
will safely skip anything already installed.

Again:  once you are able to do C<install Bundle::Slash> and see nothing
but a long list of modules that are "up to date," you are done.  Until you
see that, you are not done with this step!

If you wish to take full advantage of Slash, there are some plugins
not installed and vars not turned on by default, which provide
additional features, improve performance, or help in testing, which
require additional perl modules and sometimes non-perl libraries.
See the listing at the bottom of Bundle/Slash.pm, and see also the
tips in plugins/Admin/README, plugins/HumanConf/INSTALL-NOTES, and
plugins/Stats/README.

=item 5.

B<Install Slash.>

Unpack the distribution, go to the new directory that
creates, and type:

	make
	make install

B<Note>: you will want the GNU versions of fileutils and make.  Older
versions of install, and make and cp from other systems, might not work.

There are a few options to C<make> and C<make install> you may
want to change.

	option		default			purpose
	==========================================================
	SLASH_PREFIX	/usr/local/slash	Location for
						installed files
	INIT		/etc or /etc/rc.d	Location for init
						scripts
	USER		nobody			User to own files
	GROUP		nobody			Group to own files
	CP		cp			Name of or path to
						alternate 'cp'
	INSTALL		install			Name of or path to
						alternate 'install'

(USER and GROUP can also be changed later on a per-site basis,
in step 6, while running C<install-slashsite>.)

So, for example, you might type (although the default SLASH_PREFIX
is I<strongly> recommended):

	make SLASH_PREFIX=/home/slash
	make install SLASH_PREFIX=/home/slash

When done, a configuration file for Apache will be created at
F<$SLASH_PREFIX/httpd/slash.conf>.  You can put its contents into your
httpd.conf, or you can just C<Include> it in your httpd.conf.  You
must do one or the other!

B<WARNING!>

Please be aware that if you include F<$SLASH_PREFIX/slash.conf>
or F<$SLASH_PREFIX/sites/sitename/sitename.conf> more than once,
or if this file shares contents with directives in httpd.conf,
that your Slash site WILL break. The directives in
F<$SLASH_PREFIX/slash.conf> should be run only ONCE in any any
site context.  Read through F<$SLASH_PREFIX/slash.conf> to make
sure it all looks proper.

=item 6.

B<Install your Slash site.>

At this point, you may want to (re)read L<"DBIx::Password"> in L<"SECURITY
NOTES"> at the end of this section, and consider the option of installing
your site with a custom unix system user and group for added security.
You will be prompted for user and group shortly.

Go to your installation directory (by default, F</usr/local/slash>)
and execute (where C<VIRTUAL_USER> is the name of the virtual
user given in the DBIx::Password distribution):

	bin/install-slashsite -u VIRTUAL_USER

The program will prompt for answers to several configuration questions.
Then it will install your site.

Another configuration file will be created at
F<$SLASH_PREFIX/$SITENAME/$SITENAME.conf>, which will be C<Include>'d
in F<$SLASH_PREFIX/httpd/slash.conf>.  You'll want to add an C<Include>
for the latter in your Apache's F<httpd.conf> if you haven't done so on
a previous site install.

If you are using virtual hosting by hostname, you may also need to add
a NameVirtualHost.

If you don't have your Slash site in the root of the web server
(e.g., L<http:E<sol>E<sol>www.example.comE<sol>mysiteE<sol>> instead
of the more usual L<http:E<sol>E<sol>www.example.comE<sol>>), you
will need to adjust the rootdir, rdfimage, imagedir, absolutedir,
and cookiepath variables, and you also need to change your Apache
config appropriately.  If you're planning on having sections with
more than two dots in the hostname (e.g. your mainpage will be at
L<http:E<sol>E<sol>division.company.comE<sol>> with a section at
L<http:E<sol>E<sol>newprojects.division.company.comE<sol>>) you will
also want to set the cookiedomain var (e.g. to .division.company.com).
These are all in the vars table of your database.

