Here I describe the symlink approach to create a dokuwiki farm. This wiki was created using this approach.

• Quite simple
• Only the directories conf/ and data/ are copied, all other files are referenced through symlinks (only ~996K initial size per animal)
• You have to upgrade only one DokuWiki instance and all templates and plugins are available for all instances.
• Individual configuration per animal
• Virtual hosts supported
• Animals can be located in an arbitrary folder (in contrast to the other approach).

This is the only complete instance of DokuWiki.

• Run all commands in the following as root (under debian sudo -i).
• Adapt $farmpath.
• Adapt the link to the dokuwiki archive.

# path to the farm (ends without /):
farmpath=/var/www/dokuwiki-farm
cd `dirname $farmpath`
# adapt the link for an other version:
wget http://www.splitbrain.org/_media/projects/dokuwiki/dokuwiki-rc2010-10-07.tgz
tar -xzvf dokuwiki-*.tgz
# rename the folder from dokuwiki-YYYY-MM-DD to your farm folder name:
mv dokuwiki-*/ $farmpath
cd $farmpath
chown -R www-data:www-data data/ conf/
cat > inc/preload.php <<'EOF'
<?php
$dir = dirname($_SERVER['SCRIPT_FILENAME']);
if(is_dir($dir . '/conf'))
	define('DOKU_CONF', $dir . '/conf/');
else {
	$dir = preg_replace('#lib/(exe|plugin.*)#', 'conf/', $dir);
	if(is_dir($dir))
		define('DOKU_CONF', $dir);
}
?>
EOF
# the next step is only needed for the older dokuwiki-2009-12-25c!
cp lib/exe/indexer.php{,.orig}
patch lib/exe/indexer.php <<'EOF'
263,265c263,265
< 
<     if(@file_exists(DOKU_INC.$sitemap)){
<         if(!is_writable(DOKU_INC.$sitemap)) return false;
---
>     $sitemap_path=DOKU_CONF.'../';
>     if(@file_exists($sitemap_path.$sitemap)){
>         if(!is_writable($sitemap_path.$sitemap)) return false;
267c267
<         if(!is_writable(DOKU_INC)) return false;
---
>         if(!is_writable($sitemap_path)) return false;
270,271c270,271
<     if(@filesize(DOKU_INC.$sitemap) &&
<        @filemtime(DOKU_INC.$sitemap) > (time()-($conf['sitemap']*60*60*24))){
---
>     if(@filesize($sitemap_path.$sitemap) &&
>        @filemtime($sitemap_path.$sitemap) > (time()-($conf['sitemap']*60*60*24))){
303c303
<     io_saveFile(DOKU_INC.$sitemap,$data);
---
>     io_saveFile($sitemap_path.$sitemap,$data);
EOF

Now you can configure your dokuwiki-farm as you like. The configuration will be the template for the animal wikis.

With this patch, the plugins are disabled based on the existence of the file conf/plugin.{$pluginname}.disabled. Note, that all previously disabled plugins get enabled by application of the patch, since the former mechanism is ingored.

• Adapt $farmerpath (same as above).

cd $farmerpath/inc
cp -a plugincontroller.class.php plugincontroller.class.php.dist
patch -p0 plugincontroller.class.php <<'EOF'
--- plugincontroller.class.php.dist	2010-01-17 11:35:46.000000000 +0100
+++ plugincontroller.class.php	2010-04-01 14:08:21.000000000 +0200
@@ -104 +104 @@
-            return @unlink(DOKU_PLUGIN.$plugin.'/disabled');
+            return @unlink(DOKU_CONF.'plugin.'.$plugin.'.disabled');
@@ -111 +111 @@
-            return @touch(DOKU_PLUGIN.$plugin.'/disabled');
+            return @touch(DOKU_CONF.'plugin.'.$plugin.'.disabled');
@@ -125 +124,0 @@
-
@@ -130 +129 @@
-                }elseif(@file_exists(DOKU_PLUGIN.$plugin.'/disabled')){
+                }elseif(@file_exists(DOKU_CONF.'plugin.'.$plugin.'.disabled')){
EOF