B<NOTE>: Read the message printed at the end of running install_slashsite.
Failure to pay attention here is another common reason we see for Slash
installations not working.

B<Ubuntu NOTE>: Reported after installing on Kubuntu 7.10, a Slash install's
idea of run-levels was not sufficient to start slashd at boot.  The following
makes sure that all the right run-levels are covered, and that rebuilding
Slash won't mistakenly double-start the daemon:

  sudo update-rc.d -f slash remove
  sudo update-rc.d slash defaults
  sudo mv /etc/rc3.d/S*slash /etc/rc3.d/S99slash
  sudo mv /etc/rc6.d/K*slash /etc/rc6.d/K99slash

=item 7.

B<Start it up.>

After installation of the site is done, you'll need to start Apache.
Stop it if necessary, then start it:

	apachectl stop
	apachectl start

Use the apachectl script under the APACHE_PREFIX you specified in step 3.
Don't try its "restart" or "graceful" options, you'll need to do a full
stop and start.

Then run slashd.  This should be done via the init script:

	/etc/init.d/slash start

slashd is the daemon that runs routine maintenance on Slash sites,
including sending out daily mailings, cleaning up the database,
and updating stories.  The init script above will start up an
individual slashd daemon process for each installed site (and while
running, they will spawn child processes, some of which may run for a
long time or until you stop slashd with "slash stop").

Now's a good time to (re)read the L<"SECURITY NOTES"> section at the
end of this file.

=item 8.

B<Stay in touch.>

For as long as you are running a Slash site, you should stay on our
"slashcode-announce" mailing list, to receive notification of security
issues (and, rarely, other major news of interest to Slash admins).
You can sign up at:

	https://lists.sourceforge.net/lists/listinfo/slashcode-announce

You may wish to subscribe to "slashcode-general", for discussion of
running Slash sites.  This list probably averages 1-2 emails a day,
mostly on administration issues, and bugs and features in Slash.

	https://lists.sourceforge.net/lists/listinfo/slashcode-general

You may also wish to create a user on slashcode.com and subscribe to
its daily newsletter.  If/when news is posted to that site, you'll be
in the loop.

If you want to register your new site, feel free to do so at
L<http:E<sol>E<sol>slashcode.comE<sol>sites.pl>.

=back


=head1 INSTALLATION OPTIONS

=head2 Multiple Servers

You can, of course, have a separate database server from your Slash
server.  Further, you can have multiple web servers for one Slash site,
and a good thing too because web server RAM/CPU will probably be your
first bottleneck as your site grows.

Slashdot has one primary server with all of the code (Apache, perl,
etc.) in /usr/local.  That server runs slashd and NFS.  Our slashd writes
directly to its /usr/local/slash.  Each web server mounts /usr/local
read-only over NFS.  (Yes, NFS has a reputation for being flaky, but
we've never had a problem with it, which we attribute both to good
sysadmins and to only exporting our filesystem read-only.)

Some notes:

=over 4

=item *

Make sure the MySQL server allows the user to log in from each web
server, and the slashd server.

=item *

Make sure, if you use the same httpd tree on all machines, that
the httpd.conf is listening to the proper IP addresses.  This can be
done by putting all of the IP addresses in the conf file, or by having
a separate Listen file on each machine.  Similarly, make sure that
each web server's logfiles are unique to each machine, not written to the
NFS volume.

=back


=head2 Virtual Hosts

Slash has support for virtual hosts, so you can have multiple
Slash sites on one machine.  Simply execute step 6 in the install
process for each Slash site (after adding a new virtual user to
DBIx::Password for each).


=head2 SSL

In Slash, there are two variables for the root URL of the site.
B<absolutedir> is the full URL, including protocol, while B<rootdir>
is the URL without protocol:

	absolutedir	http://slashcode.com
	rootdir		//slashcode.com

B<absolutedir> is used only for creating external links to the site
(such as in RSS files).  B<rootdir> is used for internal links; that
way, you can use the same HTML pages for SSL and non-SSL.  You don't
have to do anything special to the code or preferences to allow it to
work with SSL by itself, SSL and non-SSL together, or non-SSL by itself.


=head2 Non-Root

It is theoretically possible to install and run everything here without
root.

It is not easy.  If you don't know your flavor of unix intimately, we
don't recommend trying this.

Describing the process for a non-root install would take up significant
space and time, having to account for differences in various systems,
and all the workarounds necessary for it to work.  We don't support it,
and we're not going to document it.

If you must have a non-root install, consult the various documentation
for Apache, MySQL, and perl about running and installing without root
access.  Then, for Slash, you need to set the make variables PREFIX,
SLASH_PREFIX, and INIT appropriately for your needs.

B<Note>: Slash sites (or, more accurately, Apache + mod_perl and MySQL) take
up a lot of system resources.  It is I<not advisable> for anyone to
run Slash on any system, without the permission of the administrator
of that system.


=head2 Memcached

Memcached is not required, but Slash includes optimizations that move
load from your (expensive) MySQL server to a (very cheap) memcached
server or servers.  If you are concerned about performance, this is one
of the first options to install.  You can probably install it
using your operating system's package management, and/or see
L<http:E<sol>E<sol>www.danga.comE<sol>memcachedE<sol>>.

A 64 or 128 MB memcached instance should be plenty for moderate-sized
Slash sites.  Just set the vars 'memcached', 'memcached_keyprefix', and
'memcached_servers', and restart apache and slashd.  That's it.

(As of August 2006, Slashdot uses a total of 2 GB of memcached, but
that's in small allocations spread across many servers because we like
redundancy.  Last I checked the 2 GB wasn't even half full.)


=head2 Separate Image Server

Those of you with infinite RAM will have no problems hosting as many Slash
sites as you want on a single box running just Apache.  Those whose RAM
is limited may be able to keep your MaxClients down to a reasonable level
to avoid going into swap, and still not lock clients out of your website,
by using a separate webserver process to deliver your images.

This is possible with any website, of course, not just a Slash site, but
because Slash's httpd clients all have mod_perl, a lot of perl modules,
and a lot of templates all compiled into RAM, they are especially heavy.
While serving an image may take only a few milliseconds, which would you
rather have tied up on your computer for those milliseconds, 25 MB of RAM
or 5 MB?

Slashdot, and some other Slash sites we're hosting, are currently using
boa 0.94.14rc17 (L<http:E<sol>E<sol>www.boa.orgE<sol>>) for images.
Boa is fast and has a small footprint.  It's easy to build
(C<./configure && make>) but you have to install it yourself by
copying the binary and mkdir'ing a little tree wherever you want it.
We did roughly this.  Your mileage may vary.  This sets up an alternate
server just for images on port 8080, and sets Slash's imagedir var to
point to it.  Your apache will still serve images at the old URLs if
anyone requests them, but nobody will, because your site's pages will
all point to boa:

	# Install boa and set up its files.
	cd /usr/local/src/boa-0.94.14rc17
	./configure && make
	mkdir /usr/local/boa
	mkdir /usr/local/boa/bin
	mkdir /usr/local/boa/htdocs
	cp -a src/{boa,boa_indexer,webindex.pl} /usr/local/boa/bin/
	ln -s /usr/local/slash/site/mysite/htdocs/images /usr/local/boa/htdocs/images.mysite.com
	touch /usr/local/boa/htdocs/favicon.ico

	# Set up and edit boa conf file.
	cp examples/boa.conf /usr/local/boa/
	# At this point we patched /usr/local/boa/boa.conf, changing
	# Port to 8080, ServerName to www.mysite.com, DocumentRoot to
	# /usr/local/boa/htdocs, and commenting out the DirectoryIndex,
	# DirectoryMaker, Alias and ScriptAlias directives.