• Adapt farmpath (same as above).
• Adapt animalpath.

create-animal.source

# path to the farm (ends without /):
farmpath=/var/www/dokuwiki-farm
# path to the animal, that should be created (ends without /):
animalpath=/var/www/animal1
mkdir -p $animalpath && cd $animalpath
cp -pr $farmpath/{data,conf} .
# www-data is the webserver user:
chown -R www-data:www-data data/ conf/
ln -s $farmpath/{index.php,doku.php,feed.php,inc,lib} .
cat >> conf/local.php <<'EOF'
\$conf['savedir'] = '$animalpath/data';
EOF

First, we enable URL rewriting with .htaccess file.

• Adapt $farmpath (same as above).
• Adapt $animalpath (same as above).
• Adapt $animalbasedir.

# This is what stands after the domain name http://animal1.example.org/wiki/ (ends without /):
animalbasedir=/wiki
# Turn RewriteEngine on, adapt RewriteBase and create the .htaccess file
sed 's@RewriteBase /dokuwiki@RewriteBase '$animalbasedir'@g' > $animalpath/.htaccess <<'EOF'
## You should disable Indexes and MultiViews either here or in the
## global config. Symlinks maybe needed for URL rewriting.
Options -Indexes -MultiViews +FollowSymLinks
 
## make sure nobody gets the htaccess files
<Files ~ "^[\._]ht">
    Order allow,deny
    Deny from all
    Satisfy All
</Files>
 
## Uncomment these rules if you want to have nice URLs using
## $conf['userewrite'] = 1 - not needed for rewrite mode 2
RewriteEngine on
#
## Not all installations will require the following line.  If you do, 
## change "/dokuwiki" to the path to your dokuwiki directory relative
## to your document root.
RewriteBase /dokuwiki
#
## If you enable DokuWikis XML-RPC interface, you should consider to
## restrict access to it over HTTPS only! Uncomment the following two
## rules if your server setup allows HTTPS.
#RewriteCond %{HTTPS} !=on
#RewriteRule ^lib/exe/xmlrpc.php$      https://%{SERVER_NAME}%{REQUEST_URI} [L,R=301]
#
RewriteRule ^_media/(.*)              lib/exe/fetch.php?media=$1  [QSA,L]
RewriteRule ^_detail/(.*)             lib/exe/detail.php?media=$1  [QSA,L]
RewriteRule ^_export/([^/]+)/(.*)     doku.php?do=export_$1&id=$2  [QSA,L]
RewriteRule ^$                        doku.php  [L]
RewriteCond %{REQUEST_FILENAME}       !-f
RewriteCond %{REQUEST_FILENAME}       !-d
RewriteRule (.*)                      doku.php?id=$1  [QSA,L]
RewriteRule ^index.php$               doku.php
EOF

Now we configure the virtual host for the animal.

• Adapt $animalpath (same as above).
• Adapt $animalhostname.

animalhostname=animal1.example.org
cd /etc/apache2/sites-available
tee $animalhostname <<'EOF'
<VirtualHost *:80>
    ServerName $animalhostname
    DocumentRoot $animalpath/
    <Directory $animalpath>
        Options FollowSymLinks
        AllowOverride All
    </Directory>
</VirtualHost>
EOF
ln -s $animalhostname ../sites-enabled/.
# reload config to enable the virtual host
/etc/init.d/apache2 reload

Enable config:userewrite and set config:basedir appropriately in the conf/local.php.

• Adapt $animalpath (same as above).
• Adapt $animalbasedir (same as above).

cd $animalpath
cat >> conf/local.php <<EOF
\$conf['basedir'] = '$animalbasedir/';
\$conf['userewrite'] = '1';
EOF