	# Start boa.
	/usr/local/boa/bin/boa

	# In mysql client:
	# UPDATE vars SET value='//www.mysite.com:8080/images.mysite.com' WHERE name='imagedir';
	# INSERT IGNORE INTO story_dirty SELECT stoid FROM stories WHERE in_trash='no';

	# Restart apache, slashd;  let slashd rewrite .shtml files both
	# recent and archived.

You'll probably also want to create a script in your init.d and rcN.d
directories so boa runs at startup along with apache.


=head1 UPGRADING

B<Some of these upgrade procedures are still in testing.  Please read
them entirely before beginning.  We are not responsible for any loss of
data or functionality.>

=head2 Slash 1.0 -E<gt> Slash 2.2

You've got a site running Slash 1.0, from 2001? We're so sorry to
hear that.

Please read the complete documentation of F<utils/slash1toslash2.2>.
We believe it will convert your database from Slash 1.0 to a new Slash
2.2 database, but it hasn't been tested in some time.  The program
documentation (which can be read with F<perldoc>) details exactly what
process it follows to do the conversion, so you can attempt to do it by
hand if you prefer.

=head2 Slash 2.0 -> Slash 2.2

Slash 2.2 is a major upgrade from Slash 2.0.  It takes a little bit
of work to get it going.

=over 4

=item 1.

BACK EVERYTHING UP ON THE EXISTING SITE.

=item 2.

Install Bundle::Slash.  If you have done so previously, follow
the instructions for removing the existing version of
Bundle::Slash before proceeding.

=item 3.

Apply this patch to your installed Slash::Install module (probably
easiest to hand-edit the file):

  --- Install.pm~ Wed May  9 15:02:34 2001
  +++ Install.pm  Fri Sep 28 12:44:41 2001
  @@ -116,7 +116,7 @@
   sub writeTemplateFile {
          my($self, $filename, $template) = @_;
          open(FILE, '>' . $filename) or die "$! unable to open file $filename to write to";
  -       for (keys %$template) {
  +       for (qw(section description title page lang name template seclev)) {
                  next if ($_ eq 'tpid');
                  print FILE "__${_}__\n";
                  $template->{$_} =~ s/\015\012/\n/g;

=item 4.

Run C<template-check> on your site, and make a note of every change
you've made to the standard templates.  You will need to make those
changes again, manually, later.

This is unfortunately unavoidable, because templates include code
that changes significantly between releases.  It is recommended
that you compile your changes into a THEME so they may easily be
updated and applied.

=item 5.

Stop Apache and slashd on the target machine(s).

=item 6

Install Slash.

B<If installing on a different machine ...>

=over 4

=item 1

Install slash 2.2 as normal.  Do not yet run C<install-slashsite>.

=item 2

Make sure that from this machine, you can access not only the database
used for this installation, but the one used for the old installation.
You may wish to, instead of accessing that database directly if it
on another machine, dumping it and adding it to your new database server
under a different name.

=item 3

Add a virtual user to DBIx::Password for the old installation.

=back


B<If installing on the same machine ...>

=over 4

=item 1

Create a new database for the new installation.  You cannot
use the same database for both installations.

=item 2

Add a new virtual user to DBIx::Password for the new database,
and update (and flush) MySQL privileges appropriately.  You cannot
use the same virtual user for both installations.

=item 3

It is highly recommended that you move F</usr/local/slash>
(or whatever your installation directory is) to a new location,
such as F</usr/local/slash-old>, and install a clean slash 2.2
installation.  However, this is not necessary to do; you may install
slash 2.2 on top of the slash 2.0 installation.

The reason to not move anything is that you can keep any customizations
done (images, additional scripts and plugins, static files, etc.).
The reason to move it is so that everything is clean.  It is highly
recommended that you move it, and then manually copy back the pieces
you want.

=item 4

In any event, either move the old directory, or don't, and
then install slash 2.2 as normal.  Do not yet run C<install-slashsite>.

=back


=item 7.

If you have plugins or themes from the old installation to install,
copy them over now.  Warning: some plugins and themes might need to be
ported first.  You may wish to deal with them later if they are not
yet ported to slash 2.2.

=item 8.

Run C<install-slashsite>.  Use the new virtual user.

=item 9.

Copy over any files (images, FAQs, etc.) that need to be copied, if necessary.

=item 10.

Run update script, F<utils/slash2toslash2.2>.  B<Read its instructions!>

=item 11.

Update templates.

=item 12.

Doublecheck Apache configs (httpd/slash.conf, site/sitename/sitename.conf).
These configs have changed from the last version.  Read the comments and set
them up as desired.

=item 13.

Start Apache.

=item 14.

Start slashd.

=back


=head2 Slash 2.2.x -> Slash 2.2.y

Read all of this section before doing any of it.

The first thing to do is to, as per the instructions below under
INSTALLATION, unpack the latest distribution and run make and make
install with the proper arguments.

=over 4

=item Overwriting Changes

This process will overwrite any customizations of your installed
modules, or customizations of the installed scripts in
/usr/local/slash/themes/ and /usr/local/slash/plugins/ (for themes
and plugins that come with Slash).  If you ran C<install-slashsite>
with the default option of using symlinks, and made customizations
to the originals instead of breaking the symlink and copying the file
over, then this will overwrite your changes.

If you did modify the original instead of a copy, then break the
symlink, copy over the original (as modified), and then continue.
The original will be copied over by the new version, and your modified
copy will remain intact.

=item Templates

With every update, there are changes to templates.  But most people
will modify their templates.  A relatively simple way to see what
has changed is to use template-tool and template-check.  This
procedure should help most users deal with the integration of new
templates into an existing site (it will only work with the slashcode
theme, but a simple modification to the code of template-check
can fix that).

=over 4

=item Dump

Use template-tool to dump your templates into an empty directory.

	% mkdir templates
	% cd templates
	% template-tool -u VIRTUAL_USER -d

(Defaults to current directory.)

=item Compare

Use template-check to compare installed templates in
/usr/local/slash/themes/slashcode/ and /usr/local/slash/plugins/ against
the templates that have been dumped.

	% template-check -u VIRTUAL_USER

(Defaults to current directory.)

This will use diff to show you the differences.  You can either go
into the templates with a text editor (in another window) and change
the dumped ones by hand, edit them by hand in the Template Editor
via the web browser, or take a note of every template you want to
copy over your existing template.

After each directory of templates is done, hit "q" to continue to
the next plugin/theme.

=item Sync

If you made changes by hand via the web, you are done.  Otherwise, take
the list of templates to update, and pass the full filenames to
template-tool (this will either be the templates you modified by hand
in the dump directory, or the unmodified ones in the installation
directories). You might need to put each filename in quotes because of
the ";" character in the filenames.  This will overwrite your existing
template with the new template.

	% template-tool -u VIRTUAL_USER -s LIST

=back

=back

=head2 Slash 2.2.6 -E<gt> Slash CVS

Use the sql/mysql/upgrades file;  see L<"VERSIONS">, "CVS tags", below.
This file is human-readable and very long. You can upgrade a 2.2.6 to
the latest CVS by methodically applying every step in this file, but
it is tedious and requires an engaged human brain reading the comments
(i.e., don't "mysql slash < upgrades", that will fail miserably).

=head2 Slash CVS -E<gt> later Slash CVS

Again, use the sql/mysql/upgrades file (and the caveat just mentioned
still applies).  Start from the CVS tag you left off at, and proceed
to the CVS tag you upgraded to (which should be the end of the file).
If you're not sure which tag you left off at, you might check the var
'cvs_tag_currentcode', which will contain the right value if you last
updated after September 2005.

In general, you should stop apache and slashd, do a "make install",
apply the upgrades file a line at a time for each Slash site, run
"template-tool -U -u virtusename" and "symlink-tool -U -u virtusername"
for each Slash site, and then start slashd and apache back up.


=head1 REQUIREMENTS

=head2 Software Requirements

Below, we list the main software components needed.  The recommended
version is given.  Usually this is the version we have done extensive
testing on, typically a version we have used on Slashdot for some time.
In parentheses we include (but do not recommend or support) the earliest
version we believe could work.

=over 4

=item Perl

Version 5.8.7 (5.6.1).

	http://www.cpan.org/

=item MySQL

Version 5.0.22 (4.0.12).

	http://www.mysql.com/

MySQL 3.23.x is no longer supported, as of CVS tag T_2_5_0_33
(October 18, 2004).  MySQL 4.0.x is not being actively updated by
MySQL AB except for security issues (though as far as we know it still
works fine), so we would recommend that you upgrade to at least 4.1.x.
At some point in the future we will switch over to some syntaxes which
have been recommended for some time which will break on 4.0.x, so you'll
have to upgrade to at least 4.1.x eventually anyway.  (You probably have
until 2007 before we spring this on you.)

Slashdot ran on 4.1.x for a long time with no problems, so we now
recommend either that or 5.0.x.  We have been testing on 5.0.x for months,
and as of this writing (August 2006), Slashdot has been running on 5.0.18
and 5.0.22 for some time with no problems.  For what it's worth, we have
found the MySQL upgrade process, even between major versions, to be about
as painless as we could have imagined.

=item Apache

Version 1.3.34 (1.3.33).

	http://httpd.apache.org/

Since most of Apache 1.3.x's recent releases included security fixes,
we wouldn't recommend running an earlier version.  Slash is not compatible
with Apache 2.x and we have no plans to port to 2.x (though we aren't
excluding the possibility).

=item mod_perl

Version 1.29.

	http://perl.apache.org/

=item memcached

Version 1.1.12 (1.1.11).

See "Memcached" above.

=item Sendmail or other mail transport agent

Refer to your OS distribution.

=item Perl module distributions

The latest version of each perl module is recommended.  To download and
install them, use CPAN -- see L<"INSTALLATION">, item 4, "Install the
perl modules."

=item Libraries

For Compress::Zlib, the zlib development library is required.  For
XML::Parser, the expat library is required.  If they are not present
on the system already, download and install them before installing
the modules.

	http://www.gzip.org/zlib/
	http://sf.net/projects/expat/

The current list of required perl modules can be found in the
F<Bundle/Slash.pm> file.  At its end we also list optional modules,
which may be required depending on your setup.

=item Debian libraries

On Debian Linux, or Debian-based distributions like Ubuntu, the above
libraries can be installed with:

	apt-get install zlib1g zlib1g-dev libexpat1 libexpat1-dev

Also on Debian, as of the current writing (July 2006), you will want
libperl-dev.  DBD::mysql requires mysql_config and mysql.h;  on Debian
stable, try libmysqlclient12 (and -dev) for 4.0.x and/or libmysqlclient14
(and -dev) for 4.1.x.  On testing or unstable, try libmysqlclient15off
and libmysqlclient15-dev.

=back


=head2 Hardware Requirements

There are no specific hardware requirements.

Slash is designed to work well on multi-machine setups, with one or
more webheads that are separate from one or more MySQL DB machines.
But for low-load sites (1-5 pages/sec or slower), it can probably be
run OK on a single machine.

Apache (with mod_perl) and MySQL both take up a lot of RAM. Running a
complete system with 128MB might be possible, if you do some tuning of
the configuration, but a practical minimum of 256MB is recommended, and
you will be much happier with at least 1GB of RAM.  See L<"INSTALLATION
OPTIONS">, "Separate Image Server" for tips on saving some RAM.

Disk space depends on how busy you expect the site to be.  Slash keeps
a small database -- even Slashdot's DB compresses down to a few GB.
The disk files as installed are under 0.5 GB, and grow predictably as
stories and comments are added (keep an eye on the F<site/foo/logs/>
directory, too).  A minimum of 1 GB of disk is recommended.

Necessary processor speed is also dependent on how busy the site is.
A Pentium II/400 equivalent is recommended, but obviously, the faster
the better.

For the curious, Slashdot (as of September 2001) runs on nine machines:
nine webservers (each is Pentium III/600, 1GB RAM, 9GB hard drive), one
NFS server (600MHz PIII, 1GB RAM), and three database servers
(quad 600MHz PIII, 4GB RAM).  One database server is
live, one is a replicated backup, and a third is for doing live searches
and performance-intensive SELECTs by daemons etc.

However, this is certainly overkill for most sites (and possibly even
overkill for Slashdot).  slashcode.com runs on two web servers and one
NFS/database server.  Many sites can run fine on just one machine for
everything (we use a minimum of two web server machines on every site
for load balancing and redundancy).

If you're concerned about performance, the F<bin/mechmonkey> script
may help provide load vaguely similar to real user patterns, though
it doesn't try simulating logged-in users.  One more data point:  my
personal machine is a 2.4 GHz Athlon with 1.5 GB RAM and an IDE disk,
and it easily handled the load when its Slash site got a mild Slashdotting
(a link in a non-major story, about 10 pages/sec).


=head1 VERSIONS

Each version of slash has a code name, and the files on CVS for that
version are tagged with that name.  The current release is always
MAIN.  The versioning scheme is as Linux and perl are,
revision.version.subversion.  version is even for releases, and odd
for development.  The codename applies to the development version
and subsequent release.

For example, 1.0.11 is a normal release, while 1.1.0 is the first
development release for what will be the next release (either 1.2
or 2.0).

The CVS repository is tagged with version numbers, so to get release
1.0.3, use tag "v1_0_3_0".  The last number (in this case a zero) will
be incremented during development ("v1_0_3_1", "v1_0_3_2", etc.) until
the next release.  Non-release versions are tagged with a T_ or R_
prefix.  We are currently developing 2.5.x, so our CVS tags are
T_2_5_0_x and R_2_5_0_x (though there was no 2.4.0 release and to date
has been no 2.5.0).

=head2 Codenames

=over 4

=item v1.0

beast

=item v2.0

bender

=item v2.2

fry

=item v2.3

(never released)

=item v2.4

(never released)

=item v2.5

leela

=back

=head2 Security note

We are no longer releasing bugfixes, even for security, for the 1.0
or 2.0 versions, and do not recommend their use.  If we become aware
of security issues in the 2.2 tree, we will release another version.
For this reason, if you are using any version of Slash in 2.2.x or
earlier, we recommend you upgrade at the very least to the latest version
of 2.2, which as of this writing (August 2006) is 2.2.6.

=head2 CVS tags

Our development of 2.3/2.5 has gone on exceptionally long without a
tarball release of either 2.3.0 or 2.5.0.  Most Slash hosting sites are
choosing to follow CVS instead of waiting, and we encourage this.

Installation of the latest CVS (as of August 2006) is almost identical
to the installation of 2.2.

You probably do not want to use the
very latest CVS, as the Slash developers are constantly updating it.
If you wish to live on the edge, try a T_2_5_0_x tag ("Testing in 2.5.0
branch" -- one or two of these are added every week, Slashdot uses them,
but they may have bugs).  If you are content with recent code that the
developers believe is likely to be free of major bugs, look for a recent
R_2_5_0_x cvs tag ("Release candidates for 2.5.0").

To upgrade from 2.2.x to the CVS tree, you will need to follow the
instructions in the sql/mysql/upgrades file.  At the moment, these are
just SQL commands you will need to issue, but read carefully because
you may have to use judgement and issue command-line commands and so on.
(We are working on a tool to automate this process.)  Once you are
upgraded to, or have installed, a given CVS tag, upgrading to later
CVS tags is simply a matter of following along in that file -- we append
as we go, and each T_* tag is clearly marked.

=head1 TROUBLESHOOTING COMMON INSTALLATION PROBLEMS

Here are some common errors reported by other site administrators.

=over 4

=item *

Webpages show the error: "The server encountered an internal error or
misconfiguration..."

Check your Apache error logs for a more specific error.

=item *

"Can't locate Slash.pm in @INC..."

One possibility is that you didn't actually C<make install> Slash
in step 5, which would be a pretty serious omission.

It's also possible that the apache or slashd process issuing this error
doesn't have permissions to read Slash.pm, or is using a different version
of perl than you expect with a different set of @INC directories than
you expect.  Try, at the command line:

	which perl
	head -1 /usr/local/slash/sbin/slashd
	perl -MSlash -le 'print $INC{"Slash.pm"}'

and see if it emits the perl binaries you expect and the location of
Slash.pm that you expect.  Check file permissions and see "Multiple perls
installed" below.

=item *

I installed Slash twice and it didn't work.

Did you uninstall before reinstalling?  See "UNINSTALLING" below.
If you intend to reinstall with the same database and site name,
steps 4 and 7 are not optional.

=item *

"Can't locate MIME/Types.pm in @INC..."

This used to be required only for plugins/Blob and you probably didn't
follow its README after you installed it.  Now it's in Bundle::Slash;  try
reinstalling Bundle::Slash (and see "Old Version of Bundle::Slash" above).

=item *

DBD::mysql will not install.

As of October 2006, its tests by default assume you have a running mysqld
on localhost, with a database named 'test', accessible to the user
'root' with no password.  If you don't have a database named 'test',
create one with C<CREATE DATABASE test;>.  If you don't run mysqld
on the same machine as you're installing the module, or if you have a
password for its 'root' user (good idea), almost all its tests will fail.
You can either override the failures with

	cpan> force install DBD::mysql

or (better) run proper tests by telling it the actual mysqld host, user,
and password to connect to, with

	cpan> look DBD::mysql
	# perl Makefile.PL --usage
	# perl Makefile.PL --testmycustomargs=foobar
	# make && make test && make install

=item *

"Can't call method '(whatever)' on an undefined value at..."

Slash can't connect to your database server.  (This manifests as the
variable $slashdb being undef.  Which method happens to emit this error
depends on which code path first tries to use $slashdb.)

To start troubleshooting this, see "Database authentication issues" below.

=item *

I created a new author but s/he doesn't show up in authors.pl and can't
post stories.

For performance reasons, Slash aggressively caches the list of which
users are authors.  After you mark a user as an author and boost their
seclev (maybe to 100) in users.pl, go back to the command line and run
the refresh_authors.pl task by hand:

	# /usr/local/slash/bin/runtask -u yourvirtuser refresh_authors

Then restart apache and slashd.  That user will now be able to post
stories.  The authors.pl listing will update some time after the first
story is actually posted.

=item *

Freshly-posted stories aren't showing up on the homepage.

Are you sure slashd is running?  If a story appears on /index.pl but not
/index.shtml, and it's more than a few minutes old, check the output of
'ps' for slashd, and check slashd.log for errors.

=item *

"Use of uninitialized value in..."

Just a harmless warning, ignore it.  It helps us find errors, but you
don't need to worry about it.

=back

Here are some other common reasons why Slash installations fail.

=over 4

=item *

Failure to build mod_perl with PERL_MARK_WHERE=1 EVERYTHING=1.

We emphasize this in the instructions for a reason. Go back and
reread the Installation Procedure, step 3.

=item *

Perl module installation troubles.

If you have a unix-like system with CPAN properly installed
and no serious firewall issues, perl module installation will
usually go pretty smoothly…